Initial commit (commit history cleanup)

.gitignore

@@ -0,0 +1,42 @@
+# playground
+[Bb]uild/
+[Pp]layground/
+
+# Prerequisites
+*.d
+
+# Compiled Object files
+*.slo
+*.lo
+*.o
+*.obj
+
+# Precompiled Headers
+*.gch
+*.pch
+
+# Compiled Dynamic libraries
+*.so
+*.dylib
+*.dll
+
+# Fortran module files
+*.mod
+*.smod
+
+# Compiled Static libraries
+*.lai
+*.la
+*.a
+*.lib
+
+# Executables
+*.exe
+*.out
+*.app
+
+# Birb2D Custom Files
+log.txt
+
+# Vim stuff
+.undodir

CMakeLists.txt

@@ -0,0 +1,39 @@
+cmake_minimum_required(VERSION 3.21.3)
+set(CMAKE_CXX_STANDARD 17)
+set(CMAKE_CXX_STANDARD_REQUIRED on)
+
+project(birb2d VERSION 0.1)
+
+set(ENGINE_SRC
+./src/font.cpp
+./src/math.cpp
+./src/audio.cpp
+./src/scene.cpp
+./src/utils.cpp
+./src/entity.cpp
+./src/events.cpp
+./src/logger.cpp
+./src/values.cpp
+./src/widgets.cpp
+./src/renderwindow.cpp
+)
+
+#find_package(SDL2 REQUIRED)
+include(FindPkgConfig)
+PKG_SEARCH_MODULE(SDL2 REQUIRED sdl2)
+PKG_SEARCH_MODULE(SDL2IMAGE REQUIRED SDL2_image>=2.0.0)
+PKG_SEARCH_MODULE(SDL2TTF REQUIRED SDL2_ttf>=2.0.0)
+PKG_SEARCH_MODULE(SDL2MIXER REQUIRED SDL2_mixer>=2.0.0)
+include_directories(${SDL2_INCLUDE_DIRS} ${SDL2IMAGE_INCLUDE_DIRS} ${SDL2TTF_INCLUDE_DIRS} ${SDL2MIXER_INCLUDE_DIRS} ${CMAKE_CURRENT_SOURCE_DIR}/include)
+
+# ping pong
+add_executable(ping_pong ${ENGINE_SRC} ${CMAKE_CURRENT_SOURCE_DIR}/games/Ping-Pong/src/main.cpp)
+target_link_libraries(ping_pong ${SDL2_LIBRARIES} ${SDL2IMAGE_LIBRARIES} ${SDL2TTF_LIBRARIES} ${SDL2MIXER_LIBRARIES})
+
+# editor
+add_executable(editor ${ENGINE_SRC} ${CMAKE_CURRENT_SOURCE_DIR}/editor/src/editor.cpp)
+target_link_libraries(editor ${SDL2_LIBRARIES} ${SDL2IMAGE_LIBRARIES} ${SDL2TTF_LIBRARIES} ${SDL2MIXER_LIBRARIES})
+
+# tests
+add_executable(run_tests ${ENGINE_SRC} ${CMAKE_CURRENT_SOURCE_DIR}/tests/src/tests.cpp)
+target_link_libraries(run_tests ${SDL2_LIBRARIES} ${SDL2IMAGE_LIBRARIES} ${SDL2TTF_LIBRARIES} ${SDL2MIXER_LIBRARIES})

LICENSE

@@ -0,0 +1,674 @@
+                    GNU GENERAL PUBLIC LICENSE
+                       Version 3, 29 June 2007
+
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+  Nothing in this License shall be construed as excluding or limiting
+any implied license or other defenses to infringement that may
+otherwise be available to you under applicable patent law.
+
+  12. No Surrender of Others' Freedom.
+
+  If conditions are imposed on you (whether by court order, agreement or
+otherwise) that contradict the conditions of this License, they do not
+excuse you from the conditions of this License.  If you cannot convey a
+covered work so as to satisfy simultaneously your obligations under this
+License and any other pertinent obligations, then as a consequence you may
+not convey it at all.  For example, if you agree to terms that obligate you
+to collect a royalty for further conveying from those to whom you convey
+the Program, the only way you could satisfy both those terms and this
+License would be to refrain entirely from conveying the Program.
+
+  13. Use with the GNU Affero General Public License.
+
+  Notwithstanding any other provision of this License, you have
+permission to link or combine any covered work with a work licensed
+under version 3 of the GNU Affero General Public License into a single
+combined work, and to convey the resulting work.  The terms of this
+License will continue to apply to the part which is the covered work,
+but the special requirements of the GNU Affero General Public License,
+section 13, concerning interaction through a network will apply to the
+combination as such.
+
+  14. Revised Versions of this License.
+
+  The Free Software Foundation may publish revised and/or new versions of
+the GNU General Public License from time to time.  Such new versions will
+be similar in spirit to the present version, but may differ in detail to
+address new problems or concerns.
+
+  Each version is given a distinguishing version number.  If the
+Program specifies that a certain numbered version of the GNU General
+Public License "or any later version" applies to it, you have the
+option of following the terms and conditions either of that numbered
+version or of any later version published by the Free Software
+Foundation.  If the Program does not specify a version number of the
+GNU General Public License, you may choose any version ever published
+by the Free Software Foundation.
+
+  If the Program specifies that a proxy can decide which future
+versions of the GNU General Public License can be used, that proxy's
+public statement of acceptance of a version permanently authorizes you
+to choose that version for the Program.
+
+  Later license versions may give you additional or different
+permissions.  However, no additional obligations are imposed on any
+author or copyright holder as a result of your choosing to follow a
+later version.
+
+  15. Disclaimer of Warranty.
+
+  THERE IS NO WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED BY
+APPLICABLE LAW.  EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT
+HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY
+OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO,
+THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+PURPOSE.  THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE PROGRAM
+IS WITH YOU.  SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF
+ALL NECESSARY SERVICING, REPAIR OR CORRECTION.
+
+  16. Limitation of Liability.
+
+  IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
+WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MODIFIES AND/OR CONVEYS
+THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY
+GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE
+USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF
+DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD
+PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS),
+EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF
+SUCH DAMAGES.
+
+  17. Interpretation of Sections 15 and 16.
+
+  If the disclaimer of warranty and limitation of liability provided
+above cannot be given local legal effect according to their terms,
+reviewing courts shall apply local law that most closely approximates
+an absolute waiver of all civil liability in connection with the
+Program, unless a warranty or assumption of liability accompanies a
+copy of the Program in return for a fee.
+
+                     END OF TERMS AND CONDITIONS
+
+            How to Apply These Terms to Your New Programs
+
+  If you develop a new program, and you want it to be of the greatest
+possible use to the public, the best way to achieve this is to make it
+free software which everyone can redistribute and change under these terms.
+
+  To do so, attach the following notices to the program.  It is safest
+to attach them to the start of each source file to most effectively
+state the exclusion of warranty; and each file should have at least
+the "copyright" line and a pointer to where the full notice is found.
+
+    <one line to give the program's name and a brief idea of what it does.>
+    Copyright (C) <year>  <name of author>
+
+    This program is free software: you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
+Also add information on how to contact you by electronic and paper mail.
+
+  If the program does terminal interaction, make it output a short
+notice like this when it starts in an interactive mode:
+
+    <program>  Copyright (C) <year>  <name of author>
+    This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
+    This is free software, and you are welcome to redistribute it
+    under certain conditions; type `show c' for details.
+
+The hypothetical commands `show w' and `show c' should show the appropriate
+parts of the General Public License.  Of course, your program's commands
+might be different; for a GUI interface, you would use an "about box".
+
+  You should also get your employer (if you work as a programmer) or school,
+if any, to sign a "copyright disclaimer" for the program, if necessary.
+For more information on this, and how to apply and follow the GNU GPL, see
+<https://www.gnu.org/licenses/>.
+
+  The GNU General Public License does not permit incorporating your program
+into proprietary programs.  If your program is a subroutine library, you
+may consider it more useful to permit linking proprietary applications with
+the library.  If this is what you want to do, use the GNU Lesser General
+Public License instead of this License.  But first, please read
+<https://www.gnu.org/licenses/why-not-lgpl.html>.

Makefile

@@ -0,0 +1,83 @@
+CC=g++
+SRCDIR=./src
+outputDir=./build
+binary=birb2d
+WarningFlags=-Wpedantic -pedantic -Wall -Wextra
+SDL_FLAGS=-lSDL2 -lSDL2main -lSDL2_image -lSDL2_ttf -lSDL2_mixer
+INCLUDES=-I./include
+
+all: final
+
+builddir:
+	mkdir -p ${outputDir}
+
+audio:
+	${CC} -c -g ${SRCDIR}/audio.cpp -lSDL2_mixer ${INCLUDES} ${WarningFlags} -o ${outputDir}/audio.o
+
+entity:
+	${CC} -c -g ${SRCDIR}/entity.cpp ${SDL_FLAGS} ${INCLUDES} ${WarningFlags} -o ${outputDir}/entity.o
+
+font:
+	${CC} -c -g ${SRCDIR}/font.cpp -lSDL2_ttf ${INCLUDES} ${WarningFlags} -o ${outputDir}/font.o
+
+renderwindow:
+	${CC} -c -g ${SRCDIR}/renderwindow.cpp ${SDL_FLAGS} ${INCLUDES} ${WarningFlags} -o ${outputDir}/renderwindow.o
+
+widgets:
+	${CC} -c -g ${SRCDIR}/widgets.cpp ${SDL_FLAGS} ${INCLUDES} ${WarningFlags} -o ${outputDir}/widgets.o
+
+values:
+	${CC} -c -g ${SRCDIR}/values.cpp -lSDL2 ${INCLUDES} ${WarningFlags} -o ${outputDir}/values.o
+
+logger:
+	${CC} -c -g ${SRCDIR}/logger.cpp ${INCLUDES} ${WarningFlags} -o ${outputDir}/logger.o
+
+utils:
+	${CC} -c -g ${SRCDIR}/utils.cpp ${INCLUDES} ${WarningFlags} -o ${outputDir}/utils.o
+
+scene:
+	${CC} -c -g ${SRCDIR}/scene.cpp ${INCLUDES} ${WarningFlags} ${SDL_FLAGS} -o ${outputDir}/scene.o
+
+doctest:
+	${CC} -c -g ./tests/src/tests.cpp ${INCLUDES} ${WarningFlags} ${SDL_FLAGS} -o ${outputDir}/tests.o
+
+test: builddir audio entity font renderwindow widgets values logger utils doctest
+	${CC} -g ${outputDir}/*.o ${SDL_FLAGS} -o ${outputDir}/${binary}_test
+	cd ${outputDir} ; ./${binary}_test
+
+
+ping-pong: builddir audio entity font renderwindow widgets values logger utils scene 
+	${CC} -g ./games/Ping-Pong/src/*.cpp ${outputDir}/*.o ${SDL_FLAGS} ${WarningFlags} -o ${outputDir}/ping-pong
+
+editor: builddir audio entity font renderwindow widgets values logger utils
+	${CC} -g ${outputDir}/*.o ./editor/src/editor.cpp ${SDL_FLAGS} ${WarningFlags} -o ${outputDir}/editor_playground
+
+final: builddir audio entity font renderwindow widgets values logger utils editor
+	${CC} -g ${outputDir}/*.o ${SDL_FLAGS} ${WarningFlags} -o ${outputDir}/editor
+
+win-editor: clean builddir
+	mkdir -p ${outputDir}/win
+	x86_64-w64-mingw32-g++ -DPLATFORM_WIN ./src/audio.cpp ./src/entity.cpp ./src/font.cpp ./src/renderwindow.cpp ./src/widgets.cpp ./src/values.cpp ./src/tests.cpp ${SDL_FLAGS} \
+		-I./vendor/SDL2_win/SDL2/x86_64-w64-mingw32/include \
+		-I./vendor/SDL2_win/SDL2_image-2.0.5/x86_64-w64-mingw32/include \
+		-I./vendor/SDL2_win/SDL2_mixer-2.0.4/x86_64-w64-mingw32/include \
+		-I./vendor/SDL2_win/SDL2_ttf-2.0.15/x86_64-w64-mingw32/include \
+		-L./vendor/SDL2_win/SDL2/x86_64-w64-mingw32/lib \
+		-L./vendor/SDL2_win/SDL2_image-2.0.5/x86_64-w64-mingw32/lib \
+		-L./vendor/SDL2_win/SDL2_mixer-2.0.4/x86_64-w64-mingw32/lib \
+		-L./vendor/SDL2_win/SDL2_ttf-2.0.15/x86_64-w64-mingw32/lib \
+		-L./vendor/mingw-w64-dlls-4.9.2/ \
+		-static-libgcc \
+		-static-libstdc++ \
+		-o ${outputDir}/win/editor_win.exe
+	cp ./vendor/SDL2_win/SDL2/x86_64-w64-mingw32/bin/*.dll ${outputDir}/win/
+	cp ./vendor/SDL2_win/SDL2_ttf-2.0.15/x86_64-w64-mingw32/bin/*.dll ${outputDir}/win/
+	cp ./vendor/SDL2_win/SDL2_image-2.0.5/x86_64-w64-mingw32/bin/*.dll ${outputDir}/win/
+	cp ./vendor/SDL2_win/SDL2_mixer-2.0.4/x86_64-w64-mingw32/bin/*.dll ${outputDir}/win/
+	cp ./vendor/mingw-w64-dlls-4.9.2/*.dll ${outputDir}/win/
+
+run:
+	cd ${outputDir} && ./editor
+
+clean:
+	rm -r ${outputDir}

README.md

@@ -0,0 +1,55 @@
+# Birb2D
+Birb2D is a simplistic 2D game engine made by an amateur programmer, with the goal to learn how game engines and development is done in more depth and from a complete behind the scenes perspective.
+
+Documentation coming soon(tm).
+
+## Games made with Birb2D
+- [Flappy Birb](https://github.com/Toasterbirb/Flappy-Birb)
+
+## External libraries
+- SDL2
+- doctest (included as a headerfile)
+
+## Building
+### Using CMake
+```sh
+mkdir build
+cd build
+cmake ..
+make -j4
+```
+
+### Using make (might be going away at some point)
+#### Editor
+```sh
+make -j4 editor
+```
+
+#### Ping Pong
+```sh
+make -j4 ping-pong
+```
+
+#### Run tests
+```sh
+make -j4 test
+```
+
+## Roadmap
+- [x] Sprite rendering
+- [x] Timestep
+- [x] Basic input handling (currently at cave man stage)
+- [x] Entity system (Partially functional currently)
+- [ ] Basic UI functionality
+	- [x] Buttons
+	- [x] Text
+	- [ ] Dropdown menu
+	- [ ] Slider
+	- [ ] Input box
+	- [x] Resizable UI
+		- [ ] Resolution independent UI scaling
+		- [ ] Anchors
+- [x] Sound
+- [ ] Animation
+- [ ] Physics
+- [ ] To be continued...

birb_project

@@ -0,0 +1,36 @@
+#!/bin/sh
+
+function _usage()
+{
+	echo "A simple project template creator for Birb2D"
+	echo "Commands:"
+	echo -e "  -o\tProject output path [required]"
+}
+
+function _createProject()
+{
+	mkdir -p $projectOutputPath
+	for i in $(<./project_template/dirlist)
+	do
+		mkdir -p "$projectOutputPath/$i"
+	done
+	cp ./project_template/Makefile $projectOutputPath/Makefile
+	cp ./project_template/main.cpp $projectOutputPath/src/main.cpp
+	mkdir $projectOutputPath/birb2d
+	ln -s $(pwd)/src $projectOutputPath/birb2d/src
+	ln -s $(pwd)/include $projectOutputPath/birb2d/include
+}
+
+for i in "$@"
+do
+	case $1 in
+		--help|help|-h|--h|-help) _usage ; exit 0 ;;
+		-o)
+			projectOutputPath=$2
+			shift 2
+			;;
+	esac
+done
+
+# Check if project name and output path was specified
+[ -n $projectOutputPath ] && _createProject || echo "Missing information to create a new project"

book/autodoc/Makefile

@@ -0,0 +1,2 @@
+final:
+	g++ -Wall -pedantic ./autodoc.cpp -o autodoc

book/autodoc/autodoc.cpp

@@ -0,0 +1,35 @@
+#include <iostream>
+#include <string.h>
+
+int main(int argc, char* argv[])
+{
+	int curLine = 0;
+	std::string output[2];
+	for (std::string line; std::getline(std::cin, line);)
+	{
+		if (curLine == 0)
+		{
+			output[0] = line;
+			curLine++;
+			continue;
+		}
+		else if (curLine == 1)
+		{
+			output[1] = line;
+			curLine++;
+
+			std::cout << "<details>\n" <<
+			"\t<summary>" << output[1] << "</summary>\n\n" <<
+			output[0] <<
+			"\n</details>\n";
+
+			curLine++;
+		}
+		else
+		{
+			curLine = 0;
+			continue;
+		}
+	}
+	return 0;
+}

book/book.toml

@@ -0,0 +1,12 @@
+[book]
+authors = ["Toasterbirb"]
+language = "en"
+multilingual = false
+src = "src"
+title = "Birb2D"
+
+[default]
+theme = "Navy"
+
+[build]
+build-dir = "../docs"

book/build.sh

@@ -0,0 +1,35 @@
+#!/bin/sh
+srcDir="../src"
+srcFiles=$(ls ${srcDir})
+buildDir="../book/src/autodoc"
+tableOfContentsFile=$buildDir/table_of_contents.md
+
+_genTableOfContents()
+{
+	echo "# Birb2D functions" > $tableOfContentsFile
+	echo "This file is generated automatically. Please don't modify it, it will be overwritten." >> $tableOfContentsFile
+	echo "## Files" >> $tableOfContentsFile
+}
+
+# Create the build target directory if it doesn't exist already
+[ -d $buildDir ] || mkdir -p $buildDir
+
+# Create table of contents file
+_genTableOfContents
+
+_addFileToTableOfContents()
+{
+	file=$1
+	fileName=$2
+	touch $buildDir/$fileName.md
+	echo "* [${fileName^}](./$fileName.md)" >> $tableOfContentsFile
+}
+
+echo "> Looking for documentation function comments..."
+for i in $srcFiles
+do
+	fileName=$(basename $i | cut -d'.' -f1)
+	mdfile=$buildDir/$fileName.md
+	echo "# ${fileName^}" > $mdfile
+	grep -A 1 "//\*\*" ${srcDir}/${i} | sed 's|//\*\* ||g' | ./autodoc/autodoc >> $mdfile && _addFileToTableOfContents $i $fileName
+done

book/src/SUMMARY.md

@@ -0,0 +1,4 @@
+# Summary
+
+- [Introduction](./introduction.md)
+- [Rendering](./rendering.md)

book/src/autodoc/audio.md

@@ -0,0 +1,16 @@
+# Audio
+<details>
+	<summary>bool Audio::initAudio(int flags)</summary>
+
+Initializes the SDL_mixer library. Needs to be called before any other audio features are used
+</details>
+<details>
+	<summary>MusicFile::MusicFile(std::string p_filePath)</summary>
+
+Loads up a music file from given path. Shouldn't be used for short sound effects
+</details>
+<details>
+	<summary>SoundFile::SoundFile(std::string p_filePath)</summary>
+
+Loads up a sound file from given path. Used for shorter sound effects and not music
+</details>

book/src/autodoc/entity.md

@@ -0,0 +1 @@
+# Entity

book/src/autodoc/events.md

@@ -0,0 +1 @@
+# Events

book/src/autodoc/font.md

@@ -0,0 +1 @@
+# Font

book/src/autodoc/logger.md

@@ -0,0 +1 @@
+# Logger

book/src/autodoc/math.md

@@ -0,0 +1 @@
+# Math

book/src/autodoc/renderwindow.md

@@ -0,0 +1 @@
+# Renderwindow

book/src/autodoc/scene.md

@@ -0,0 +1 @@
+# Scene

book/src/autodoc/table_of_contents.md

@@ -0,0 +1,14 @@
+# Birb2D functions
+This file is generated automatically. Please don't modify it, it will be overwritten.
+## Files
+* [Audio](./audio.md)
+* [Entity](./entity.md)
+* [Events](./events.md)
+* [Font](./font.md)
+* [Logger](./logger.md)
+* [Math](./math.md)
+* [Renderwindow](./renderwindow.md)
+* [Scene](./scene.md)
+* [Utils](./utils.md)
+* [Values](./values.md)
+* [Widgets](./widgets.md)

book/src/autodoc/utils.md

@@ -0,0 +1 @@
+# Utils

book/src/autodoc/values.md

@@ -0,0 +1 @@
+# Values

book/src/autodoc/widgets.md

@@ -0,0 +1 @@
+# Widgets

book/src/introduction.md

@@ -0,0 +1 @@
+# Introduction

book/src/rendering.md

@@ -0,0 +1,4 @@
+# Rendering
+
+## Entity system
+![entity_system](./pictures/Rendering_system.png)

compile_flags.txt

@@ -0,0 +1 @@
+-I./include

continuous_testing.sh

@@ -0,0 +1,4 @@
+#!/bin/sh
+mkdir -p build
+cd build
+find ../src/ -print | entr -sc 'cd .. ; make -j4 test && cd build ; ./birb2d_test'

docs/.nojekyll

@@ -0,0 +1 @@
+This file makes sure that Github Pages doesn't process mdBook's output.

docs/404.html

@@ -0,0 +1,167 @@
+<!DOCTYPE HTML>
+<html lang="en" class="sidebar-visible no-js light">
+    <head>
+        <!-- Book generated using mdBook -->
+        <meta charset="UTF-8">
+        <title></title>
+        <base href="/">
+        <!-- Custom HTML head -->
+        <meta content="text/html; charset=utf-8" http-equiv="Content-Type">
+        <meta name="description" content="">
+        <meta name="viewport" content="width=device-width, initial-scale=1">
+        <meta name="theme-color" content="#ffffff" />
+
+        <link rel="icon" href="favicon.svg">
+        <link rel="shortcut icon" href="favicon.png">
+        <link rel="stylesheet" href="css/variables.css">
+        <link rel="stylesheet" href="css/general.css">
+        <link rel="stylesheet" href="css/chrome.css">
+        <link rel="stylesheet" href="css/print.css" media="print">
+        <!-- Fonts -->
+        <link rel="stylesheet" href="FontAwesome/css/font-awesome.css">
+        <link rel="stylesheet" href="fonts/fonts.css">
+        <!-- Highlight.js Stylesheets -->
+        <link rel="stylesheet" href="highlight.css">
+        <link rel="stylesheet" href="tomorrow-night.css">
+        <link rel="stylesheet" href="ayu-highlight.css">
+
+        <!-- Custom theme stylesheets -->
+    </head>
+    <body>
+        <!-- Provide site root to javascript -->
+        <script type="text/javascript">
+            var path_to_root = "";
+            var default_theme = window.matchMedia("(prefers-color-scheme: dark)").matches ? "navy" : "light";
+        </script>
+
+        <!-- Work around some values being stored in localStorage wrapped in quotes -->
+        <script type="text/javascript">
+            try {
+                var theme = localStorage.getItem('mdbook-theme');
+                var sidebar = localStorage.getItem('mdbook-sidebar');
+
+                if (theme.startsWith('"') && theme.endsWith('"')) {
+                    localStorage.setItem('mdbook-theme', theme.slice(1, theme.length - 1));
+                }
+
+                if (sidebar.startsWith('"') && sidebar.endsWith('"')) {
+                    localStorage.setItem('mdbook-sidebar', sidebar.slice(1, sidebar.length - 1));
+                }
+            } catch (e) { }
+        </script>
+
+        <!-- Set the theme before any content is loaded, prevents flash -->
+        <script type="text/javascript">
+            var theme;
+            try { theme = localStorage.getItem('mdbook-theme'); } catch(e) { }
+            if (theme === null || theme === undefined) { theme = default_theme; }
+            var html = document.querySelector('html');
+            html.classList.remove('no-js')
+            html.classList.remove('light')
+            html.classList.add(theme);
+            html.classList.add('js');
+        </script>
+
+        <!-- Hide / unhide sidebar before it is displayed -->
+        <script type="text/javascript">
+            var html = document.querySelector('html');
+            var sidebar = 'hidden';
+            if (document.body.clientWidth >= 1080) {
+                try { sidebar = localStorage.getItem('mdbook-sidebar'); } catch(e) { }
+                sidebar = sidebar || 'visible';
+            }
+            html.classList.remove('sidebar-visible');
+            html.classList.add("sidebar-" + sidebar);
+        </script>
+
+        <nav id="sidebar" class="sidebar" aria-label="Table of contents">
+            <div class="sidebar-scrollbox">
+                <ol class="chapter"><li class="chapter-item expanded "><a href="introduction.html"><strong aria-hidden="true">1.</strong> Introduction</a></li><li class="chapter-item expanded "><a href="rendering.html"><strong aria-hidden="true">2.</strong> Rendering</a></li></ol>
+            </div>
+            <div id="sidebar-resize-handle" class="sidebar-resize-handle"></div>
+        </nav>
+
+        <div id="page-wrapper" class="page-wrapper">
+
+            <div class="page">
+                <div id="menu-bar-hover-placeholder"></div>
+                <div id="menu-bar" class="menu-bar sticky bordered">
+                    <div class="left-buttons">
+                        <button id="sidebar-toggle" class="icon-button" type="button" title="Toggle Table of Contents" aria-label="Toggle Table of Contents" aria-controls="sidebar">
+                            <i class="fa fa-bars"></i>
+                        </button>
+                        <button id="theme-toggle" class="icon-button" type="button" title="Change theme" aria-label="Change theme" aria-haspopup="true" aria-expanded="false" aria-controls="theme-list">
+                            <i class="fa fa-paint-brush"></i>
+                        </button>
+                        <ul id="theme-list" class="theme-popup" aria-label="Themes" role="menu">
+                            <li role="none"><button role="menuitem" class="theme" id="light">Light (default)</button></li>
+                            <li role="none"><button role="menuitem" class="theme" id="rust">Rust</button></li>
+                            <li role="none"><button role="menuitem" class="theme" id="coal">Coal</button></li>
+                            <li role="none"><button role="menuitem" class="theme" id="navy">Navy</button></li>
+                            <li role="none"><button role="menuitem" class="theme" id="ayu">Ayu</button></li>
+                        </ul>
+                        <button id="search-toggle" class="icon-button" type="button" title="Search. (Shortkey: s)" aria-label="Toggle Searchbar" aria-expanded="false" aria-keyshortcuts="S" aria-controls="searchbar">
+                            <i class="fa fa-search"></i>
+                        </button>
+                    </div>
+
+                    <h1 class="menu-title">Birb2D</h1>
+
+                    <div class="right-buttons">
+                        <a href="print.html" title="Print this book" aria-label="Print this book">
+                            <i id="print-button" class="fa fa-print"></i>
+                        </a>
+                    </div>
+                </div>
+
+                <div id="search-wrapper" class="hidden">
+                    <form id="searchbar-outer" class="searchbar-outer">
+                        <input type="search" id="searchbar" name="searchbar" placeholder="Search this book ..." aria-controls="searchresults-outer" aria-describedby="searchresults-header">
+                    </form>
+                    <div id="searchresults-outer" class="searchresults-outer hidden">
+                        <div id="searchresults-header" class="searchresults-header"></div>
+                        <ul id="searchresults">
+                        </ul>
+                    </div>
+                </div>
+                <!-- Apply ARIA attributes after the sidebar and the sidebar toggle button are added to the DOM -->
+                <script type="text/javascript">
+                    document.getElementById('sidebar-toggle').setAttribute('aria-expanded', sidebar === 'visible');
+                    document.getElementById('sidebar').setAttribute('aria-hidden', sidebar !== 'visible');
+                    Array.from(document.querySelectorAll('#sidebar a')).forEach(function(link) {
+                        link.setAttribute('tabIndex', sidebar === 'visible' ? 0 : -1);
+                    });
+                </script>
+
+                <div id="content" class="content">
+                    <main>
+                        <h1 id="document-not-found-404"><a class="header" href="#document-not-found-404">Document not found (404)</a></h1>
+<p>This URL is invalid, sorry. Please use the navigation bar or search to continue.</p>
+
+                    </main>
+
+                    <nav class="nav-wrapper" aria-label="Page navigation">
+                        <!-- Mobile navigation buttons -->
+                        <div style="clear: both"></div>
+                    </nav>
+                </div>
+            </div>
+
+            <nav class="nav-wide-wrapper" aria-label="Page navigation">
+            </nav>
+
+        </div>
+
+        <script type="text/javascript">
+            window.playground_copyable = true;
+        </script>
+        <script src="elasticlunr.min.js" type="text/javascript" charset="utf-8"></script>
+        <script src="mark.min.js" type="text/javascript" charset="utf-8"></script>
+        <script src="searcher.js" type="text/javascript" charset="utf-8"></script>
+        <script src="clipboard.min.js" type="text/javascript" charset="utf-8"></script>
+        <script src="highlight.js" type="text/javascript" charset="utf-8"></script>
+        <script src="book.js" type="text/javascript" charset="utf-8"></script>
+
+        <!-- Custom JS scripts -->
+    </body>
+</html>

docs/ayu-highlight.css

@@ -0,0 +1,79 @@
+/*
+Based off of the Ayu theme
+Original by Dempfi (https://github.com/dempfi/ayu)
+*/
+
+.hljs {
+  display: block;
+  overflow-x: auto;
+  background: #191f26;
+  color: #e6e1cf;
+  padding: 0.5em;
+}
+
+.hljs-comment,
+.hljs-quote {
+  color: #5c6773;
+  font-style: italic;
+}
+
+.hljs-variable,
+.hljs-template-variable,
+.hljs-attribute,
+.hljs-attr,
+.hljs-regexp,
+.hljs-link,
+.hljs-selector-id,
+.hljs-selector-class {
+  color: #ff7733;
+}
+
+.hljs-number,
+.hljs-meta,
+.hljs-builtin-name,
+.hljs-literal,
+.hljs-type,
+.hljs-params {
+  color: #ffee99;
+}
+
+.hljs-string,
+.hljs-bullet {
+  color: #b8cc52;
+}
+
+.hljs-title,
+.hljs-built_in,
+.hljs-section {
+  color: #ffb454;
+}
+
+.hljs-keyword,
+.hljs-selector-tag,
+.hljs-symbol {
+  color: #ff7733;
+}
+
+.hljs-name {
+    color: #36a3d9;
+}
+
+.hljs-tag {
+    color: #00568d;
+}
+
+.hljs-emphasis {
+  font-style: italic;
+}
+
+.hljs-strong {
+  font-weight: bold;
+}
+
+.hljs-addition {
+  color: #91b362;
+}
+
+.hljs-deletion {
+  color: #d96c75;
+}

docs/book.js

@@ -0,0 +1,679 @@
+"use strict";
+
+// Fix back button cache problem
+window.onunload = function () { };
+
+// Global variable, shared between modules
+function playground_text(playground) {
+    let code_block = playground.querySelector("code");
+
+    if (window.ace && code_block.classList.contains("editable")) {
+        let editor = window.ace.edit(code_block);
+        return editor.getValue();
+    } else {
+        return code_block.textContent;
+    }
+}
+
+(function codeSnippets() {
+    function fetch_with_timeout(url, options, timeout = 6000) {
+        return Promise.race([
+            fetch(url, options),
+            new Promise((_, reject) => setTimeout(() => reject(new Error('timeout')), timeout))
+        ]);
+    }
+
+    var playgrounds = Array.from(document.querySelectorAll(".playground"));
+    if (playgrounds.length > 0) {
+        fetch_with_timeout("https://play.rust-lang.org/meta/crates", {
+            headers: {
+                'Content-Type': "application/json",
+            },
+            method: 'POST',
+            mode: 'cors',
+        })
+        .then(response => response.json())
+        .then(response => {
+            // get list of crates available in the rust playground
+            let playground_crates = response.crates.map(item => item["id"]);
+            playgrounds.forEach(block => handle_crate_list_update(block, playground_crates));
+        });
+    }
+
+    function handle_crate_list_update(playground_block, playground_crates) {
+        // update the play buttons after receiving the response
+        update_play_button(playground_block, playground_crates);
+
+        // and install on change listener to dynamically update ACE editors
+        if (window.ace) {
+            let code_block = playground_block.querySelector("code");
+            if (code_block.classList.contains("editable")) {
+                let editor = window.ace.edit(code_block);
+                editor.addEventListener("change", function (e) {
+                    update_play_button(playground_block, playground_crates);
+                });
+                // add Ctrl-Enter command to execute rust code
+                editor.commands.addCommand({
+                    name: "run",
+                    bindKey: {
+                        win: "Ctrl-Enter",
+                        mac: "Ctrl-Enter"
+                    },
+                    exec: _editor => run_rust_code(playground_block)
+                });
+            }
+        }
+    }
+
+    // updates the visibility of play button based on `no_run` class and
+    // used crates vs ones available on http://play.rust-lang.org
+    function update_play_button(pre_block, playground_crates) {
+        var play_button = pre_block.querySelector(".play-button");
+
+        // skip if code is `no_run`
+        if (pre_block.querySelector('code').classList.contains("no_run")) {
+            play_button.classList.add("hidden");
+            return;
+        }
+
+        // get list of `extern crate`'s from snippet
+        var txt = playground_text(pre_block);
+        var re = /extern\s+crate\s+([a-zA-Z_0-9]+)\s*;/g;
+        var snippet_crates = [];
+        var item;
+        while (item = re.exec(txt)) {
+            snippet_crates.push(item[1]);
+        }
+
+        // check if all used crates are available on play.rust-lang.org
+        var all_available = snippet_crates.every(function (elem) {
+            return playground_crates.indexOf(elem) > -1;
+        });
+
+        if (all_available) {
+            play_button.classList.remove("hidden");
+        } else {
+            play_button.classList.add("hidden");
+        }
+    }
+
+    function run_rust_code(code_block) {
+        var result_block = code_block.querySelector(".result");
+        if (!result_block) {
+            result_block = document.createElement('code');
+            result_block.className = 'result hljs language-bash';
+
+            code_block.append(result_block);
+        }
+
+        let text = playground_text(code_block);
+        let classes = code_block.querySelector('code').classList;
+        let edition = "2015";
+        if(classes.contains("edition2018")) {
+            edition = "2018";
+        } else if(classes.contains("edition2021")) {
+            edition = "2021";
+        }
+        var params = {
+            version: "stable",
+            optimize: "0",
+            code: text,
+            edition: edition
+        };
+
+        if (text.indexOf("#![feature") !== -1) {
+            params.version = "nightly";
+        }
+
+        result_block.innerText = "Running...";
+
+        fetch_with_timeout("https://play.rust-lang.org/evaluate.json", {
+            headers: {
+                'Content-Type': "application/json",
+            },
+            method: 'POST',
+            mode: 'cors',
+            body: JSON.stringify(params)
+        })
+        .then(response => response.json())
+        .then(response => {
+            if (response.result.trim() === '') {
+                result_block.innerText = "No output";
+                result_block.classList.add("result-no-output");
+            } else {
+                result_block.innerText = response.result;
+                result_block.classList.remove("result-no-output");
+            }
+        })
+        .catch(error => result_block.innerText = "Playground Communication: " + error.message);
+    }
+
+    // Syntax highlighting Configuration
+    hljs.configure({
+        tabReplace: '    ', // 4 spaces
+        languages: [],      // Languages used for auto-detection
+    });
+
+    let code_nodes = Array
+        .from(document.querySelectorAll('code'))
+        // Don't highlight `inline code` blocks in headers.
+        .filter(function (node) {return !node.parentElement.classList.contains("header"); });
+
+    if (window.ace) {
+        // language-rust class needs to be removed for editable
+        // blocks or highlightjs will capture events
+        code_nodes
+            .filter(function (node) {return node.classList.contains("editable"); })
+            .forEach(function (block) { block.classList.remove('language-rust'); });
+
+        Array
+        code_nodes
+            .filter(function (node) {return !node.classList.contains("editable"); })
+            .forEach(function (block) { hljs.highlightBlock(block); });
+    } else {
+        code_nodes.forEach(function (block) { hljs.highlightBlock(block); });
+    }
+
+    // Adding the hljs class gives code blocks the color css
+    // even if highlighting doesn't apply
+    code_nodes.forEach(function (block) { block.classList.add('hljs'); });
+
+    Array.from(document.querySelectorAll("code.language-rust")).forEach(function (block) {
+
+        var lines = Array.from(block.querySelectorAll('.boring'));
+        // If no lines were hidden, return
+        if (!lines.length) { return; }
+        block.classList.add("hide-boring");
+
+        var buttons = document.createElement('div');
+        buttons.className = 'buttons';
+        buttons.innerHTML = "<button class=\"fa fa-eye\" title=\"Show hidden lines\" aria-label=\"Show hidden lines\"></button>";
+
+        // add expand button
+        var pre_block = block.parentNode;
+        pre_block.insertBefore(buttons, pre_block.firstChild);
+
+        pre_block.querySelector('.buttons').addEventListener('click', function (e) {
+            if (e.target.classList.contains('fa-eye')) {
+                e.target.classList.remove('fa-eye');
+                e.target.classList.add('fa-eye-slash');
+                e.target.title = 'Hide lines';
+                e.target.setAttribute('aria-label', e.target.title);
+
+                block.classList.remove('hide-boring');
+            } else if (e.target.classList.contains('fa-eye-slash')) {
+                e.target.classList.remove('fa-eye-slash');
+                e.target.classList.add('fa-eye');
+                e.target.title = 'Show hidden lines';
+                e.target.setAttribute('aria-label', e.target.title);
+
+                block.classList.add('hide-boring');
+            }
+        });
+    });
+
+    if (window.playground_copyable) {
+        Array.from(document.querySelectorAll('pre code')).forEach(function (block) {
+            var pre_block = block.parentNode;
+            if (!pre_block.classList.contains('playground')) {
+                var buttons = pre_block.querySelector(".buttons");
+                if (!buttons) {
+                    buttons = document.createElement('div');
+                    buttons.className = 'buttons';
+                    pre_block.insertBefore(buttons, pre_block.firstChild);
+                }
+
+                var clipButton = document.createElement('button');
+                clipButton.className = 'fa fa-copy clip-button';
+                clipButton.title = 'Copy to clipboard';
+                clipButton.setAttribute('aria-label', clipButton.title);
+                clipButton.innerHTML = '<i class=\"tooltiptext\"></i>';
+
+                buttons.insertBefore(clipButton, buttons.firstChild);
+            }
+        });
+    }
+
+    // Process playground code blocks
+    Array.from(document.querySelectorAll(".playground")).forEach(function (pre_block) {
+        // Add play button
+        var buttons = pre_block.querySelector(".buttons");
+        if (!buttons) {
+            buttons = document.createElement('div');
+            buttons.className = 'buttons';
+            pre_block.insertBefore(buttons, pre_block.firstChild);
+        }
+
+        var runCodeButton = document.createElement('button');
+        runCodeButton.className = 'fa fa-play play-button';
+        runCodeButton.hidden = true;
+        runCodeButton.title = 'Run this code';
+        runCodeButton.setAttribute('aria-label', runCodeButton.title);
+
+        buttons.insertBefore(runCodeButton, buttons.firstChild);
+        runCodeButton.addEventListener('click', function (e) {
+            run_rust_code(pre_block);
+        });
+
+        if (window.playground_copyable) {
+            var copyCodeClipboardButton = document.createElement('button');
+            copyCodeClipboardButton.className = 'fa fa-copy clip-button';
+            copyCodeClipboardButton.innerHTML = '<i class="tooltiptext"></i>';
+            copyCodeClipboardButton.title = 'Copy to clipboard';
+            copyCodeClipboardButton.setAttribute('aria-label', copyCodeClipboardButton.title);
+
+            buttons.insertBefore(copyCodeClipboardButton, buttons.firstChild);
+        }
+
+        let code_block = pre_block.querySelector("code");
+        if (window.ace && code_block.classList.contains("editable")) {
+            var undoChangesButton = document.createElement('button');
+            undoChangesButton.className = 'fa fa-history reset-button';
+            undoChangesButton.title = 'Undo changes';
+            undoChangesButton.setAttribute('aria-label', undoChangesButton.title);
+
+            buttons.insertBefore(undoChangesButton, buttons.firstChild);
+
+            undoChangesButton.addEventListener('click', function () {
+                let editor = window.ace.edit(code_block);
+                editor.setValue(editor.originalCode);
+                editor.clearSelection();
+            });
+        }
+    });
+})();
+
+(function themes() {
+    var html = document.querySelector('html');
+    var themeToggleButton = document.getElementById('theme-toggle');
+    var themePopup = document.getElementById('theme-list');
+    var themeColorMetaTag = document.querySelector('meta[name="theme-color"]');
+    var stylesheets = {
+        ayuHighlight: document.querySelector("[href$='ayu-highlight.css']"),
+        tomorrowNight: document.querySelector("[href$='tomorrow-night.css']"),
+        highlight: document.querySelector("[href$='highlight.css']"),
+    };
+
+    function showThemes() {
+        themePopup.style.display = 'block';
+        themeToggleButton.setAttribute('aria-expanded', true);
+        themePopup.querySelector("button#" + get_theme()).focus();
+    }
+
+    function hideThemes() {
+        themePopup.style.display = 'none';
+        themeToggleButton.setAttribute('aria-expanded', false);
+        themeToggleButton.focus();
+    }
+
+    function get_theme() {
+        var theme;
+        try { theme = localStorage.getItem('mdbook-theme'); } catch (e) { }
+        if (theme === null || theme === undefined) {
+            return default_theme;
+        } else {
+            return theme;
+        }
+    }
+
+    function set_theme(theme, store = true) {
+        let ace_theme;
+
+        if (theme == 'coal' || theme == 'navy') {
+            stylesheets.ayuHighlight.disabled = true;
+            stylesheets.tomorrowNight.disabled = false;
+            stylesheets.highlight.disabled = true;
+
+            ace_theme = "ace/theme/tomorrow_night";
+        } else if (theme == 'ayu') {
+            stylesheets.ayuHighlight.disabled = false;
+            stylesheets.tomorrowNight.disabled = true;
+            stylesheets.highlight.disabled = true;
+            ace_theme = "ace/theme/tomorrow_night";
+        } else {
+            stylesheets.ayuHighlight.disabled = true;
+            stylesheets.tomorrowNight.disabled = true;
+            stylesheets.highlight.disabled = false;
+            ace_theme = "ace/theme/dawn";
+        }
+
+        setTimeout(function () {
+            themeColorMetaTag.content = getComputedStyle(document.body).backgroundColor;
+        }, 1);
+
+        if (window.ace && window.editors) {
+            window.editors.forEach(function (editor) {
+                editor.setTheme(ace_theme);
+            });
+        }
+
+        var previousTheme = get_theme();
+
+        if (store) {
+            try { localStorage.setItem('mdbook-theme', theme); } catch (e) { }
+        }
+
+        html.classList.remove(previousTheme);
+        html.classList.add(theme);
+    }
+
+    // Set theme
+    var theme = get_theme();
+
+    set_theme(theme, false);
+
+    themeToggleButton.addEventListener('click', function () {
+        if (themePopup.style.display === 'block') {
+            hideThemes();
+        } else {
+            showThemes();
+        }
+    });
+
+    themePopup.addEventListener('click', function (e) {
+        var theme;
+        if (e.target.className === "theme") {
+            theme = e.target.id;
+        } else if (e.target.parentElement.className === "theme") {
+            theme = e.target.parentElement.id;
+        } else {
+            return;
+        }
+        set_theme(theme);
+    });
+
+    themePopup.addEventListener('focusout', function(e) {
+        // e.relatedTarget is null in Safari and Firefox on macOS (see workaround below)
+        if (!!e.relatedTarget && !themeToggleButton.contains(e.relatedTarget) && !themePopup.contains(e.relatedTarget)) {
+            hideThemes();
+        }
+    });
+
+    // Should not be needed, but it works around an issue on macOS & iOS: https://github.com/rust-lang/mdBook/issues/628
+    document.addEventListener('click', function(e) {
+        if (themePopup.style.display === 'block' && !themeToggleButton.contains(e.target) && !themePopup.contains(e.target)) {
+            hideThemes();
+        }
+    });
+
+    document.addEventListener('keydown', function (e) {
+        if (e.altKey || e.ctrlKey || e.metaKey || e.shiftKey) { return; }
+        if (!themePopup.contains(e.target)) { return; }
+
+        switch (e.key) {
+            case 'Escape':
+                e.preventDefault();
+                hideThemes();
+                break;
+            case 'ArrowUp':
+                e.preventDefault();
+                var li = document.activeElement.parentElement;
+                if (li && li.previousElementSibling) {
+                    li.previousElementSibling.querySelector('button').focus();
+                }
+                break;
+            case 'ArrowDown':
+                e.preventDefault();
+                var li = document.activeElement.parentElement;
+                if (li && li.nextElementSibling) {
+                    li.nextElementSibling.querySelector('button').focus();
+                }
+                break;
+            case 'Home':
+                e.preventDefault();
+                themePopup.querySelector('li:first-child button').focus();
+                break;
+            case 'End':
+                e.preventDefault();
+                themePopup.querySelector('li:last-child button').focus();
+                break;
+        }
+    });
+})();
+
+(function sidebar() {
+    var html = document.querySelector("html");
+    var sidebar = document.getElementById("sidebar");
+    var sidebarLinks = document.querySelectorAll('#sidebar a');
+    var sidebarToggleButton = document.getElementById("sidebar-toggle");
+    var sidebarResizeHandle = document.getElementById("sidebar-resize-handle");
+    var firstContact = null;
+
+    function showSidebar() {
+        html.classList.remove('sidebar-hidden')
+        html.classList.add('sidebar-visible');
+        Array.from(sidebarLinks).forEach(function (link) {
+            link.setAttribute('tabIndex', 0);
+        });
+        sidebarToggleButton.setAttribute('aria-expanded', true);
+        sidebar.setAttribute('aria-hidden', false);
+        try { localStorage.setItem('mdbook-sidebar', 'visible'); } catch (e) { }
+    }
+
+
+    var sidebarAnchorToggles = document.querySelectorAll('#sidebar a.toggle');
+
+    function toggleSection(ev) {
+        ev.currentTarget.parentElement.classList.toggle('expanded');
+    }
+
+    Array.from(sidebarAnchorToggles).forEach(function (el) {
+        el.addEventListener('click', toggleSection);
+    });
+
+    function hideSidebar() {
+        html.classList.remove('sidebar-visible')
+        html.classList.add('sidebar-hidden');
+        Array.from(sidebarLinks).forEach(function (link) {
+            link.setAttribute('tabIndex', -1);
+        });
+        sidebarToggleButton.setAttribute('aria-expanded', false);
+        sidebar.setAttribute('aria-hidden', true);
+        try { localStorage.setItem('mdbook-sidebar', 'hidden'); } catch (e) { }
+    }
+
+    // Toggle sidebar
+    sidebarToggleButton.addEventListener('click', function sidebarToggle() {
+        if (html.classList.contains("sidebar-hidden")) {
+            var current_width = parseInt(
+                document.documentElement.style.getPropertyValue('--sidebar-width'), 10);
+            if (current_width < 150) {
+                document.documentElement.style.setProperty('--sidebar-width', '150px');
+            }
+            showSidebar();
+        } else if (html.classList.contains("sidebar-visible")) {
+            hideSidebar();
+        } else {
+            if (getComputedStyle(sidebar)['transform'] === 'none') {
+                hideSidebar();
+            } else {
+                showSidebar();
+            }
+        }
+    });
+
+    sidebarResizeHandle.addEventListener('mousedown', initResize, false);
+
+    function initResize(e) {
+        window.addEventListener('mousemove', resize, false);
+        window.addEventListener('mouseup', stopResize, false);
+        html.classList.add('sidebar-resizing');
+    }
+    function resize(e) {
+        var pos = (e.clientX - sidebar.offsetLeft);
+        if (pos < 20) {
+            hideSidebar();
+        } else {
+            if (html.classList.contains("sidebar-hidden")) {
+                showSidebar();
+            }
+            pos = Math.min(pos, window.innerWidth - 100);
+            document.documentElement.style.setProperty('--sidebar-width', pos + 'px');
+        }
+    }
+    //on mouseup remove windows functions mousemove & mouseup
+    function stopResize(e) {
+        html.classList.remove('sidebar-resizing');
+        window.removeEventListener('mousemove', resize, false);
+        window.removeEventListener('mouseup', stopResize, false);
+    }
+
+    document.addEventListener('touchstart', function (e) {
+        firstContact = {
+            x: e.touches[0].clientX,
+            time: Date.now()
+        };
+    }, { passive: true });
+
+    document.addEventListener('touchmove', function (e) {
+        if (!firstContact)
+            return;
+
+        var curX = e.touches[0].clientX;
+        var xDiff = curX - firstContact.x,
+            tDiff = Date.now() - firstContact.time;
+
+        if (tDiff < 250 && Math.abs(xDiff) >= 150) {
+            if (xDiff >= 0 && firstContact.x < Math.min(document.body.clientWidth * 0.25, 300))
+                showSidebar();
+            else if (xDiff < 0 && curX < 300)
+                hideSidebar();
+
+            firstContact = null;
+        }
+    }, { passive: true });
+
+    // Scroll sidebar to current active section
+    var activeSection = document.getElementById("sidebar").querySelector(".active");
+    if (activeSection) {
+        // https://developer.mozilla.org/en-US/docs/Web/API/Element/scrollIntoView
+        activeSection.scrollIntoView({ block: 'center' });
+    }
+})();
+
+(function chapterNavigation() {
+    document.addEventListener('keydown', function (e) {
+        if (e.altKey || e.ctrlKey || e.metaKey || e.shiftKey) { return; }
+        if (window.search && window.search.hasFocus()) { return; }
+
+        switch (e.key) {
+            case 'ArrowRight':
+                e.preventDefault();
+                var nextButton = document.querySelector('.nav-chapters.next');
+                if (nextButton) {
+                    window.location.href = nextButton.href;
+                }
+                break;
+            case 'ArrowLeft':
+                e.preventDefault();
+                var previousButton = document.querySelector('.nav-chapters.previous');
+                if (previousButton) {
+                    window.location.href = previousButton.href;
+                }
+                break;
+        }
+    });
+})();
+
+(function clipboard() {
+    var clipButtons = document.querySelectorAll('.clip-button');
+
+    function hideTooltip(elem) {
+        elem.firstChild.innerText = "";
+        elem.className = 'fa fa-copy clip-button';
+    }
+
+    function showTooltip(elem, msg) {
+        elem.firstChild.innerText = msg;
+        elem.className = 'fa fa-copy tooltipped';
+    }
+
+    var clipboardSnippets = new ClipboardJS('.clip-button', {
+        text: function (trigger) {
+            hideTooltip(trigger);
+            let playground = trigger.closest("pre");
+            return playground_text(playground);
+        }
+    });
+
+    Array.from(clipButtons).forEach(function (clipButton) {
+        clipButton.addEventListener('mouseout', function (e) {
+            hideTooltip(e.currentTarget);
+        });
+    });
+
+    clipboardSnippets.on('success', function (e) {
+        e.clearSelection();
+        showTooltip(e.trigger, "Copied!");
+    });
+
+    clipboardSnippets.on('error', function (e) {
+        showTooltip(e.trigger, "Clipboard error!");
+    });
+})();
+
+(function scrollToTop () {
+    var menuTitle = document.querySelector('.menu-title');
+
+    menuTitle.addEventListener('click', function () {
+        document.scrollingElement.scrollTo({ top: 0, behavior: 'smooth' });
+    });
+})();
+
+(function controllMenu() {
+    var menu = document.getElementById('menu-bar');
+
+    (function controllPosition() {
+        var scrollTop = document.scrollingElement.scrollTop;
+        var prevScrollTop = scrollTop;
+        var minMenuY = -menu.clientHeight - 50;
+        // When the script loads, the page can be at any scroll (e.g. if you reforesh it).
+        menu.style.top = scrollTop + 'px';
+        // Same as parseInt(menu.style.top.slice(0, -2), but faster
+        var topCache = menu.style.top.slice(0, -2);
+        menu.classList.remove('sticky');
+        var stickyCache = false; // Same as menu.classList.contains('sticky'), but faster
+        document.addEventListener('scroll', function () {
+            scrollTop = Math.max(document.scrollingElement.scrollTop, 0);
+            // `null` means that it doesn't need to be updated
+            var nextSticky = null;
+            var nextTop = null;
+            var scrollDown = scrollTop > prevScrollTop;
+            var menuPosAbsoluteY = topCache - scrollTop;
+            if (scrollDown) {
+                nextSticky = false;
+                if (menuPosAbsoluteY > 0) {
+                    nextTop = prevScrollTop;
+                }
+            } else {
+                if (menuPosAbsoluteY > 0) {
+                    nextSticky = true;
+                } else if (menuPosAbsoluteY < minMenuY) {
+                    nextTop = prevScrollTop + minMenuY;
+                }
+            }
+            if (nextSticky === true && stickyCache === false) {
+                menu.classList.add('sticky');
+                stickyCache = true;
+            } else if (nextSticky === false && stickyCache === true) {
+                menu.classList.remove('sticky');
+                stickyCache = false;
+            }
+            if (nextTop !== null) {
+                menu.style.top = nextTop + 'px';
+                topCache = nextTop;
+            }
+            prevScrollTop = scrollTop;
+        }, { passive: true });
+    })();
+    (function controllBorder() {
+        menu.classList.remove('bordered');
+        document.addEventListener('scroll', function () {
+            if (menu.offsetTop === 0) {
+                menu.classList.remove('bordered');
+            } else {
+                menu.classList.add('bordered');
+            }
+        }, { passive: true });
+    })();
+})();

docs/css/chrome.css

@@ -0,0 +1,495 @@
+/* CSS for UI elements (a.k.a. chrome) */
+
+@import 'variables.css';
+
+::-webkit-scrollbar {
+    background: var(--bg);
+}
+::-webkit-scrollbar-thumb {
+    background: var(--scrollbar);
+}
+html {
+    scrollbar-color: var(--scrollbar) var(--bg);
+}
+#searchresults a,
+.content a:link,
+a:visited,
+a > .hljs {
+    color: var(--links);
+}
+
+/* Menu Bar */
+
+#menu-bar,
+#menu-bar-hover-placeholder {
+    z-index: 101;
+    margin: auto calc(0px - var(--page-padding));
+}
+#menu-bar {
+    position: relative;
+    display: flex;
+    flex-wrap: wrap;
+    background-color: var(--bg);
+    border-bottom-color: var(--bg);
+    border-bottom-width: 1px;
+    border-bottom-style: solid;
+}
+#menu-bar.sticky,
+.js #menu-bar-hover-placeholder:hover + #menu-bar,
+.js #menu-bar:hover,
+.js.sidebar-visible #menu-bar {
+    position: -webkit-sticky;
+    position: sticky;
+    top: 0 !important;
+}
+#menu-bar-hover-placeholder {
+    position: sticky;
+    position: -webkit-sticky;
+    top: 0;
+    height: var(--menu-bar-height);
+}
+#menu-bar.bordered {
+    border-bottom-color: var(--table-border-color);
+}
+#menu-bar i, #menu-bar .icon-button {
+    position: relative;
+    padding: 0 8px;
+    z-index: 10;
+    line-height: var(--menu-bar-height);
+    cursor: pointer;
+    transition: color 0.5s;
+}
+@media only screen and (max-width: 420px) {
+    #menu-bar i, #menu-bar .icon-button {
+        padding: 0 5px;
+    }
+}
+
+.icon-button {
+    border: none;
+    background: none;
+    padding: 0;
+    color: inherit;
+}
+.icon-button i {
+    margin: 0;
+}
+
+.right-buttons {
+    margin: 0 15px;
+}
+.right-buttons a {
+    text-decoration: none;
+}
+
+.left-buttons {
+    display: flex;
+    margin: 0 5px;
+}
+.no-js .left-buttons {
+    display: none;
+}
+
+.menu-title {
+    display: inline-block;
+    font-weight: 200;
+    font-size: 2.4rem;
+    line-height: var(--menu-bar-height);
+    text-align: center;
+    margin: 0;
+    flex: 1;
+    white-space: nowrap;
+    overflow: hidden;
+    text-overflow: ellipsis;
+}
+.js .menu-title {
+    cursor: pointer;
+}
+
+.menu-bar,
+.menu-bar:visited,
+.nav-chapters,
+.nav-chapters:visited,
+.mobile-nav-chapters,
+.mobile-nav-chapters:visited,
+.menu-bar .icon-button,
+.menu-bar a i {
+    color: var(--icons);
+}
+
+.menu-bar i:hover,
+.menu-bar .icon-button:hover,
+.nav-chapters:hover,
+.mobile-nav-chapters i:hover {
+    color: var(--icons-hover);
+}
+
+/* Nav Icons */
+
+.nav-chapters {
+    font-size: 2.5em;
+    text-align: center;
+    text-decoration: none;
+
+    position: fixed;
+    top: 0;
+    bottom: 0;
+    margin: 0;
+    max-width: 150px;
+    min-width: 90px;
+
+    display: flex;
+    justify-content: center;
+    align-content: center;
+    flex-direction: column;
+
+    transition: color 0.5s, background-color 0.5s;
+}
+
+.nav-chapters:hover {
+    text-decoration: none;
+    background-color: var(--theme-hover);
+    transition: background-color 0.15s, color 0.15s;
+}
+
+.nav-wrapper {
+    margin-top: 50px;
+    display: none;
+}
+
+.mobile-nav-chapters {
+    font-size: 2.5em;
+    text-align: center;
+    text-decoration: none;
+    width: 90px;
+    border-radius: 5px;
+    background-color: var(--sidebar-bg);
+}
+
+.previous {
+    float: left;
+}
+
+.next {
+    float: right;
+    right: var(--page-padding);
+}
+
+@media only screen and (max-width: 1080px) {
+    .nav-wide-wrapper { display: none; }
+    .nav-wrapper { display: block; }
+}
+
+@media only screen and (max-width: 1380px) {
+    .sidebar-visible .nav-wide-wrapper { display: none; }
+    .sidebar-visible .nav-wrapper { display: block; }
+}
+
+/* Inline code */
+
+:not(pre) > .hljs {
+    display: inline;
+    padding: 0.1em 0.3em;
+    border-radius: 3px;
+}
+
+:not(pre):not(a) > .hljs {
+    color: var(--inline-code-color);
+    overflow-x: initial;
+}
+
+a:hover > .hljs {
+    text-decoration: underline;
+}
+
+pre {
+    position: relative;
+}
+pre > .buttons {
+    position: absolute;
+    z-index: 100;
+    right: 5px;
+    top: 5px;
+
+    color: var(--sidebar-fg);
+    cursor: pointer;
+}
+pre > .buttons :hover {
+    color: var(--sidebar-active);
+}
+pre > .buttons i {
+    margin-left: 8px;
+}
+pre > .buttons button {
+    color: inherit;
+    background: transparent;
+    border: none;
+    cursor: inherit;
+}
+pre > .result {
+    margin-top: 10px;
+}
+
+/* Search */
+
+#searchresults a {
+    text-decoration: none;
+}
+
+mark {
+    border-radius: 2px;
+    padding: 0 3px 1px 3px;
+    margin: 0 -3px -1px -3px;
+    background-color: var(--search-mark-bg);
+    transition: background-color 300ms linear;
+    cursor: pointer;
+}
+
+mark.fade-out {
+    background-color: rgba(0,0,0,0) !important;
+    cursor: auto;
+}
+
+.searchbar-outer {
+    margin-left: auto;
+    margin-right: auto;
+    max-width: var(--content-max-width);
+}
+
+#searchbar {
+    width: 100%;
+    margin: 5px auto 0px auto;
+    padding: 10px 16px;
+    transition: box-shadow 300ms ease-in-out;
+    border: 1px solid var(--searchbar-border-color);
+    border-radius: 3px;
+    background-color: var(--searchbar-bg);
+    color: var(--searchbar-fg);
+}
+#searchbar:focus,
+#searchbar.active {
+    box-shadow: 0 0 3px var(--searchbar-shadow-color);
+}
+
+.searchresults-header {
+    font-weight: bold;
+    font-size: 1em;
+    padding: 18px 0 0 5px;
+    color: var(--searchresults-header-fg);
+}
+
+.searchresults-outer {
+    margin-left: auto;
+    margin-right: auto;
+    max-width: var(--content-max-width);
+    border-bottom: 1px dashed var(--searchresults-border-color);
+}
+
+ul#searchresults {
+    list-style: none;
+    padding-left: 20px;
+}
+ul#searchresults li {
+    margin: 10px 0px;
+    padding: 2px;
+    border-radius: 2px;
+}
+ul#searchresults li.focus {
+    background-color: var(--searchresults-li-bg);
+}
+ul#searchresults span.teaser {
+    display: block;
+    clear: both;
+    margin: 5px 0 0 20px;
+    font-size: 0.8em;
+}
+ul#searchresults span.teaser em {
+    font-weight: bold;
+    font-style: normal;
+}
+
+/* Sidebar */
+
+.sidebar {
+    position: fixed;
+    left: 0;
+    top: 0;
+    bottom: 0;
+    width: var(--sidebar-width);
+    font-size: 0.875em;
+    box-sizing: border-box;
+    -webkit-overflow-scrolling: touch;
+    overscroll-behavior-y: contain;
+    background-color: var(--sidebar-bg);
+    color: var(--sidebar-fg);
+}
+.sidebar-resizing {
+    -moz-user-select: none;
+    -webkit-user-select: none;
+    -ms-user-select: none;
+    user-select: none;
+}
+.js:not(.sidebar-resizing) .sidebar {
+    transition: transform 0.3s; /* Animation: slide away */
+}
+.sidebar code {
+    line-height: 2em;
+}
+.sidebar .sidebar-scrollbox {
+    overflow-y: auto;
+    position: absolute;
+    top: 0;
+    bottom: 0;
+    left: 0;
+    right: 0;
+    padding: 10px 10px;
+}
+.sidebar .sidebar-resize-handle {
+    position: absolute;
+    cursor: col-resize;
+    width: 0;
+    right: 0;
+    top: 0;
+    bottom: 0;
+}
+.js .sidebar .sidebar-resize-handle {
+    cursor: col-resize;
+    width: 5px;
+}
+.sidebar-hidden .sidebar {
+    transform: translateX(calc(0px - var(--sidebar-width)));
+}
+.sidebar::-webkit-scrollbar {
+    background: var(--sidebar-bg);
+}
+.sidebar::-webkit-scrollbar-thumb {
+    background: var(--scrollbar);
+}
+
+.sidebar-visible .page-wrapper {
+    transform: translateX(var(--sidebar-width));
+}
+@media only screen and (min-width: 620px) {
+    .sidebar-visible .page-wrapper {
+        transform: none;
+        margin-left: var(--sidebar-width);
+    }
+}
+
+.chapter {
+    list-style: none outside none;
+    padding-left: 0;
+    line-height: 2.2em;
+}
+
+.chapter ol {
+    width: 100%;
+}
+
+.chapter li {
+    display: flex;
+    color: var(--sidebar-non-existant);
+}
+.chapter li a {
+    display: block;
+    padding: 0;
+    text-decoration: none;
+    color: var(--sidebar-fg);
+}
+
+.chapter li a:hover {
+    color: var(--sidebar-active);
+}
+
+.chapter li a.active {
+    color: var(--sidebar-active);
+}
+
+.chapter li > a.toggle {
+    cursor: pointer;
+    display: block;
+    margin-left: auto;
+    padding: 0 10px;
+    user-select: none;
+    opacity: 0.68;
+}
+
+.chapter li > a.toggle div {
+    transition: transform 0.5s;
+}
+
+/* collapse the section */
+.chapter li:not(.expanded) + li > ol {
+    display: none;
+}
+
+.chapter li.chapter-item {
+    line-height: 1.5em;
+    margin-top: 0.6em;
+}
+
+.chapter li.expanded > a.toggle div {
+    transform: rotate(90deg);
+}
+
+.spacer {
+    width: 100%;
+    height: 3px;
+    margin: 5px 0px;
+}
+.chapter .spacer {
+    background-color: var(--sidebar-spacer);
+}
+
+@media (-moz-touch-enabled: 1), (pointer: coarse) {
+    .chapter li a { padding: 5px 0; }
+    .spacer { margin: 10px 0; }
+}
+
+.section {
+    list-style: none outside none;
+    padding-left: 20px;
+    line-height: 1.9em;
+}
+
+/* Theme Menu Popup */
+
+.theme-popup {
+    position: absolute;
+    left: 10px;
+    top: var(--menu-bar-height);
+    z-index: 1000;
+    border-radius: 4px;
+    font-size: 0.7em;
+    color: var(--fg);
+    background: var(--theme-popup-bg);
+    border: 1px solid var(--theme-popup-border);
+    margin: 0;
+    padding: 0;
+    list-style: none;
+    display: none;
+}
+.theme-popup .default {
+    color: var(--icons);
+}
+.theme-popup .theme {
+    width: 100%;
+    border: 0;
+    margin: 0;
+    padding: 2px 10px;
+    line-height: 25px;
+    white-space: nowrap;
+    text-align: left;
+    cursor: pointer;
+    color: inherit;
+    background: inherit;
+    font-size: inherit;
+}
+.theme-popup .theme:hover {
+    background-color: var(--theme-hover);
+}
+.theme-popup .theme:hover:first-child,
+.theme-popup .theme:hover:last-child {
+    border-top-left-radius: inherit;
+    border-top-right-radius: inherit;
+}

docs/css/general.css

@@ -0,0 +1,182 @@
+/* Base styles and content styles */
+
+@import 'variables.css';
+
+:root {
+    /* Browser default font-size is 16px, this way 1 rem = 10px */
+    font-size: 62.5%;
+}
+
+html {
+    font-family: "Open Sans", sans-serif;
+    color: var(--fg);
+    background-color: var(--bg);
+    text-size-adjust: none;
+    -webkit-text-size-adjust: none;
+}
+
+body {
+    margin: 0;
+    font-size: 1.6rem;
+    overflow-x: hidden;
+}
+
+code {
+    font-family: "Source Code Pro", Consolas, "Ubuntu Mono", Menlo, "DejaVu Sans Mono", monospace, monospace !important;
+    font-size: 0.875em; /* please adjust the ace font size accordingly in editor.js */
+}
+
+/* Don't change font size in headers. */
+h1 code, h2 code, h3 code, h4 code, h5 code, h6 code {
+    font-size: unset;
+}
+
+.left { float: left; }
+.right { float: right; }
+.boring { opacity: 0.6; }
+.hide-boring .boring { display: none; }
+.hidden { display: none !important; }
+
+h2, h3 { margin-top: 2.5em; }
+h4, h5 { margin-top: 2em; }
+
+.header + .header h3,
+.header + .header h4,
+.header + .header h5 {
+    margin-top: 1em;
+}
+
+h1:target::before,
+h2:target::before,
+h3:target::before,
+h4:target::before,
+h5:target::before,
+h6:target::before {
+    display: inline-block;
+    content: "»";
+    margin-left: -30px;
+    width: 30px;
+}
+
+/* This is broken on Safari as of version 14, but is fixed
+   in Safari Technology Preview 117 which I think will be Safari 14.2.
+   https://bugs.webkit.org/show_bug.cgi?id=218076
+*/
+:target {
+    scroll-margin-top: calc(var(--menu-bar-height) + 0.5em);
+}
+
+.page {
+    outline: 0;
+    padding: 0 var(--page-padding);
+    margin-top: calc(0px - var(--menu-bar-height)); /* Compensate for the #menu-bar-hover-placeholder */
+}
+.page-wrapper {
+    box-sizing: border-box;
+}
+.js:not(.sidebar-resizing) .page-wrapper {
+    transition: margin-left 0.3s ease, transform 0.3s ease; /* Animation: slide away */
+}
+
+.content {
+    overflow-y: auto;
+    padding: 0 15px;
+    padding-bottom: 50px;
+}
+.content main {
+    margin-left: auto;
+    margin-right: auto;
+    max-width: var(--content-max-width);
+}
+.content p { line-height: 1.45em; }
+.content ol { line-height: 1.45em; }
+.content ul { line-height: 1.45em; }
+.content a { text-decoration: none; }
+.content a:hover { text-decoration: underline; }
+.content img, .content video { max-width: 100%; }
+.content .header:link,
+.content .header:visited {
+    color: var(--fg);
+}
+.content .header:link,
+.content .header:visited:hover {
+    text-decoration: none;
+}
+
+table {
+    margin: 0 auto;
+    border-collapse: collapse;
+}
+table td {
+    padding: 3px 20px;
+    border: 1px var(--table-border-color) solid;
+}
+table thead {
+    background: var(--table-header-bg);
+}
+table thead td {
+    font-weight: 700;
+    border: none;
+}
+table thead th {
+    padding: 3px 20px;
+}
+table thead tr {
+    border: 1px var(--table-header-bg) solid;
+}
+/* Alternate background colors for rows */
+table tbody tr:nth-child(2n) {
+    background: var(--table-alternate-bg);
+}
+
+
+blockquote {
+    margin: 20px 0;
+    padding: 0 20px;
+    color: var(--fg);
+    background-color: var(--quote-bg);
+    border-top: .1em solid var(--quote-border);
+    border-bottom: .1em solid var(--quote-border);
+}
+
+
+:not(.footnote-definition) + .footnote-definition,
+.footnote-definition + :not(.footnote-definition) {
+    margin-top: 2em;
+}
+.footnote-definition {
+    font-size: 0.9em;
+    margin: 0.5em 0;
+}
+.footnote-definition p {
+    display: inline;
+}
+
+.tooltiptext {
+    position: absolute;
+    visibility: hidden;
+    color: #fff;
+    background-color: #333;
+    transform: translateX(-50%); /* Center by moving tooltip 50% of its width left */
+    left: -8px; /* Half of the width of the icon */
+    top: -35px;
+    font-size: 0.8em;
+    text-align: center;
+    border-radius: 6px;
+    padding: 5px 8px;
+    margin: 5px;
+    z-index: 1000;
+}
+.tooltipped .tooltiptext {
+    visibility: visible;
+}
+
+.chapter li.part-title {
+    color: var(--sidebar-fg);
+    margin: 5px 0px;
+    font-weight: bold;
+}
+
+.result-no-output {
+    font-style: italic;
+}

docs/css/print.css

@@ -0,0 +1,54 @@
+
+#sidebar,
+#menu-bar,
+.nav-chapters,
+.mobile-nav-chapters {
+    display: none;
+}
+
+#page-wrapper.page-wrapper {
+    transform: none;
+    margin-left: 0px;
+    overflow-y: initial;
+}
+
+#content {
+    max-width: none;
+    margin: 0;
+    padding: 0;
+}
+
+.page {
+    overflow-y: initial;
+}
+
+code {
+    background-color: #666666;
+    border-radius: 5px;
+
+    /* Force background to be printed in Chrome */
+    -webkit-print-color-adjust: exact;
+}
+
+pre > .buttons {
+    z-index: 2;
+}
+
+a, a:visited, a:active, a:hover {
+    color: #4183c4;
+    text-decoration: none;
+}
+
+h1, h2, h3, h4, h5, h6 {
+    page-break-inside: avoid;
+    page-break-after: avoid;
+}
+
+pre, code {
+    page-break-inside: avoid;
+    white-space: pre-wrap;
+}
+
+.fa {
+    display: none !important;
+}

docs/css/variables.css

@@ -0,0 +1,253 @@
+
+/* Globals */
+
+:root {
+    --sidebar-width: 300px;
+    --page-padding: 15px;
+    --content-max-width: 750px;
+    --menu-bar-height: 50px;
+}
+
+/* Themes */
+
+.ayu {
+    --bg: hsl(210, 25%, 8%);
+    --fg: #c5c5c5;
+
+    --sidebar-bg: #14191f;
+    --sidebar-fg: #c8c9db;
+    --sidebar-non-existant: #5c6773;
+    --sidebar-active: #ffb454;
+    --sidebar-spacer: #2d334f;
+
+    --scrollbar: var(--sidebar-fg);
+
+    --icons: #737480;
+    --icons-hover: #b7b9cc;
+
+    --links: #0096cf;
+
+    --inline-code-color: #ffb454;
+
+    --theme-popup-bg: #14191f;
+    --theme-popup-border: #5c6773;
+    --theme-hover: #191f26;
+
+    --quote-bg: hsl(226, 15%, 17%);
+    --quote-border: hsl(226, 15%, 22%);
+
+    --table-border-color: hsl(210, 25%, 13%);
+    --table-header-bg: hsl(210, 25%, 28%);
+    --table-alternate-bg: hsl(210, 25%, 11%);
+
+    --searchbar-border-color: #848484;
+    --searchbar-bg: #424242;
+    --searchbar-fg: #fff;
+    --searchbar-shadow-color: #d4c89f;
+    --searchresults-header-fg: #666;
+    --searchresults-border-color: #888;
+    --searchresults-li-bg: #252932;
+    --search-mark-bg: #e3b171;
+}
+
+.coal {
+    --bg: hsl(200, 7%, 8%);
+    --fg: #98a3ad;
+
+    --sidebar-bg: #292c2f;
+    --sidebar-fg: #a1adb8;
+    --sidebar-non-existant: #505254;
+    --sidebar-active: #3473ad;
+    --sidebar-spacer: #393939;
+
+    --scrollbar: var(--sidebar-fg);
+
+    --icons: #43484d;
+    --icons-hover: #b3c0cc;
+
+    --links: #2b79a2;
+
+    --inline-code-color: #c5c8c6;
+
+    --theme-popup-bg: #141617;
+    --theme-popup-border: #43484d;
+    --theme-hover: #1f2124;
+
+    --quote-bg: hsl(234, 21%, 18%);
+    --quote-border: hsl(234, 21%, 23%);
+
+    --table-border-color: hsl(200, 7%, 13%);
+    --table-header-bg: hsl(200, 7%, 28%);
+    --table-alternate-bg: hsl(200, 7%, 11%);
+
+    --searchbar-border-color: #aaa;
+    --searchbar-bg: #b7b7b7;
+    --searchbar-fg: #000;
+    --searchbar-shadow-color: #aaa;
+    --searchresults-header-fg: #666;
+    --searchresults-border-color: #98a3ad;
+    --searchresults-li-bg: #2b2b2f;
+    --search-mark-bg: #355c7d;
+}
+
+.light {
+    --bg: hsl(0, 0%, 100%);
+    --fg: hsl(0, 0%, 0%);
+
+    --sidebar-bg: #fafafa;
+    --sidebar-fg: hsl(0, 0%, 0%);
+    --sidebar-non-existant: #aaaaaa;
+    --sidebar-active: #1f1fff;
+    --sidebar-spacer: #f4f4f4;
+
+    --scrollbar: #8F8F8F;
+
+    --icons: #747474;
+    --icons-hover: #000000;
+
+    --links: #20609f;
+
+    --inline-code-color: #301900;
+
+    --theme-popup-bg: #fafafa;
+    --theme-popup-border: #cccccc;
+    --theme-hover: #e6e6e6;
+
+    --quote-bg: hsl(197, 37%, 96%);
+    --quote-border: hsl(197, 37%, 91%);
+
+    --table-border-color: hsl(0, 0%, 95%);
+    --table-header-bg: hsl(0, 0%, 80%);
+    --table-alternate-bg: hsl(0, 0%, 97%);
+
+    --searchbar-border-color: #aaa;
+    --searchbar-bg: #fafafa;
+    --searchbar-fg: #000;
+    --searchbar-shadow-color: #aaa;
+    --searchresults-header-fg: #666;
+    --searchresults-border-color: #888;
+    --searchresults-li-bg: #e4f2fe;
+    --search-mark-bg: #a2cff5;
+}
+
+.navy {
+    --bg: hsl(226, 23%, 11%);
+    --fg: #bcbdd0;
+
+    --sidebar-bg: #282d3f;
+    --sidebar-fg: #c8c9db;
+    --sidebar-non-existant: #505274;
+    --sidebar-active: #2b79a2;
+    --sidebar-spacer: #2d334f;
+
+    --scrollbar: var(--sidebar-fg);
+
+    --icons: #737480;
+    --icons-hover: #b7b9cc;
+
+    --links: #2b79a2;
+
+    --inline-code-color: #c5c8c6;
+
+    --theme-popup-bg: #161923;
+    --theme-popup-border: #737480;
+    --theme-hover: #282e40;
+
+    --quote-bg: hsl(226, 15%, 17%);
+    --quote-border: hsl(226, 15%, 22%);
+
+    --table-border-color: hsl(226, 23%, 16%);
+    --table-header-bg: hsl(226, 23%, 31%);
+    --table-alternate-bg: hsl(226, 23%, 14%);
+
+    --searchbar-border-color: #aaa;
+    --searchbar-bg: #aeaec6;
+    --searchbar-fg: #000;
+    --searchbar-shadow-color: #aaa;
+    --searchresults-header-fg: #5f5f71;
+    --searchresults-border-color: #5c5c68;
+    --searchresults-li-bg: #242430;
+    --search-mark-bg: #a2cff5;
+}
+
+.rust {
+    --bg: hsl(60, 9%, 87%);
+    --fg: #262625;
+
+    --sidebar-bg: #3b2e2a;
+    --sidebar-fg: #c8c9db;
+    --sidebar-non-existant: #505254;
+    --sidebar-active: #e69f67;
+    --sidebar-spacer: #45373a;
+
+    --scrollbar: var(--sidebar-fg);
+
+    --icons: #737480;
+    --icons-hover: #262625;
+
+    --links: #2b79a2;
+
+    --inline-code-color: #6e6b5e;
+
+    --theme-popup-bg: #e1e1db;
+    --theme-popup-border: #b38f6b;
+    --theme-hover: #99908a;
+
+    --quote-bg: hsl(60, 5%, 75%);
+    --quote-border: hsl(60, 5%, 70%);
+
+    --table-border-color: hsl(60, 9%, 82%);
+    --table-header-bg: #b3a497;
+    --table-alternate-bg: hsl(60, 9%, 84%);
+
+    --searchbar-border-color: #aaa;
+    --searchbar-bg: #fafafa;
+    --searchbar-fg: #000;
+    --searchbar-shadow-color: #aaa;
+    --searchresults-header-fg: #666;
+    --searchresults-border-color: #888;
+    --searchresults-li-bg: #dec2a2;
+    --search-mark-bg: #e69f67;
+}
+
+@media (prefers-color-scheme: dark) {
+    .light.no-js {
+        --bg: hsl(200, 7%, 8%);
+        --fg: #98a3ad;
+
+        --sidebar-bg: #292c2f;
+        --sidebar-fg: #a1adb8;
+        --sidebar-non-existant: #505254;
+        --sidebar-active: #3473ad;
+        --sidebar-spacer: #393939;
+
+        --scrollbar: var(--sidebar-fg);
+
+        --icons: #43484d;
+        --icons-hover: #b3c0cc;
+
+        --links: #2b79a2;
+
+        --inline-code-color: #c5c8c6;
+
+        --theme-popup-bg: #141617;
+        --theme-popup-border: #43484d;
+        --theme-hover: #1f2124;
+
+        --quote-bg: hsl(234, 21%, 18%);
+        --quote-border: hsl(234, 21%, 23%);
+
+        --table-border-color: hsl(200, 7%, 13%);
+        --table-header-bg: hsl(200, 7%, 28%);
+        --table-alternate-bg: hsl(200, 7%, 11%);
+
+        --searchbar-border-color: #aaa;
+        --searchbar-bg: #b7b7b7;
+        --searchbar-fg: #000;
+        --searchbar-shadow-color: #aaa;
+        --searchresults-header-fg: #666;
+        --searchresults-border-color: #98a3ad;
+        --searchresults-li-bg: #2b2b2f;
+        --search-mark-bg: #355c7d;
+    }
+}

docs/favicon.svg

@@ -0,0 +1,22 @@
+<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 199.7 184.2">
+  <style>
+    @media (prefers-color-scheme: dark) {
+      svg { fill: white; }
+    }
+  </style>
+<path d="M189.5,36.8c0.2,2.8,0,5.1-0.6,6.8L153,162c-0.6,2.1-2,3.7-4.2,5c-2.2,1.2-4.4,1.9-6.7,1.9H31.4c-9.6,0-15.3-2.8-17.3-8.4
+  c-0.8-2.2-0.8-3.9,0.1-5.2c0.9-1.2,2.4-1.8,4.6-1.8H123c7.4,0,12.6-1.4,15.4-4.1s5.7-8.9,8.6-18.4l32.9-108.6
+  c1.8-5.9,1-11.1-2.2-15.6S169.9,0,164,0H72.7c-1,0-3.1,0.4-6.1,1.1l0.1-0.4C64.5,0.2,62.6,0,61,0.1s-3,0.5-4.3,1.4
+  c-1.3,0.9-2.4,1.8-3.2,2.8S52,6.5,51.2,8.1c-0.8,1.6-1.4,3-1.9,4.3s-1.1,2.7-1.8,4.2c-0.7,1.5-1.3,2.7-2,3.7c-0.5,0.6-1.2,1.5-2,2.5
+  s-1.6,2-2.2,2.8s-0.9,1.5-1.1,2.2c-0.2,0.7-0.1,1.8,0.2,3.2c0.3,1.4,0.4,2.4,0.4,3.1c-0.3,3-1.4,6.9-3.3,11.6
+  c-1.9,4.7-3.6,8.1-5.1,10.1c-0.3,0.4-1.2,1.3-2.6,2.7c-1.4,1.4-2.3,2.6-2.6,3.7c-0.3,0.4-0.3,1.5-0.1,3.4c0.3,1.8,0.4,3.1,0.3,3.8
+  c-0.3,2.7-1.3,6.3-3,10.8c-1.7,4.5-3.4,8.2-5,11c-0.2,0.5-0.9,1.4-2,2.8c-1.1,1.4-1.8,2.5-2,3.4c-0.2,0.6-0.1,1.8,0.1,3.4
+  c0.2,1.6,0.2,2.8-0.1,3.6c-0.6,3-1.8,6.7-3.6,11c-1.8,4.3-3.6,7.9-5.4,11c-0.5,0.8-1.1,1.7-2,2.8c-0.8,1.1-1.5,2-2,2.8
+  s-0.8,1.6-1,2.5c-0.1,0.5,0,1.3,0.4,2.3c0.3,1.1,0.4,1.9,0.4,2.6c-0.1,1.1-0.2,2.6-0.5,4.4c-0.2,1.8-0.4,2.9-0.4,3.2
+  c-1.8,4.8-1.7,9.9,0.2,15.2c2.2,6.2,6.2,11.5,11.9,15.8c5.7,4.3,11.7,6.4,17.8,6.4h110.7c5.2,0,10.1-1.7,14.7-5.2s7.7-7.8,9.2-12.9
+  l33-108.6c1.8-5.8,1-10.9-2.2-15.5C194.9,39.7,192.6,38,189.5,36.8z M59.6,122.8L73.8,80c0,0,7,0,10.8,0s28.8-1.7,25.4,17.5
+  c-3.4,19.2-18.8,25.2-36.8,25.4S59.6,122.8,59.6,122.8z M78.6,116.8c4.7-0.1,18.9-2.9,22.1-17.1S89.2,86.3,89.2,86.3l-8.9,0
+  l-10.2,30.5C70.2,116.9,74,116.9,78.6,116.8z M75.3,68.7L89,26.2h9.8l0.8,34l23.6-34h9.9l-13.6,42.5h-7.1l12.5-35.4l-24.5,35.4h-6.8
+  l-0.8-35L82,68.7H75.3z"/>
+</svg>
+<!-- Original image Copyright Dave Gandy — CC BY 4.0 License -->

docs/fonts/OPEN-SANS-LICENSE.txt

@@ -0,0 +1,202 @@
+
+                                 Apache License
+                           Version 2.0, January 2004
+                        http://www.apache.org/licenses/
+
+   TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
+
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+   See the License for the specific language governing permissions and
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docs/fonts/SOURCE-CODE-PRO-LICENSE.txt

@@ -0,0 +1,93 @@
+Copyright 2010, 2012 Adobe Systems Incorporated (http://www.adobe.com/), with Reserved Font Name 'Source'. All Rights Reserved. Source is a trademark of Adobe Systems Incorporated in the United States and/or other countries.
+
+This Font Software is licensed under the SIL Open Font License, Version 1.1.
+This license is copied below, and is also available with a FAQ at:
+http://scripts.sil.org/OFL
+
+
+-----------------------------------------------------------
+SIL OPEN FONT LICENSE Version 1.1 - 26 February 2007
+-----------------------------------------------------------
+
+PREAMBLE
+The goals of the Open Font License (OFL) are to stimulate worldwide
+development of collaborative font projects, to support the font creation
+efforts of academic and linguistic communities, and to provide a free and
+open framework in which fonts may be shared and improved in partnership
+with others.
+
+The OFL allows the licensed fonts to be used, studied, modified and
+redistributed freely as long as they are not sold by themselves. The
+fonts, including any derivative works, can be bundled, embedded, 
+redistributed and/or sold with any software provided that any reserved
+names are not used by derivative works. The fonts and derivatives,
+however, cannot be released under any other type of license. The
+requirement for fonts to remain under this license does not apply
+to any document created using the fonts or their derivatives.
+
+DEFINITIONS
+"Font Software" refers to the set of files released by the Copyright
+Holder(s) under this license and clearly marked as such. This may
+include source files, build scripts and documentation.
+
+"Reserved Font Name" refers to any names specified as such after the
+copyright statement(s).
+
+"Original Version" refers to the collection of Font Software components as
+distributed by the Copyright Holder(s).
+
+"Modified Version" refers to any derivative made by adding to, deleting,
+or substituting -- in part or in whole -- any of the components of the
+Original Version, by changing formats or by porting the Font Software to a
+new environment.
+
+"Author" refers to any designer, engineer, programmer, technical
+writer or other person who contributed to the Font Software.
+
+PERMISSION & CONDITIONS
+Permission is hereby granted, free of charge, to any person obtaining
+a copy of the Font Software, to use, study, copy, merge, embed, modify,
+redistribute, and sell modified and unmodified copies of the Font
+Software, subject to the following conditions:
+
+1) Neither the Font Software nor any of its individual components,
+in Original or Modified Versions, may be sold by itself.
+
+2) Original or Modified Versions of the Font Software may be bundled,
+redistributed and/or sold with any software, provided that each copy
+contains the above copyright notice and this license. These can be
+included either as stand-alone text files, human-readable headers or
+in the appropriate machine-readable metadata fields within text or
+binary files as long as those fields can be easily viewed by the user.
+
+3) No Modified Version of the Font Software may use the Reserved Font
+Name(s) unless explicit written permission is granted by the corresponding
+Copyright Holder. This restriction only applies to the primary font name as
+presented to the users.
+
+4) The name(s) of the Copyright Holder(s) or the Author(s) of the Font
+Software shall not be used to promote, endorse or advertise any
+Modified Version, except to acknowledge the contribution(s) of the
+Copyright Holder(s) and the Author(s) or with their explicit written
+permission.
+
+5) The Font Software, modified or unmodified, in part or in whole,
+must be distributed entirely under this license, and must not be
+distributed under any other license. The requirement for fonts to
+remain under this license does not apply to any document created
+using the Font Software.
+
+TERMINATION
+This license becomes null and void if any of the above conditions are
+not met.
+
+DISCLAIMER
+THE FONT SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO ANY WARRANTIES OF
+MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT
+OF COPYRIGHT, PATENT, TRADEMARK, OR OTHER RIGHT. IN NO EVENT SHALL THE
+COPYRIGHT HOLDER BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
+INCLUDING ANY GENERAL, SPECIAL, INDIRECT, INCIDENTAL, OR CONSEQUENTIAL
+DAMAGES, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+FROM, OUT OF THE USE OR INABILITY TO USE THE FONT SOFTWARE OR FROM
+OTHER DEALINGS IN THE FONT SOFTWARE.

docs/fonts/fonts.css

@@ -0,0 +1,100 @@
+/* Open Sans is licensed under the Apache License, Version 2.0. See http://www.apache.org/licenses/LICENSE-2.0 */
+/* Source Code Pro is under the Open Font License. See https://scripts.sil.org/cms/scripts/page.php?site_id=nrsi&id=OFL */
+
+/* open-sans-300 - latin_vietnamese_latin-ext_greek-ext_greek_cyrillic-ext_cyrillic */
+@font-face {
+  font-family: 'Open Sans';
+  font-style: normal;
+  font-weight: 300;
+  src: local('Open Sans Light'), local('OpenSans-Light'),
+       url('open-sans-v17-all-charsets-300.woff2') format('woff2');
+}
+
+/* open-sans-300italic - latin_vietnamese_latin-ext_greek-ext_greek_cyrillic-ext_cyrillic */
+@font-face {
+  font-family: 'Open Sans';
+  font-style: italic;
+  font-weight: 300;
+  src: local('Open Sans Light Italic'), local('OpenSans-LightItalic'),
+       url('open-sans-v17-all-charsets-300italic.woff2') format('woff2');
+}
+
+/* open-sans-regular - latin_vietnamese_latin-ext_greek-ext_greek_cyrillic-ext_cyrillic */
+@font-face {
+  font-family: 'Open Sans';
+  font-style: normal;
+  font-weight: 400;
+  src: local('Open Sans Regular'), local('OpenSans-Regular'),
+       url('open-sans-v17-all-charsets-regular.woff2') format('woff2');
+}
+
+/* open-sans-italic - latin_vietnamese_latin-ext_greek-ext_greek_cyrillic-ext_cyrillic */
+@font-face {
+  font-family: 'Open Sans';
+  font-style: italic;
+  font-weight: 400;
+  src: local('Open Sans Italic'), local('OpenSans-Italic'),
+       url('open-sans-v17-all-charsets-italic.woff2') format('woff2');
+}
+
+/* open-sans-600 - latin_vietnamese_latin-ext_greek-ext_greek_cyrillic-ext_cyrillic */
+@font-face {
+  font-family: 'Open Sans';
+  font-style: normal;
+  font-weight: 600;
+  src: local('Open Sans SemiBold'), local('OpenSans-SemiBold'),
+       url('open-sans-v17-all-charsets-600.woff2') format('woff2');
+}
+
+/* open-sans-600italic - latin_vietnamese_latin-ext_greek-ext_greek_cyrillic-ext_cyrillic */
+@font-face {
+  font-family: 'Open Sans';
+  font-style: italic;
+  font-weight: 600;
+  src: local('Open Sans SemiBold Italic'), local('OpenSans-SemiBoldItalic'),
+       url('open-sans-v17-all-charsets-600italic.woff2') format('woff2');
+}
+
+/* open-sans-700 - latin_vietnamese_latin-ext_greek-ext_greek_cyrillic-ext_cyrillic */
+@font-face {
+  font-family: 'Open Sans';
+  font-style: normal;
+  font-weight: 700;
+  src: local('Open Sans Bold'), local('OpenSans-Bold'),
+       url('open-sans-v17-all-charsets-700.woff2') format('woff2');
+}
+
+/* open-sans-700italic - latin_vietnamese_latin-ext_greek-ext_greek_cyrillic-ext_cyrillic */
+@font-face {
+  font-family: 'Open Sans';
+  font-style: italic;
+  font-weight: 700;
+  src: local('Open Sans Bold Italic'), local('OpenSans-BoldItalic'),
+       url('open-sans-v17-all-charsets-700italic.woff2') format('woff2');
+}
+
+/* open-sans-800 - latin_vietnamese_latin-ext_greek-ext_greek_cyrillic-ext_cyrillic */
+@font-face {
+  font-family: 'Open Sans';
+  font-style: normal;
+  font-weight: 800;
+  src: local('Open Sans ExtraBold'), local('OpenSans-ExtraBold'),
+       url('open-sans-v17-all-charsets-800.woff2') format('woff2');
+}
+
+/* open-sans-800italic - latin_vietnamese_latin-ext_greek-ext_greek_cyrillic-ext_cyrillic */
+@font-face {
+  font-family: 'Open Sans';
+  font-style: italic;
+  font-weight: 800;
+  src: local('Open Sans ExtraBold Italic'), local('OpenSans-ExtraBoldItalic'),
+       url('open-sans-v17-all-charsets-800italic.woff2') format('woff2');
+}
+
+/* source-code-pro-500 - latin_vietnamese_latin-ext_greek_cyrillic-ext_cyrillic */
+@font-face {
+  font-family: 'Source Code Pro';
+  font-style: normal;
+  font-weight: 500;
+  src: url('source-code-pro-v11-all-charsets-500.woff2') format('woff2');
+}

docs/highlight.css

@@ -0,0 +1,83 @@
+/*
+ * An increased contrast highlighting scheme loosely based on the
+ * "Base16 Atelier Dune Light" theme by Bram de Haan
+ * (http://atelierbram.github.io/syntax-highlighting/atelier-schemes/dune)
+ * Original Base16 color scheme by Chris Kempson
+ * (https://github.com/chriskempson/base16)
+ */
+
+/* Comment */
+.hljs-comment,
+.hljs-quote {
+  color: #575757;
+}
+
+/* Red */
+.hljs-variable,
+.hljs-template-variable,
+.hljs-attribute,
+.hljs-tag,
+.hljs-name,
+.hljs-regexp,
+.hljs-link,
+.hljs-name,
+.hljs-selector-id,
+.hljs-selector-class {
+  color: #d70025;
+}
+
+/* Orange */
+.hljs-number,
+.hljs-meta,
+.hljs-built_in,
+.hljs-builtin-name,
+.hljs-literal,
+.hljs-type,
+.hljs-params {
+  color: #b21e00;
+}
+
+/* Green */
+.hljs-string,
+.hljs-symbol,
+.hljs-bullet {
+  color: #008200;
+}
+
+/* Blue */
+.hljs-title,
+.hljs-section {
+  color: #0030f2;
+}
+
+/* Purple */
+.hljs-keyword,
+.hljs-selector-tag {
+  color: #9d00ec;
+}
+
+.hljs {
+  display: block;
+  overflow-x: auto;
+  background: #f6f7f6;
+  color: #000;
+  padding: 0.5em;
+}
+
+.hljs-emphasis {
+  font-style: italic;
+}
+
+.hljs-strong {
+  font-weight: bold;
+}
+
+.hljs-addition {
+  color: #22863a;
+  background-color: #f0fff4;
+}
+
+.hljs-deletion {
+  color: #b31d28;
+  background-color: #ffeef0;
+}

docs/index.html

@@ -0,0 +1,171 @@
+<!DOCTYPE HTML>
+<html lang="en" class="sidebar-visible no-js light">
+    <head>
+        <!-- Book generated using mdBook -->
+        <meta charset="UTF-8">
+        <title>Introduction - Birb2D</title>
+        <!-- Custom HTML head -->
+        <meta content="text/html; charset=utf-8" http-equiv="Content-Type">
+        <meta name="description" content="">
+        <meta name="viewport" content="width=device-width, initial-scale=1">
+        <meta name="theme-color" content="#ffffff" />
+
+        <link rel="icon" href="favicon.svg">
+        <link rel="shortcut icon" href="favicon.png">
+        <link rel="stylesheet" href="css/variables.css">
+        <link rel="stylesheet" href="css/general.css">
+        <link rel="stylesheet" href="css/chrome.css">
+        <link rel="stylesheet" href="css/print.css" media="print">
+        <!-- Fonts -->
+        <link rel="stylesheet" href="FontAwesome/css/font-awesome.css">
+        <link rel="stylesheet" href="fonts/fonts.css">
+        <!-- Highlight.js Stylesheets -->
+        <link rel="stylesheet" href="highlight.css">
+        <link rel="stylesheet" href="tomorrow-night.css">
+        <link rel="stylesheet" href="ayu-highlight.css">
+
+        <!-- Custom theme stylesheets -->
+    </head>
+    <body>
+        <!-- Provide site root to javascript -->
+        <script type="text/javascript">
+            var path_to_root = "";
+            var default_theme = window.matchMedia("(prefers-color-scheme: dark)").matches ? "navy" : "light";
+        </script>
+
+        <!-- Work around some values being stored in localStorage wrapped in quotes -->
+        <script type="text/javascript">
+            try {
+                var theme = localStorage.getItem('mdbook-theme');
+                var sidebar = localStorage.getItem('mdbook-sidebar');
+
+                if (theme.startsWith('"') && theme.endsWith('"')) {
+                    localStorage.setItem('mdbook-theme', theme.slice(1, theme.length - 1));
+                }
+
+                if (sidebar.startsWith('"') && sidebar.endsWith('"')) {
+                    localStorage.setItem('mdbook-sidebar', sidebar.slice(1, sidebar.length - 1));
+                }
+            } catch (e) { }
+        </script>
+
+        <!-- Set the theme before any content is loaded, prevents flash -->
+        <script type="text/javascript">
+            var theme;
+            try { theme = localStorage.getItem('mdbook-theme'); } catch(e) { }
+            if (theme === null || theme === undefined) { theme = default_theme; }
+            var html = document.querySelector('html');
+            html.classList.remove('no-js')
+            html.classList.remove('light')
+            html.classList.add(theme);
+            html.classList.add('js');
+        </script>
+
+        <!-- Hide / unhide sidebar before it is displayed -->
+        <script type="text/javascript">
+            var html = document.querySelector('html');
+            var sidebar = 'hidden';
+            if (document.body.clientWidth >= 1080) {
+                try { sidebar = localStorage.getItem('mdbook-sidebar'); } catch(e) { }
+                sidebar = sidebar || 'visible';
+            }
+            html.classList.remove('sidebar-visible');
+            html.classList.add("sidebar-" + sidebar);
+        </script>
+
+        <nav id="sidebar" class="sidebar" aria-label="Table of contents">
+            <div class="sidebar-scrollbox">
+                <ol class="chapter"><li class="chapter-item expanded "><a href="introduction.html"><strong aria-hidden="true">1.</strong> Introduction</a></li><li class="chapter-item expanded "><a href="rendering.html"><strong aria-hidden="true">2.</strong> Rendering</a></li></ol>
+            </div>
+            <div id="sidebar-resize-handle" class="sidebar-resize-handle"></div>
+        </nav>
+
+        <div id="page-wrapper" class="page-wrapper">
+
+            <div class="page">
+                <div id="menu-bar-hover-placeholder"></div>
+                <div id="menu-bar" class="menu-bar sticky bordered">
+                    <div class="left-buttons">
+                        <button id="sidebar-toggle" class="icon-button" type="button" title="Toggle Table of Contents" aria-label="Toggle Table of Contents" aria-controls="sidebar">
+                            <i class="fa fa-bars"></i>
+                        </button>
+                        <button id="theme-toggle" class="icon-button" type="button" title="Change theme" aria-label="Change theme" aria-haspopup="true" aria-expanded="false" aria-controls="theme-list">
+                            <i class="fa fa-paint-brush"></i>
+                        </button>
+                        <ul id="theme-list" class="theme-popup" aria-label="Themes" role="menu">
+                            <li role="none"><button role="menuitem" class="theme" id="light">Light (default)</button></li>
+                            <li role="none"><button role="menuitem" class="theme" id="rust">Rust</button></li>
+                            <li role="none"><button role="menuitem" class="theme" id="coal">Coal</button></li>
+                            <li role="none"><button role="menuitem" class="theme" id="navy">Navy</button></li>
+                            <li role="none"><button role="menuitem" class="theme" id="ayu">Ayu</button></li>
+                        </ul>
+                        <button id="search-toggle" class="icon-button" type="button" title="Search. (Shortkey: s)" aria-label="Toggle Searchbar" aria-expanded="false" aria-keyshortcuts="S" aria-controls="searchbar">
+                            <i class="fa fa-search"></i>
+                        </button>
+                    </div>
+
+                    <h1 class="menu-title">Birb2D</h1>
+
+                    <div class="right-buttons">
+                        <a href="print.html" title="Print this book" aria-label="Print this book">
+                            <i id="print-button" class="fa fa-print"></i>
+                        </a>
+                    </div>
+                </div>
+
+                <div id="search-wrapper" class="hidden">
+                    <form id="searchbar-outer" class="searchbar-outer">
+                        <input type="search" id="searchbar" name="searchbar" placeholder="Search this book ..." aria-controls="searchresults-outer" aria-describedby="searchresults-header">
+                    </form>
+                    <div id="searchresults-outer" class="searchresults-outer hidden">
+                        <div id="searchresults-header" class="searchresults-header"></div>
+                        <ul id="searchresults">
+                        </ul>
+                    </div>
+                </div>
+                <!-- Apply ARIA attributes after the sidebar and the sidebar toggle button are added to the DOM -->
+                <script type="text/javascript">
+                    document.getElementById('sidebar-toggle').setAttribute('aria-expanded', sidebar === 'visible');
+                    document.getElementById('sidebar').setAttribute('aria-hidden', sidebar !== 'visible');
+                    Array.from(document.querySelectorAll('#sidebar a')).forEach(function(link) {
+                        link.setAttribute('tabIndex', sidebar === 'visible' ? 0 : -1);
+                    });
+                </script>
+
+                <div id="content" class="content">
+                    <main>
+                        <h1 id="introduction"><a class="header" href="#introduction">Introduction</a></h1>
+
+                    </main>
+
+                    <nav class="nav-wrapper" aria-label="Page navigation">
+                        <!-- Mobile navigation buttons -->
+                            <a rel="next" href="rendering.html" class="mobile-nav-chapters next" title="Next chapter" aria-label="Next chapter" aria-keyshortcuts="Right">
+                                <i class="fa fa-angle-right"></i>
+                            </a>
+                        <div style="clear: both"></div>
+                    </nav>
+                </div>
+            </div>
+
+            <nav class="nav-wide-wrapper" aria-label="Page navigation">
+                    <a rel="next" href="rendering.html" class="nav-chapters next" title="Next chapter" aria-label="Next chapter" aria-keyshortcuts="Right">
+                        <i class="fa fa-angle-right"></i>
+                    </a>
+            </nav>
+
+        </div>
+
+        <script type="text/javascript">
+            window.playground_copyable = true;
+        </script>
+        <script src="elasticlunr.min.js" type="text/javascript" charset="utf-8"></script>
+        <script src="mark.min.js" type="text/javascript" charset="utf-8"></script>
+        <script src="searcher.js" type="text/javascript" charset="utf-8"></script>
+        <script src="clipboard.min.js" type="text/javascript" charset="utf-8"></script>
+        <script src="highlight.js" type="text/javascript" charset="utf-8"></script>
+        <script src="book.js" type="text/javascript" charset="utf-8"></script>
+
+        <!-- Custom JS scripts -->
+    </body>
+</html>

docs/introduction.html

@@ -0,0 +1,171 @@
+<!DOCTYPE HTML>
+<html lang="en" class="sidebar-visible no-js light">
+    <head>
+        <!-- Book generated using mdBook -->
+        <meta charset="UTF-8">
+        <title>Introduction - Birb2D</title>
+        <!-- Custom HTML head -->
+        <meta content="text/html; charset=utf-8" http-equiv="Content-Type">
+        <meta name="description" content="">
+        <meta name="viewport" content="width=device-width, initial-scale=1">
+        <meta name="theme-color" content="#ffffff" />
+
+        <link rel="icon" href="favicon.svg">
+        <link rel="shortcut icon" href="favicon.png">
+        <link rel="stylesheet" href="css/variables.css">
+        <link rel="stylesheet" href="css/general.css">
+        <link rel="stylesheet" href="css/chrome.css">
+        <link rel="stylesheet" href="css/print.css" media="print">
+        <!-- Fonts -->
+        <link rel="stylesheet" href="FontAwesome/css/font-awesome.css">
+        <link rel="stylesheet" href="fonts/fonts.css">
+        <!-- Highlight.js Stylesheets -->
+        <link rel="stylesheet" href="highlight.css">
+        <link rel="stylesheet" href="tomorrow-night.css">
+        <link rel="stylesheet" href="ayu-highlight.css">
+
+        <!-- Custom theme stylesheets -->
+    </head>
+    <body>
+        <!-- Provide site root to javascript -->
+        <script type="text/javascript">
+            var path_to_root = "";
+            var default_theme = window.matchMedia("(prefers-color-scheme: dark)").matches ? "navy" : "light";
+        </script>
+
+        <!-- Work around some values being stored in localStorage wrapped in quotes -->
+        <script type="text/javascript">
+            try {
+                var theme = localStorage.getItem('mdbook-theme');
+                var sidebar = localStorage.getItem('mdbook-sidebar');
+
+                if (theme.startsWith('"') && theme.endsWith('"')) {
+                    localStorage.setItem('mdbook-theme', theme.slice(1, theme.length - 1));
+                }
+
+                if (sidebar.startsWith('"') && sidebar.endsWith('"')) {
+                    localStorage.setItem('mdbook-sidebar', sidebar.slice(1, sidebar.length - 1));
+                }
+            } catch (e) { }
+        </script>
+
+        <!-- Set the theme before any content is loaded, prevents flash -->
+        <script type="text/javascript">
+            var theme;
+            try { theme = localStorage.getItem('mdbook-theme'); } catch(e) { }
+            if (theme === null || theme === undefined) { theme = default_theme; }
+            var html = document.querySelector('html');
+            html.classList.remove('no-js')
+            html.classList.remove('light')
+            html.classList.add(theme);
+            html.classList.add('js');
+        </script>
+
+        <!-- Hide / unhide sidebar before it is displayed -->
+        <script type="text/javascript">
+            var html = document.querySelector('html');
+            var sidebar = 'hidden';
+            if (document.body.clientWidth >= 1080) {
+                try { sidebar = localStorage.getItem('mdbook-sidebar'); } catch(e) { }
+                sidebar = sidebar || 'visible';
+            }
+            html.classList.remove('sidebar-visible');
+            html.classList.add("sidebar-" + sidebar);
+        </script>
+
+        <nav id="sidebar" class="sidebar" aria-label="Table of contents">
+            <div class="sidebar-scrollbox">
+                <ol class="chapter"><li class="chapter-item expanded "><a href="introduction.html" class="active"><strong aria-hidden="true">1.</strong> Introduction</a></li><li class="chapter-item expanded "><a href="rendering.html"><strong aria-hidden="true">2.</strong> Rendering</a></li></ol>
+            </div>
+            <div id="sidebar-resize-handle" class="sidebar-resize-handle"></div>
+        </nav>
+
+        <div id="page-wrapper" class="page-wrapper">
+
+            <div class="page">
+                <div id="menu-bar-hover-placeholder"></div>
+                <div id="menu-bar" class="menu-bar sticky bordered">
+                    <div class="left-buttons">
+                        <button id="sidebar-toggle" class="icon-button" type="button" title="Toggle Table of Contents" aria-label="Toggle Table of Contents" aria-controls="sidebar">
+                            <i class="fa fa-bars"></i>
+                        </button>
+                        <button id="theme-toggle" class="icon-button" type="button" title="Change theme" aria-label="Change theme" aria-haspopup="true" aria-expanded="false" aria-controls="theme-list">
+                            <i class="fa fa-paint-brush"></i>
+                        </button>
+                        <ul id="theme-list" class="theme-popup" aria-label="Themes" role="menu">
+                            <li role="none"><button role="menuitem" class="theme" id="light">Light (default)</button></li>
+                            <li role="none"><button role="menuitem" class="theme" id="rust">Rust</button></li>
+                            <li role="none"><button role="menuitem" class="theme" id="coal">Coal</button></li>
+                            <li role="none"><button role="menuitem" class="theme" id="navy">Navy</button></li>
+                            <li role="none"><button role="menuitem" class="theme" id="ayu">Ayu</button></li>
+                        </ul>
+                        <button id="search-toggle" class="icon-button" type="button" title="Search. (Shortkey: s)" aria-label="Toggle Searchbar" aria-expanded="false" aria-keyshortcuts="S" aria-controls="searchbar">
+                            <i class="fa fa-search"></i>
+                        </button>
+                    </div>
+
+                    <h1 class="menu-title">Birb2D</h1>
+
+                    <div class="right-buttons">
+                        <a href="print.html" title="Print this book" aria-label="Print this book">
+                            <i id="print-button" class="fa fa-print"></i>
+                        </a>
+                    </div>
+                </div>
+
+                <div id="search-wrapper" class="hidden">
+                    <form id="searchbar-outer" class="searchbar-outer">
+                        <input type="search" id="searchbar" name="searchbar" placeholder="Search this book ..." aria-controls="searchresults-outer" aria-describedby="searchresults-header">
+                    </form>
+                    <div id="searchresults-outer" class="searchresults-outer hidden">
+                        <div id="searchresults-header" class="searchresults-header"></div>
+                        <ul id="searchresults">
+                        </ul>
+                    </div>
+                </div>
+                <!-- Apply ARIA attributes after the sidebar and the sidebar toggle button are added to the DOM -->
+                <script type="text/javascript">
+                    document.getElementById('sidebar-toggle').setAttribute('aria-expanded', sidebar === 'visible');
+                    document.getElementById('sidebar').setAttribute('aria-hidden', sidebar !== 'visible');
+                    Array.from(document.querySelectorAll('#sidebar a')).forEach(function(link) {
+                        link.setAttribute('tabIndex', sidebar === 'visible' ? 0 : -1);
+                    });
+                </script>
+
+                <div id="content" class="content">
+                    <main>
+                        <h1 id="introduction"><a class="header" href="#introduction">Introduction</a></h1>
+
+                    </main>
+
+                    <nav class="nav-wrapper" aria-label="Page navigation">
+                        <!-- Mobile navigation buttons -->
+                            <a rel="next" href="rendering.html" class="mobile-nav-chapters next" title="Next chapter" aria-label="Next chapter" aria-keyshortcuts="Right">
+                                <i class="fa fa-angle-right"></i>
+                            </a>
+                        <div style="clear: both"></div>
+                    </nav>
+                </div>
+            </div>
+
+            <nav class="nav-wide-wrapper" aria-label="Page navigation">
+                    <a rel="next" href="rendering.html" class="nav-chapters next" title="Next chapter" aria-label="Next chapter" aria-keyshortcuts="Right">
+                        <i class="fa fa-angle-right"></i>
+                    </a>
+            </nav>
+
+        </div>
+
+        <script type="text/javascript">
+            window.playground_copyable = true;
+        </script>
+        <script src="elasticlunr.min.js" type="text/javascript" charset="utf-8"></script>
+        <script src="mark.min.js" type="text/javascript" charset="utf-8"></script>
+        <script src="searcher.js" type="text/javascript" charset="utf-8"></script>
+        <script src="clipboard.min.js" type="text/javascript" charset="utf-8"></script>
+        <script src="highlight.js" type="text/javascript" charset="utf-8"></script>
+        <script src="book.js" type="text/javascript" charset="utf-8"></script>
+
+        <!-- Custom JS scripts -->
+    </body>
+</html>

docs/print.html

@@ -0,0 +1,171 @@
+<!DOCTYPE HTML>
+<html lang="en" class="sidebar-visible no-js light">
+    <head>
+        <!-- Book generated using mdBook -->
+        <meta charset="UTF-8">
+        <title>Birb2D</title>
+        <meta name="robots" content="noindex" />
+        <!-- Custom HTML head -->
+        <meta content="text/html; charset=utf-8" http-equiv="Content-Type">
+        <meta name="description" content="">
+        <meta name="viewport" content="width=device-width, initial-scale=1">
+        <meta name="theme-color" content="#ffffff" />
+
+        <link rel="icon" href="favicon.svg">
+        <link rel="shortcut icon" href="favicon.png">
+        <link rel="stylesheet" href="css/variables.css">
+        <link rel="stylesheet" href="css/general.css">
+        <link rel="stylesheet" href="css/chrome.css">
+        <link rel="stylesheet" href="css/print.css" media="print">
+        <!-- Fonts -->
+        <link rel="stylesheet" href="FontAwesome/css/font-awesome.css">
+        <link rel="stylesheet" href="fonts/fonts.css">
+        <!-- Highlight.js Stylesheets -->
+        <link rel="stylesheet" href="highlight.css">
+        <link rel="stylesheet" href="tomorrow-night.css">
+        <link rel="stylesheet" href="ayu-highlight.css">
+
+        <!-- Custom theme stylesheets -->
+    </head>
+    <body>
+        <!-- Provide site root to javascript -->
+        <script type="text/javascript">
+            var path_to_root = "";
+            var default_theme = window.matchMedia("(prefers-color-scheme: dark)").matches ? "navy" : "light";
+        </script>
+
+        <!-- Work around some values being stored in localStorage wrapped in quotes -->
+        <script type="text/javascript">
+            try {
+                var theme = localStorage.getItem('mdbook-theme');
+                var sidebar = localStorage.getItem('mdbook-sidebar');
+
+                if (theme.startsWith('"') && theme.endsWith('"')) {
+                    localStorage.setItem('mdbook-theme', theme.slice(1, theme.length - 1));
+                }
+
+                if (sidebar.startsWith('"') && sidebar.endsWith('"')) {
+                    localStorage.setItem('mdbook-sidebar', sidebar.slice(1, sidebar.length - 1));
+                }
+            } catch (e) { }
+        </script>
+
+        <!-- Set the theme before any content is loaded, prevents flash -->
+        <script type="text/javascript">
+            var theme;
+            try { theme = localStorage.getItem('mdbook-theme'); } catch(e) { }
+            if (theme === null || theme === undefined) { theme = default_theme; }
+            var html = document.querySelector('html');
+            html.classList.remove('no-js')
+            html.classList.remove('light')
+            html.classList.add(theme);
+            html.classList.add('js');
+        </script>
+
+        <!-- Hide / unhide sidebar before it is displayed -->
+        <script type="text/javascript">
+            var html = document.querySelector('html');
+            var sidebar = 'hidden';
+            if (document.body.clientWidth >= 1080) {
+                try { sidebar = localStorage.getItem('mdbook-sidebar'); } catch(e) { }
+                sidebar = sidebar || 'visible';
+            }
+            html.classList.remove('sidebar-visible');
+            html.classList.add("sidebar-" + sidebar);
+        </script>
+
+        <nav id="sidebar" class="sidebar" aria-label="Table of contents">
+            <div class="sidebar-scrollbox">
+                <ol class="chapter"><li class="chapter-item expanded "><a href="introduction.html"><strong aria-hidden="true">1.</strong> Introduction</a></li><li class="chapter-item expanded "><a href="rendering.html"><strong aria-hidden="true">2.</strong> Rendering</a></li></ol>
+            </div>
+            <div id="sidebar-resize-handle" class="sidebar-resize-handle"></div>
+        </nav>
+
+        <div id="page-wrapper" class="page-wrapper">
+
+            <div class="page">
+                <div id="menu-bar-hover-placeholder"></div>
+                <div id="menu-bar" class="menu-bar sticky bordered">
+                    <div class="left-buttons">
+                        <button id="sidebar-toggle" class="icon-button" type="button" title="Toggle Table of Contents" aria-label="Toggle Table of Contents" aria-controls="sidebar">
+                            <i class="fa fa-bars"></i>
+                        </button>
+                        <button id="theme-toggle" class="icon-button" type="button" title="Change theme" aria-label="Change theme" aria-haspopup="true" aria-expanded="false" aria-controls="theme-list">
+                            <i class="fa fa-paint-brush"></i>
+                        </button>
+                        <ul id="theme-list" class="theme-popup" aria-label="Themes" role="menu">
+                            <li role="none"><button role="menuitem" class="theme" id="light">Light (default)</button></li>
+                            <li role="none"><button role="menuitem" class="theme" id="rust">Rust</button></li>
+                            <li role="none"><button role="menuitem" class="theme" id="coal">Coal</button></li>
+                            <li role="none"><button role="menuitem" class="theme" id="navy">Navy</button></li>
+                            <li role="none"><button role="menuitem" class="theme" id="ayu">Ayu</button></li>
+                        </ul>
+                        <button id="search-toggle" class="icon-button" type="button" title="Search. (Shortkey: s)" aria-label="Toggle Searchbar" aria-expanded="false" aria-keyshortcuts="S" aria-controls="searchbar">
+                            <i class="fa fa-search"></i>
+                        </button>
+                    </div>
+
+                    <h1 class="menu-title">Birb2D</h1>
+
+                    <div class="right-buttons">
+                        <a href="print.html" title="Print this book" aria-label="Print this book">
+                            <i id="print-button" class="fa fa-print"></i>
+                        </a>
+                    </div>
+                </div>
+
+                <div id="search-wrapper" class="hidden">
+                    <form id="searchbar-outer" class="searchbar-outer">
+                        <input type="search" id="searchbar" name="searchbar" placeholder="Search this book ..." aria-controls="searchresults-outer" aria-describedby="searchresults-header">
+                    </form>
+                    <div id="searchresults-outer" class="searchresults-outer hidden">
+                        <div id="searchresults-header" class="searchresults-header"></div>
+                        <ul id="searchresults">
+                        </ul>
+                    </div>
+                </div>
+                <!-- Apply ARIA attributes after the sidebar and the sidebar toggle button are added to the DOM -->
+                <script type="text/javascript">
+                    document.getElementById('sidebar-toggle').setAttribute('aria-expanded', sidebar === 'visible');
+                    document.getElementById('sidebar').setAttribute('aria-hidden', sidebar !== 'visible');
+                    Array.from(document.querySelectorAll('#sidebar a')).forEach(function(link) {
+                        link.setAttribute('tabIndex', sidebar === 'visible' ? 0 : -1);
+                    });
+                </script>
+
+                <div id="content" class="content">
+                    <main>
+                        <h1 id="introduction"><a class="header" href="#introduction">Introduction</a></h1>
+<div style="break-before: page; page-break-before: always;"></div>
+                    </main>
+
+                    <nav class="nav-wrapper" aria-label="Page navigation">
+                        <!-- Mobile navigation buttons -->
+                        <div style="clear: both"></div>
+                    </nav>
+                </div>
+            </div>
+
+            <nav class="nav-wide-wrapper" aria-label="Page navigation">
+            </nav>
+
+        </div>
+
+        <script type="text/javascript">
+            window.playground_copyable = true;
+        </script>
+        <script src="elasticlunr.min.js" type="text/javascript" charset="utf-8"></script>
+        <script src="mark.min.js" type="text/javascript" charset="utf-8"></script>
+        <script src="searcher.js" type="text/javascript" charset="utf-8"></script>
+        <script src="clipboard.min.js" type="text/javascript" charset="utf-8"></script>
+        <script src="highlight.js" type="text/javascript" charset="utf-8"></script>
+        <script src="book.js" type="text/javascript" charset="utf-8"></script>
+
+        <!-- Custom JS scripts -->
+        <script type="text/javascript">
+        window.addEventListener('load', function() {
+            window.setTimeout(window.print, 100);
+        });
+        </script>
+    </body>
+</html>

docs/rendering.html

@@ -0,0 +1,170 @@
+<!DOCTYPE HTML>
+<html lang="en" class="sidebar-visible no-js light">
+    <head>
+        <!-- Book generated using mdBook -->
+        <meta charset="UTF-8">
+        <title>Rendering - Birb2D</title>
+        <!-- Custom HTML head -->
+        <meta content="text/html; charset=utf-8" http-equiv="Content-Type">
+        <meta name="description" content="">
+        <meta name="viewport" content="width=device-width, initial-scale=1">
+        <meta name="theme-color" content="#ffffff" />
+
+        <link rel="icon" href="favicon.svg">
+        <link rel="shortcut icon" href="favicon.png">
+        <link rel="stylesheet" href="css/variables.css">
+        <link rel="stylesheet" href="css/general.css">
+        <link rel="stylesheet" href="css/chrome.css">
+        <link rel="stylesheet" href="css/print.css" media="print">
+        <!-- Fonts -->
+        <link rel="stylesheet" href="FontAwesome/css/font-awesome.css">
+        <link rel="stylesheet" href="fonts/fonts.css">
+        <!-- Highlight.js Stylesheets -->
+        <link rel="stylesheet" href="highlight.css">
+        <link rel="stylesheet" href="tomorrow-night.css">
+        <link rel="stylesheet" href="ayu-highlight.css">
+
+        <!-- Custom theme stylesheets -->
+    </head>
+    <body>
+        <!-- Provide site root to javascript -->
+        <script type="text/javascript">
+            var path_to_root = "";
+            var default_theme = window.matchMedia("(prefers-color-scheme: dark)").matches ? "navy" : "light";
+        </script>
+
+        <!-- Work around some values being stored in localStorage wrapped in quotes -->
+        <script type="text/javascript">
+            try {
+                var theme = localStorage.getItem('mdbook-theme');
+                var sidebar = localStorage.getItem('mdbook-sidebar');
+
+                if (theme.startsWith('"') && theme.endsWith('"')) {
+                    localStorage.setItem('mdbook-theme', theme.slice(1, theme.length - 1));
+                }
+
+                if (sidebar.startsWith('"') && sidebar.endsWith('"')) {
+                    localStorage.setItem('mdbook-sidebar', sidebar.slice(1, sidebar.length - 1));
+                }
+            } catch (e) { }
+        </script>
+
+        <!-- Set the theme before any content is loaded, prevents flash -->
+        <script type="text/javascript">
+            var theme;
+            try { theme = localStorage.getItem('mdbook-theme'); } catch(e) { }
+            if (theme === null || theme === undefined) { theme = default_theme; }
+            var html = document.querySelector('html');
+            html.classList.remove('no-js')
+            html.classList.remove('light')
+            html.classList.add(theme);
+            html.classList.add('js');
+        </script>
+
+        <!-- Hide / unhide sidebar before it is displayed -->
+        <script type="text/javascript">
+            var html = document.querySelector('html');
+            var sidebar = 'hidden';
+            if (document.body.clientWidth >= 1080) {
+                try { sidebar = localStorage.getItem('mdbook-sidebar'); } catch(e) { }
+                sidebar = sidebar || 'visible';
+            }
+            html.classList.remove('sidebar-visible');
+            html.classList.add("sidebar-" + sidebar);
+        </script>
+
+        <nav id="sidebar" class="sidebar" aria-label="Table of contents">
+            <div class="sidebar-scrollbox">
+                <ol class="chapter"><li class="chapter-item expanded "><a href="introduction.html"><strong aria-hidden="true">1.</strong> Introduction</a></li><li class="chapter-item expanded "><a href="rendering.html" class="active"><strong aria-hidden="true">2.</strong> Rendering</a></li></ol>
+            </div>
+            <div id="sidebar-resize-handle" class="sidebar-resize-handle"></div>
+        </nav>
+
+        <div id="page-wrapper" class="page-wrapper">
+
+            <div class="page">
+                <div id="menu-bar-hover-placeholder"></div>
+                <div id="menu-bar" class="menu-bar sticky bordered">
+                    <div class="left-buttons">
+                        <button id="sidebar-toggle" class="icon-button" type="button" title="Toggle Table of Contents" aria-label="Toggle Table of Contents" aria-controls="sidebar">
+                            <i class="fa fa-bars"></i>
+                        </button>
+                        <button id="theme-toggle" class="icon-button" type="button" title="Change theme" aria-label="Change theme" aria-haspopup="true" aria-expanded="false" aria-controls="theme-list">
+                            <i class="fa fa-paint-brush"></i>
+                        </button>
+                        <ul id="theme-list" class="theme-popup" aria-label="Themes" role="menu">
+                            <li role="none"><button role="menuitem" class="theme" id="light">Light (default)</button></li>
+                            <li role="none"><button role="menuitem" class="theme" id="rust">Rust</button></li>
+                            <li role="none"><button role="menuitem" class="theme" id="coal">Coal</button></li>
+                            <li role="none"><button role="menuitem" class="theme" id="navy">Navy</button></li>
+                            <li role="none"><button role="menuitem" class="theme" id="ayu">Ayu</button></li>
+                        </ul>
+                        <button id="search-toggle" class="icon-button" type="button" title="Search. (Shortkey: s)" aria-label="Toggle Searchbar" aria-expanded="false" aria-keyshortcuts="S" aria-controls="searchbar">
+                            <i class="fa fa-search"></i>
+                        </button>
+                    </div>
+
+                    <h1 class="menu-title">Birb2D</h1>
+
+                    <div class="right-buttons">
+                        <a href="print.html" title="Print this book" aria-label="Print this book">
+                            <i id="print-button" class="fa fa-print"></i>
+                        </a>
+                    </div>
+                </div>
+
+                <div id="search-wrapper" class="hidden">
+                    <form id="searchbar-outer" class="searchbar-outer">
+                        <input type="search" id="searchbar" name="searchbar" placeholder="Search this book ..." aria-controls="searchresults-outer" aria-describedby="searchresults-header">
+                    </form>
+                    <div id="searchresults-outer" class="searchresults-outer hidden">
+                        <div id="searchresults-header" class="searchresults-header"></div>
+                        <ul id="searchresults">
+                        </ul>
+                    </div>
+                </div>
+                <!-- Apply ARIA attributes after the sidebar and the sidebar toggle button are added to the DOM -->
+                <script type="text/javascript">
+                    document.getElementById('sidebar-toggle').setAttribute('aria-expanded', sidebar === 'visible');
+                    document.getElementById('sidebar').setAttribute('aria-hidden', sidebar !== 'visible');
+                    Array.from(document.querySelectorAll('#sidebar a')).forEach(function(link) {
+                        link.setAttribute('tabIndex', sidebar === 'visible' ? 0 : -1);
+                    });
+                </script>
+
+                <div id="content" class="content">
+                    <main>
+                        
+                    </main>
+
+                    <nav class="nav-wrapper" aria-label="Page navigation">
+                        <!-- Mobile navigation buttons -->
+                            <a rel="prev" href="introduction.html" class="mobile-nav-chapters previous" title="Previous chapter" aria-label="Previous chapter" aria-keyshortcuts="Left">
+                                <i class="fa fa-angle-left"></i>
+                            </a>
+                        <div style="clear: both"></div>
+                    </nav>
+                </div>
+            </div>
+
+            <nav class="nav-wide-wrapper" aria-label="Page navigation">
+                    <a rel="prev" href="introduction.html" class="nav-chapters previous" title="Previous chapter" aria-label="Previous chapter" aria-keyshortcuts="Left">
+                        <i class="fa fa-angle-left"></i>
+                    </a>
+            </nav>
+
+        </div>
+
+        <script type="text/javascript">
+            window.playground_copyable = true;
+        </script>
+        <script src="elasticlunr.min.js" type="text/javascript" charset="utf-8"></script>
+        <script src="mark.min.js" type="text/javascript" charset="utf-8"></script>
+        <script src="searcher.js" type="text/javascript" charset="utf-8"></script>
+        <script src="clipboard.min.js" type="text/javascript" charset="utf-8"></script>
+        <script src="highlight.js" type="text/javascript" charset="utf-8"></script>
+        <script src="book.js" type="text/javascript" charset="utf-8"></script>
+
+        <!-- Custom JS scripts -->
+    </body>
+</html>

docs/searcher.js

@@ -0,0 +1,483 @@
+"use strict";
+window.search = window.search || {};
+(function search(search) {
+    // Search functionality
+    //
+    // You can use !hasFocus() to prevent keyhandling in your key
+    // event handlers while the user is typing their search.
+
+    if (!Mark || !elasticlunr) {
+        return;
+    }
+
+    //IE 11 Compatibility from https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/String/startsWith
+    if (!String.prototype.startsWith) {
+        String.prototype.startsWith = function(search, pos) {
+            return this.substr(!pos || pos < 0 ? 0 : +pos, search.length) === search;
+        };
+    }
+
+    var search_wrap = document.getElementById('search-wrapper'),
+        searchbar = document.getElementById('searchbar'),
+        searchbar_outer = document.getElementById('searchbar-outer'),
+        searchresults = document.getElementById('searchresults'),
+        searchresults_outer = document.getElementById('searchresults-outer'),
+        searchresults_header = document.getElementById('searchresults-header'),
+        searchicon = document.getElementById('search-toggle'),
+        content = document.getElementById('content'),
+
+        searchindex = null,
+        doc_urls = [],
+        results_options = {
+            teaser_word_count: 30,
+            limit_results: 30,
+        },
+        search_options = {
+            bool: "AND",
+            expand: true,
+            fields: {
+                title: {boost: 1},
+                body: {boost: 1},
+                breadcrumbs: {boost: 0}
+            }
+        },
+        mark_exclude = [],
+        marker = new Mark(content),
+        current_searchterm = "",
+        URL_SEARCH_PARAM = 'search',
+        URL_MARK_PARAM = 'highlight',
+        teaser_count = 0,
+
+        SEARCH_HOTKEY_KEYCODE = 83,
+        ESCAPE_KEYCODE = 27,
+        DOWN_KEYCODE = 40,
+        UP_KEYCODE = 38,
+        SELECT_KEYCODE = 13;
+
+    function hasFocus() {
+        return searchbar === document.activeElement;
+    }
+
+    function removeChildren(elem) {
+        while (elem.firstChild) {
+            elem.removeChild(elem.firstChild);
+        }
+    }
+
+    // Helper to parse a url into its building blocks.
+    function parseURL(url) {
+        var a =  document.createElement('a');
+        a.href = url;
+        return {
+            source: url,
+            protocol: a.protocol.replace(':',''),
+            host: a.hostname,
+            port: a.port,
+            params: (function(){
+                var ret = {};
+                var seg = a.search.replace(/^\?/,'').split('&');
+                var len = seg.length, i = 0, s;
+                for (;i<len;i++) {
+                    if (!seg[i]) { continue; }
+                    s = seg[i].split('=');
+                    ret[s[0]] = s[1];
+                }
+                return ret;
+            })(),
+            file: (a.pathname.match(/\/([^/?#]+)$/i) || [,''])[1],
+            hash: a.hash.replace('#',''),
+            path: a.pathname.replace(/^([^/])/,'/$1')
+        };
+    }
+    
+    // Helper to recreate a url string from its building blocks.
+    function renderURL(urlobject) {
+        var url = urlobject.protocol + "://" + urlobject.host;
+        if (urlobject.port != "") {
+            url += ":" + urlobject.port;
+        }
+        url += urlobject.path;
+        var joiner = "?";
+        for(var prop in urlobject.params) {
+            if(urlobject.params.hasOwnProperty(prop)) {
+                url += joiner + prop + "=" + urlobject.params[prop];
+                joiner = "&";
+            }
+        }
+        if (urlobject.hash != "") {
+            url += "#" + urlobject.hash;
+        }
+        return url;
+    }
+    
+    // Helper to escape html special chars for displaying the teasers
+    var escapeHTML = (function() {
+        var MAP = {
+            '&': '&amp;',
+            '<': '&lt;',
+            '>': '&gt;',
+            '"': '&#34;',
+            "'": '&#39;'
+        };
+        var repl = function(c) { return MAP[c]; };
+        return function(s) {
+            return s.replace(/[&<>'"]/g, repl);
+        };
+    })();
+    
+    function formatSearchMetric(count, searchterm) {
+        if (count == 1) {
+            return count + " search result for '" + searchterm + "':";
+        } else if (count == 0) {
+            return "No search results for '" + searchterm + "'.";
+        } else {
+            return count + " search results for '" + searchterm + "':";
+        }
+    }
+    
+    function formatSearchResult(result, searchterms) {
+        var teaser = makeTeaser(escapeHTML(result.doc.body), searchterms);
+        teaser_count++;
+
+        // The ?URL_MARK_PARAM= parameter belongs inbetween the page and the #heading-anchor
+        var url = doc_urls[result.ref].split("#");
+        if (url.length == 1) { // no anchor found
+            url.push("");
+        }
+
+        // encodeURIComponent escapes all chars that could allow an XSS except
+        // for '. Due to that we also manually replace ' with its url-encoded
+        // representation (%27).
+        var searchterms = encodeURIComponent(searchterms.join(" ")).replace(/\'/g, "%27");
+
+        return '<a href="' + path_to_root + url[0] + '?' + URL_MARK_PARAM + '=' + searchterms + '#' + url[1]
+            + '" aria-details="teaser_' + teaser_count + '">' + result.doc.breadcrumbs + '</a>'
+            + '<span class="teaser" id="teaser_' + teaser_count + '" aria-label="Search Result Teaser">' 
+            + teaser + '</span>';
+    }
+    
+    function makeTeaser(body, searchterms) {
+        // The strategy is as follows:
+        // First, assign a value to each word in the document:
+        //  Words that correspond to search terms (stemmer aware): 40
+        //  Normal words: 2
+        //  First word in a sentence: 8
+        // Then use a sliding window with a constant number of words and count the
+        // sum of the values of the words within the window. Then use the window that got the
+        // maximum sum. If there are multiple maximas, then get the last one.
+        // Enclose the terms in <em>.
+        var stemmed_searchterms = searchterms.map(function(w) {
+            return elasticlunr.stemmer(w.toLowerCase());
+        });
+        var searchterm_weight = 40;
+        var weighted = []; // contains elements of ["word", weight, index_in_document]
+        // split in sentences, then words
+        var sentences = body.toLowerCase().split('. ');
+        var index = 0;
+        var value = 0;
+        var searchterm_found = false;
+        for (var sentenceindex in sentences) {
+            var words = sentences[sentenceindex].split(' ');
+            value = 8;
+            for (var wordindex in words) {
+                var word = words[wordindex];
+                if (word.length > 0) {
+                    for (var searchtermindex in stemmed_searchterms) {
+                        if (elasticlunr.stemmer(word).startsWith(stemmed_searchterms[searchtermindex])) {
+                            value = searchterm_weight;
+                            searchterm_found = true;
+                        }
+                    };
+                    weighted.push([word, value, index]);
+                    value = 2;
+                }
+                index += word.length;
+                index += 1; // ' ' or '.' if last word in sentence
+            };
+            index += 1; // because we split at a two-char boundary '. '
+        };
+
+        if (weighted.length == 0) {
+            return body;
+        }
+
+        var window_weight = [];
+        var window_size = Math.min(weighted.length, results_options.teaser_word_count);
+
+        var cur_sum = 0;
+        for (var wordindex = 0; wordindex < window_size; wordindex++) {
+            cur_sum += weighted[wordindex][1];
+        };
+        window_weight.push(cur_sum);
+        for (var wordindex = 0; wordindex < weighted.length - window_size; wordindex++) {
+            cur_sum -= weighted[wordindex][1];
+            cur_sum += weighted[wordindex + window_size][1];
+            window_weight.push(cur_sum);
+        };
+
+        if (searchterm_found) {
+            var max_sum = 0;
+            var max_sum_window_index = 0;
+            // backwards
+            for (var i = window_weight.length - 1; i >= 0; i--) {
+                if (window_weight[i] > max_sum) {
+                    max_sum = window_weight[i];
+                    max_sum_window_index = i;
+                }
+            };
+        } else {
+            max_sum_window_index = 0;
+        }
+
+        // add <em/> around searchterms
+        var teaser_split = [];
+        var index = weighted[max_sum_window_index][2];
+        for (var i = max_sum_window_index; i < max_sum_window_index+window_size; i++) {
+            var word = weighted[i];
+            if (index < word[2]) {
+                // missing text from index to start of `word`
+                teaser_split.push(body.substring(index, word[2]));
+                index = word[2];
+            }
+            if (word[1] == searchterm_weight) {
+                teaser_split.push("<em>")
+            }
+            index = word[2] + word[0].length;
+            teaser_split.push(body.substring(word[2], index));
+            if (word[1] == searchterm_weight) {
+                teaser_split.push("</em>")
+            }
+        };
+
+        return teaser_split.join('');
+    }
+
+    function init(config) {
+        results_options = config.results_options;
+        search_options = config.search_options;
+        searchbar_outer = config.searchbar_outer;
+        doc_urls = config.doc_urls;
+        searchindex = elasticlunr.Index.load(config.index);
+
+        // Set up events
+        searchicon.addEventListener('click', function(e) { searchIconClickHandler(); }, false);
+        searchbar.addEventListener('keyup', function(e) { searchbarKeyUpHandler(); }, false);
+        document.addEventListener('keydown', function(e) { globalKeyHandler(e); }, false);
+        // If the user uses the browser buttons, do the same as if a reload happened
+        window.onpopstate = function(e) { doSearchOrMarkFromUrl(); };
+        // Suppress "submit" events so the page doesn't reload when the user presses Enter
+        document.addEventListener('submit', function(e) { e.preventDefault(); }, false);
+
+        // If reloaded, do the search or mark again, depending on the current url parameters
+        doSearchOrMarkFromUrl();
+    }
+    
+    function unfocusSearchbar() {
+        // hacky, but just focusing a div only works once
+        var tmp = document.createElement('input');
+        tmp.setAttribute('style', 'position: absolute; opacity: 0;');
+        searchicon.appendChild(tmp);
+        tmp.focus();
+        tmp.remove();
+    }
+    
+    // On reload or browser history backwards/forwards events, parse the url and do search or mark
+    function doSearchOrMarkFromUrl() {
+        // Check current URL for search request
+        var url = parseURL(window.location.href);
+        if (url.params.hasOwnProperty(URL_SEARCH_PARAM)
+            && url.params[URL_SEARCH_PARAM] != "") {
+            showSearch(true);
+            searchbar.value = decodeURIComponent(
+                (url.params[URL_SEARCH_PARAM]+'').replace(/\+/g, '%20'));
+            searchbarKeyUpHandler(); // -> doSearch()
+        } else {
+            showSearch(false);
+        }
+
+        if (url.params.hasOwnProperty(URL_MARK_PARAM)) {
+            var words = decodeURIComponent(url.params[URL_MARK_PARAM]).split(' ');
+            marker.mark(words, {
+                exclude: mark_exclude
+            });
+
+            var markers = document.querySelectorAll("mark");
+            function hide() {
+                for (var i = 0; i < markers.length; i++) {
+                    markers[i].classList.add("fade-out");
+                    window.setTimeout(function(e) { marker.unmark(); }, 300);
+                }
+            }
+            for (var i = 0; i < markers.length; i++) {
+                markers[i].addEventListener('click', hide);
+            }
+        }
+    }
+    
+    // Eventhandler for keyevents on `document`
+    function globalKeyHandler(e) {
+        if (e.altKey || e.ctrlKey || e.metaKey || e.shiftKey || e.target.type === 'textarea' || e.target.type === 'text') { return; }
+
+        if (e.keyCode === ESCAPE_KEYCODE) {
+            e.preventDefault();
+            searchbar.classList.remove("active");
+            setSearchUrlParameters("",
+                (searchbar.value.trim() !== "") ? "push" : "replace");
+            if (hasFocus()) {
+                unfocusSearchbar();
+            }
+            showSearch(false);
+            marker.unmark();
+        } else if (!hasFocus() && e.keyCode === SEARCH_HOTKEY_KEYCODE) {
+            e.preventDefault();
+            showSearch(true);
+            window.scrollTo(0, 0);
+            searchbar.select();
+        } else if (hasFocus() && e.keyCode === DOWN_KEYCODE) {
+            e.preventDefault();
+            unfocusSearchbar();
+            searchresults.firstElementChild.classList.add("focus");
+        } else if (!hasFocus() && (e.keyCode === DOWN_KEYCODE
+                                || e.keyCode === UP_KEYCODE
+                                || e.keyCode === SELECT_KEYCODE)) {
+            // not `:focus` because browser does annoying scrolling
+            var focused = searchresults.querySelector("li.focus");
+            if (!focused) return;
+            e.preventDefault();
+            if (e.keyCode === DOWN_KEYCODE) {
+                var next = focused.nextElementSibling;
+                if (next) {
+                    focused.classList.remove("focus");
+                    next.classList.add("focus");
+                }
+            } else if (e.keyCode === UP_KEYCODE) {
+                focused.classList.remove("focus");
+                var prev = focused.previousElementSibling;
+                if (prev) {
+                    prev.classList.add("focus");
+                } else {
+                    searchbar.select();
+                }
+            } else { // SELECT_KEYCODE
+                window.location.assign(focused.querySelector('a'));
+            }
+        }
+    }
+    
+    function showSearch(yes) {
+        if (yes) {
+            search_wrap.classList.remove('hidden');
+            searchicon.setAttribute('aria-expanded', 'true');
+        } else {
+            search_wrap.classList.add('hidden');
+            searchicon.setAttribute('aria-expanded', 'false');
+            var results = searchresults.children;
+            for (var i = 0; i < results.length; i++) {
+                results[i].classList.remove("focus");
+            }
+        }
+    }
+
+    function showResults(yes) {
+        if (yes) {
+            searchresults_outer.classList.remove('hidden');
+        } else {
+            searchresults_outer.classList.add('hidden');
+        }
+    }
+
+    // Eventhandler for search icon
+    function searchIconClickHandler() {
+        if (search_wrap.classList.contains('hidden')) {
+            showSearch(true);
+            window.scrollTo(0, 0);
+            searchbar.select();
+        } else {
+            showSearch(false);
+        }
+    }
+    
+    // Eventhandler for keyevents while the searchbar is focused
+    function searchbarKeyUpHandler() {
+        var searchterm = searchbar.value.trim();
+        if (searchterm != "") {
+            searchbar.classList.add("active");
+            doSearch(searchterm);
+        } else {
+            searchbar.classList.remove("active");
+            showResults(false);
+            removeChildren(searchresults);
+        }
+
+        setSearchUrlParameters(searchterm, "push_if_new_search_else_replace");
+
+        // Remove marks
+        marker.unmark();
+    }
+    
+    // Update current url with ?URL_SEARCH_PARAM= parameter, remove ?URL_MARK_PARAM and #heading-anchor .
+    // `action` can be one of "push", "replace", "push_if_new_search_else_replace"
+    // and replaces or pushes a new browser history item.
+    // "push_if_new_search_else_replace" pushes if there is no `?URL_SEARCH_PARAM=abc` yet.
+    function setSearchUrlParameters(searchterm, action) {
+        var url = parseURL(window.location.href);
+        var first_search = ! url.params.hasOwnProperty(URL_SEARCH_PARAM);
+        if (searchterm != "" || action == "push_if_new_search_else_replace") {
+            url.params[URL_SEARCH_PARAM] = searchterm;
+            delete url.params[URL_MARK_PARAM];
+            url.hash = "";
+        } else {
+            delete url.params[URL_MARK_PARAM];
+            delete url.params[URL_SEARCH_PARAM];
+        }
+        // A new search will also add a new history item, so the user can go back
+        // to the page prior to searching. A updated search term will only replace
+        // the url.
+        if (action == "push" || (action == "push_if_new_search_else_replace" && first_search) ) {
+            history.pushState({}, document.title, renderURL(url));
+        } else if (action == "replace" || (action == "push_if_new_search_else_replace" && !first_search) ) {
+            history.replaceState({}, document.title, renderURL(url));
+        }
+    }
+    
+    function doSearch(searchterm) {
+
+        // Don't search the same twice
+        if (current_searchterm == searchterm) { return; }
+        else { current_searchterm = searchterm; }
+
+        if (searchindex == null) { return; }
+
+        // Do the actual search
+        var results = searchindex.search(searchterm, search_options);
+        var resultcount = Math.min(results.length, results_options.limit_results);
+
+        // Display search metrics
+        searchresults_header.innerText = formatSearchMetric(resultcount, searchterm);
+
+        // Clear and insert results
+        var searchterms  = searchterm.split(' ');
+        removeChildren(searchresults);
+        for(var i = 0; i < resultcount ; i++){
+            var resultElem = document.createElement('li');
+            resultElem.innerHTML = formatSearchResult(results[i], searchterms);
+            searchresults.appendChild(resultElem);
+        }
+
+        // Display results
+        showResults(true);
+    }
+
+    fetch(path_to_root + 'searchindex.json')
+        .then(response => response.json())
+        .then(json => init(json))        
+        .catch(error => { // Try to load searchindex.js if fetch failed
+            var script = document.createElement('script');
+            script.src = path_to_root + 'searchindex.js';
+            script.onload = () => init(window.search);
+            document.head.appendChild(script);
+        });
+
+    // Exported functions
+    search.hasFocus = hasFocus;
+})(window.search);

docs/searchindex.js

@@ -0,0 +1 @@
+Object.assign(window.search, {"doc_urls":["introduction.html#introduction"],"index":{"documentStore":{"docInfo":{"0":{"body":0,"breadcrumbs":2,"title":1}},"docs":{"0":{"body":"","breadcrumbs":"Introduction » Introduction","id":"0","title":"Introduction"}},"length":1,"save":true},"fields":["title","body","breadcrumbs"],"index":{"body":{"root":{"df":0,"docs":{},"i":{"df":0,"docs":{},"n":{"df":0,"docs":{},"t":{"df":0,"docs":{},"r":{"df":0,"docs":{},"o":{"d":{"df":0,"docs":{},"u":{"c":{"df":0,"docs":{},"t":{"df":1,"docs":{"0":{"tf":1.0}}}},"df":0,"docs":{}}},"df":0,"docs":{}}}}}}}},"breadcrumbs":{"root":{"df":0,"docs":{},"i":{"df":0,"docs":{},"n":{"df":0,"docs":{},"t":{"df":0,"docs":{},"r":{"df":0,"docs":{},"o":{"d":{"df":0,"docs":{},"u":{"c":{"df":0,"docs":{},"t":{"df":1,"docs":{"0":{"tf":1.7320508075688772}}}},"df":0,"docs":{}}},"df":0,"docs":{}}}}}}}},"title":{"root":{"df":0,"docs":{},"i":{"df":0,"docs":{},"n":{"df":0,"docs":{},"t":{"df":0,"docs":{},"r":{"df":0,"docs":{},"o":{"d":{"df":0,"docs":{},"u":{"c":{"df":0,"docs":{},"t":{"df":1,"docs":{"0":{"tf":1.0}}}},"df":0,"docs":{}}},"df":0,"docs":{}}}}}}}}},"lang":"English","pipeline":["trimmer","stopWordFilter","stemmer"],"ref":"id","version":"0.9.5"},"results_options":{"limit_results":30,"teaser_word_count":30},"search_options":{"bool":"OR","expand":true,"fields":{"body":{"boost":1},"breadcrumbs":{"boost":1},"title":{"boost":2}}}});

docs/searchindex.json

@@ -0,0 +1 @@
+{"doc_urls":["introduction.html#introduction"],"index":{"documentStore":{"docInfo":{"0":{"body":0,"breadcrumbs":2,"title":1}},"docs":{"0":{"body":"","breadcrumbs":"Introduction » Introduction","id":"0","title":"Introduction"}},"length":1,"save":true},"fields":["title","body","breadcrumbs"],"index":{"body":{"root":{"df":0,"docs":{},"i":{"df":0,"docs":{},"n":{"df":0,"docs":{},"t":{"df":0,"docs":{},"r":{"df":0,"docs":{},"o":{"d":{"df":0,"docs":{},"u":{"c":{"df":0,"docs":{},"t":{"df":1,"docs":{"0":{"tf":1.0}}}},"df":0,"docs":{}}},"df":0,"docs":{}}}}}}}},"breadcrumbs":{"root":{"df":0,"docs":{},"i":{"df":0,"docs":{},"n":{"df":0,"docs":{},"t":{"df":0,"docs":{},"r":{"df":0,"docs":{},"o":{"d":{"df":0,"docs":{},"u":{"c":{"df":0,"docs":{},"t":{"df":1,"docs":{"0":{"tf":1.7320508075688772}}}},"df":0,"docs":{}}},"df":0,"docs":{}}}}}}}},"title":{"root":{"df":0,"docs":{},"i":{"df":0,"docs":{},"n":{"df":0,"docs":{},"t":{"df":0,"docs":{},"r":{"df":0,"docs":{},"o":{"d":{"df":0,"docs":{},"u":{"c":{"df":0,"docs":{},"t":{"df":1,"docs":{"0":{"tf":1.0}}}},"df":0,"docs":{}}},"df":0,"docs":{}}}}}}}}},"lang":"English","pipeline":["trimmer","stopWordFilter","stemmer"],"ref":"id","version":"0.9.5"},"results_options":{"limit_results":30,"teaser_word_count":30},"search_options":{"bool":"OR","expand":true,"fields":{"body":{"boost":1},"breadcrumbs":{"boost":1},"title":{"boost":2}}}}

docs/tomorrow-night.css

@@ -0,0 +1,104 @@
+/* Tomorrow Night Theme */
+/* http://jmblog.github.com/color-themes-for-google-code-highlightjs */
+/* Original theme - https://github.com/chriskempson/tomorrow-theme */
+/* http://jmblog.github.com/color-themes-for-google-code-highlightjs */
+
+/* Tomorrow Comment */
+.hljs-comment {
+  color: #969896;
+}
+
+/* Tomorrow Red */
+.hljs-variable,
+.hljs-attribute,
+.hljs-tag,
+.hljs-regexp,
+.ruby .hljs-constant,
+.xml .hljs-tag .hljs-title,
+.xml .hljs-pi,
+.xml .hljs-doctype,
+.html .hljs-doctype,
+.css .hljs-id,
+.css .hljs-class,
+.css .hljs-pseudo {
+  color: #cc6666;
+}
+
+/* Tomorrow Orange */
+.hljs-number,
+.hljs-preprocessor,
+.hljs-pragma,
+.hljs-built_in,
+.hljs-literal,
+.hljs-params,
+.hljs-constant {
+  color: #de935f;
+}
+
+/* Tomorrow Yellow */
+.ruby .hljs-class .hljs-title,
+.css .hljs-rule .hljs-attribute {
+  color: #f0c674;
+}
+
+/* Tomorrow Green */
+.hljs-string,
+.hljs-value,
+.hljs-inheritance,
+.hljs-header,
+.hljs-name,
+.ruby .hljs-symbol,
+.xml .hljs-cdata {
+  color: #b5bd68;
+}
+
+/* Tomorrow Aqua */
+.hljs-title,
+.css .hljs-hexcolor {
+  color: #8abeb7;
+}
+
+/* Tomorrow Blue */
+.hljs-function,
+.python .hljs-decorator,
+.python .hljs-title,
+.ruby .hljs-function .hljs-title,
+.ruby .hljs-title .hljs-keyword,
+.perl .hljs-sub,
+.javascript .hljs-title,
+.coffeescript .hljs-title {
+  color: #81a2be;
+}
+
+/* Tomorrow Purple */
+.hljs-keyword,
+.javascript .hljs-function {
+  color: #b294bb;
+}
+
+.hljs {
+  display: block;
+  overflow-x: auto;
+  background: #1d1f21;
+  color: #c5c8c6;
+  padding: 0.5em;
+  -webkit-text-size-adjust: none;
+}
+
+.coffeescript .javascript,
+.javascript .xml,
+.tex .hljs-formula,
+.xml .javascript,
+.xml .vbscript,
+.xml .css,
+.xml .hljs-cdata {
+  opacity: 0.5;
+}
+
+.hljs-addition {
+  color: #718c00;
+}
+
+.hljs-deletion {
+  color: #c82829;
+}

editor/src/editor.cpp

@@ -0,0 +1,112 @@
+#include "../../include/Audio.hpp"
+#include "../../include/Editor.hpp"
+#include "../../include/RenderWindow.hpp"
+#include "../../include/Widgets.hpp"
+#include "../../include/Entity.hpp"
+#include "../../include/Values.hpp"
+#include "../../include/Logger.hpp"
+
+#include <iostream>
+#include <vector>
+
+void Entry();
+
+#ifndef PLATFORM_WIN
+int main(int argc, char* argv[])
+{
+	Entry();
+	return 0;
+}
+#else
+int WinMain(int argc, char* argv[])
+{
+	Entry();
+	return 0;
+}
+#endif
+
+void printHello()
+{
+	Debug::Log("Button click working");
+}
+
+void Entry()
+{
+	Debug::Log("Engine startpoint");
+	int refreshRate = 240;
+	Birb2D::RenderWindow window("Birb2D Editor", 1280, 720, refreshRate);
+
+	// ### Editor loop ###
+	std::vector<Birb2D::Entity> entities = {};
+
+	// Widgets
+	Birb2D::Font baseFont("../res/fonts/manaspace/manaspc.ttf", Colors::Black, 16);
+	Birb2D::Font buttonFont("../res/fonts/freefont/FreeMono.ttf", Colors::White, 12);
+	Birb2D::Widgets::TopBar topbar(window, 32, Colors::Black, baseFont);
+
+	std::vector<Birb2D::Widgets::Button> buttons;
+	Birb2D::Widgets::Button testButton(window, Rect(50, 50, 120, 30), Colors::LightGray, "A button", buttonFont, printHello);
+
+	buttons.push_back(testButton);
+
+	Birb2D::Texture texture;
+	texture.sdlTexture = window.loadTexture("../res/textures/giga_stretch.png");
+	Birb2D::Entity testPicture("Test texture", Vector2f(0, 32), 0.4, Vector2f(1280, 720), texture);
+
+	SDL_Event event;
+	bool editorRunning = true;
+	while (editorRunning)
+	{
+		window.timestepStart();
+		while (window.timestepRunning())
+		{
+			while (SDL_PollEvent(&event) != 0)
+			{
+				window.handleBasicWindowEvents(event, &editorRunning);
+
+				switch (event.type)
+				{
+					case (SDL_WINDOWEVENT):
+						if (event.window.event == SDL_WINDOWEVENT_RESIZED)
+						{
+							window.SetWindowSize(event.window.data1, event.window.data2);
+						}
+						break;
+
+					case (SDL_MOUSEBUTTONDOWN):
+						for (int i = 0; i < (int)buttons.size(); i++)
+						{
+							buttons[i].refresh(Birb2D::Widgets::RefreshAction::Click);
+						}
+						break;
+
+					default:
+						break;
+				}
+
+			}
+
+			window.timestepStep();
+		}
+		window.timestepEnd();
+
+		// ###### Render stuff ######
+		window.clear();
+		topbar.refresh(window.getDimensions());
+		window.render(testPicture);
+		testButton.refresh(Birb2D::Widgets::RefreshAction::Render);
+
+		window.display();
+		// ##########################
+	}
+
+	// ### End of editor loop ###
+	Debug::Log("Closing the editor");
+
+	// Stop audio
+	Mix_CloseAudio();
+	Mix_Quit();
+
+	TTF_Quit();
+	SDL_Quit();
+}

games/Ping-Pong/res/fonts/freefont/AUTHORS

@@ -0,0 +1,242 @@
+-*- mode:text; coding:utf-8; -*-
+                        GNU FreeFont Authors
+                        ====================
+
+The FreeFont collection is being maintained by
+	Steve White <stevan.white AT googlemail.com>
+The folowing list cites the other contributors that contributed to
+particular ISO 10646 blocks.
+
+* URW++ Design & Development GmbH <http://www.urwpp.de/>
+
+	Basic Latin				(U+0041-U+007A)
+	Latin-1 Supplement                      (U+00C0-U+00FF) (most)
+	Latin Extended-A                        (U+0100-U+017F)
+	Spacing Modifier Letters		(U+02B0-U+02FF)
+	Mathematical Operators			(U+2200-U+22FF) (parts)
+	Block Elements				(U+2580-U+259F)
+	Dingbats				(U+2700-U+27BF)
+
+* Yannis Haralambous <yannis.haralambous AT enst-bretagne.fr> and John
+  Plaice <plaice AT omega.cse.unsw.edu.au>
+
+	Latin Extended-B                        (U+0180-U+024F)
+	IPA Extensions				(U+0250-U+02AF)
+	Greek					(U+0370-U+03FF)
+	Armenian				(U+0530-U+058F)
+	Hebrew					(U+0590-U+05FF)
+	Arabic					(U+0600-U+06FF)
+	Currency Symbols			(U+20A0-U+20CF)
+	Arabic Presentation Forms-A		(U+FB50-U+FDFF)
+	Arabic Presentation Forms-B		(U+FE70-U+FEFF)
+
+* Yannis Haralambous and Wellcome Institute
+
+	Sinhala					(U+0D80-U+0DFF)
+
+* Young U. Ryu <ryoung AT utdallas.edu>
+
+	Arrows					(U+2190-U+21FF)
+	Mathematical Symbols			(U+2200-U+22FF)
+	Mathematical Alphanumeric Symbols       (U+1D400-U+1D7FF)
+
+* Valek Filippov <frob AT df.ru>
+
+	Cyrillic				(U+0400-U+04FF)
+
+* Wadalab Kanji Comittee
+
+	Hiragana				(U+3040-U+309F)
+	Katakana				(U+30A0-U+30FF)
+
+* Angelo Haritsis <ah AT computer.org>
+
+	Greek					(U+0370-U+03FF)
+
+* Yannis Haralambous and Virach Sornlertlamvanich
+
+	Thai					(U+0E00-U+0E7F)
+
+* Shaheed R. Haque <srhaque AT iee.org>
+
+	Bengali					(U+0980-U+09FF)
+
+* Sam Stepanyan <sam AT arminco.com>
+
+	Armenian				(U+0530-U+058F)
+
+* Mohamed Ishan <ishan AT mitf.f2s.com>
+
+	Thaana					(U+0780-U+07BF)
+
+* Sushant Kumar Dash <sushant AT writeme.com>
+
+	Oriya					(U+0B00-U+0B7F)
+
+* Harsh Kumar <harshkumar AT vsnl.com>
+
+	Devanagari				(U+0900-U+097F)
+	Bengali					(U+0980-U+09FF)
+	Gurmukhi				(U+0A00-U+0A7F)
+	Gujarati				(U+0A80-U+0AFF)
+
+* Prasad A. Chodavarapu <chprasad AT hotmail.com>
+
+	Telugu					(U+0C00-U+0C7F)
+
+* Frans Velthuis <velthuis AT rc.rug.nl> and Anshuman Pandey
+  <apandey AT u.washington.edu> 
+
+	Devanagari				(U+0900-U+097F)
+
+* Hardip Singh Pannu <HSPannu AT aol.com>
+
+	Gurmukhi				(U+0A00-U+0A7F)
+
+* Jeroen Hellingman <jehe AT kabelfoon.nl>
+
+	Oriya					(U+0B00-U+0B7F)
+	Malayalam				(U+0D00-U+0D7F)
+
+* Thomas Ridgeway <email needed>
+
+	Tamil					(U+0B80-U+0BFF)
+
+* Berhanu Beyene <1beyene AT informatik.uni-hamburg.de>,
+  Prof. Dr. Manfred Kudlek <kudlek AT informatik.uni-hamburg.de>, Olaf
+  Kummer <kummer AT informatik.uni-hamburg.de>, and Jochen Metzinger <?>
+
+	Ethiopic				(U+1200-U+137F)
+
+* Maxim Iorsh <iorsh AT users.sourceforge.net>
+
+	Hebrew					(U+0590-U+05FF)
+
+* Vyacheslav Dikonov <sdiconov AT mail.ru>
+
+	Syriac					(U+0700-U+074A)
+	Braille					(U+2800-U+28FF)
+
+* Panayotis Katsaloulis <panayotis AT panayotis.com>
+
+	Greek Extended				(U+1F00-U+1FFF)
+
+* M.S. Sridhar <mssridhar AT vsnl.com>
+
+	Devanagari				(U+0900-U+097F)
+	Bengali					(U+0980-U+09FF)
+	Gurmukhi				(U+0A00-U+0A7F)
+	Gujarati				(U+0A80-U+0AFF)
+	Oriya					(U+0B00-U+0B7F)
+	Tamil					(U+0B80-U+0BFF)
+	Telugu					(U+0C00-U+0C7F)
+	Kannada					(U+0C80-U+0CFF)	
+	Malayalam				(U+0D00-U+0D7F)
+
+* DMS Electronics, The Sri Lanka Tipitaka Project, and Noah Levitt
+  <nlevitt AT columbia.edu>
+
+	Sinhala					(U+0D80-U+0DFF)
+        
+* Dan Shurovich Chirkov <dansh AT chirkov.com>
+
+	Cyrillic				(U+0400-U+04FF)
+
+* Abbas Izad <abbasizad AT hotmail.com>
+
+	Arabic					(U+0600-U+06FF)
+	Arabic Presentation Forms-A		(U+FB50-U+FDFF)
+	Arabic Presentation Forms-B		(U+FE70-U+FEFF)
+
+* Denis Jacquerye <moyogo AT gmail.com>
+
+	Latin Extended-B                        (U+0180-U+024F)
+	IPA Extensions				(U+0250-U+02AF)
+
+* K.H. Hussain <hussain AT kfri.org> and R. Chitrajan
+
+	Malayalam				(U+0D00-U+0D7F)
+
+* Solaiman Karim <solaiman AT ekushey.org> and Omi Azad <omi AT ekushey.org>
+
+	Bengali					(U+0980-U+09FF)
+
+* Sonali Sonania <sonalisonania AT gmail.com> and Monika Shah
+  <monikapatira AT gmail.com>
+
+	Devanagari				(U+0900-U+097F)
+	Gujarati				(U+0A80-U+0AFF)
+
+* Pravin Satpute <pravin.d.s AT gmail.com>, Bageshri Salvi
+  <sbagrshri AT yahoo.co.in>, Rahul Bhalerao <b.rahul.pm AT gmail.com> and
+  Sandeep Shedmake <sandeep.shedmake AT gmail.com>
+
+	Devanagari				(U+0900-U+097F)
+	Gujarati				(U+0A80-U+0AFF)
+	Oriya					(U+0B00-U+0B7F)
+	Malayalam				(U+0D00-U+0D7F)
+	Tamil					(U+0B80-U+0BFF)
+
+* Kulbir Singh Thind
+
+	Gurmukhi				(U+0A00-U+0A7F)
+
+* Gia Shervashidze <giasher AT telenet.ge>
+
+        Georgian				(U+10A0-U+10FF)
+
+* Daniel Johnson
+
+	Armenian (serif)                        (U+0530-U+058F)
+	Cherokee                                (U+13A0-U+13FF)
+	Unified Canadian Aboriginal Syllabics   (U+1400-U+167F)
+	UCAS Extended                           (U+18B0-U+18F5)
+	Tifinagh                                (U+2D30-U+2D7F)
+	Vai                                     (U+A500-U+A62B)
+	Latin Extended-D (Mayanist letters)     (U+A720-U+A7FF)
+	Kayah Li                                (U+A900-U+A92F)
+	Osmanya                                 (U+10480-U+104a7)
+
+* George Douros
+
+	Gothic                                  (U+10330-U+1034F)
+	Phoenecian                              (U+10900-U+1091F)
+	Byzantine Musical Symbols               (U+1D000-U+1D0FF)
+	Western Musical Symbols                 (U+1D100-U+1D1DF)
+	Mathematical Alphanumeric Symbols       (U+1D400-U+1D7FF)
+	Mah Jong Tiles                          (U+1F000-U+1F02B)
+	Dominoes                                (U+1F030-U+1F093)
+
+* Steve White <stevan_white AT gmail.com>
+	Glagolitic                              (U+2C00-U+2C5F)
+	Coptic                                  (U+2C80-U+2CFF)
+	Arabic					(U+0600-U+06FF) (Mono)
+	Old Italic                              (U+10300-U+1032F)
+
+* Pavel Skrylev is responsible for
+	Cyrillic Extended-A                     (U+2DEO-U+2DFF)
+  as well as many of the additions to
+	Cyrillic Extended-B                     (U+A640-U+A65F)
+
+* Mark Williamson
+  Made the MPH 2 Damase font, from which 
+	Hanunóo                                 (U+1720-U+173F)
+	Buginese                                (U+1A00-U+1A1F)
+	Tai Le                                  (U+1950-U+197F)
+	Ugaritic                                (U+10380-U+1039F)
+	Old Persian                             (U+103A0-U+103DF)
+
+* Masoud Pourmoosa
+	Arabic					(U+0600-U+06FF)
+
+* Emmanuel Vallois
+	Python scripts, support
+
+* Primož Peterlin <primoz.peterlin AT biofiz.mf.uni-lj.si>
+  maintained FreeFont for several years, and is thanked for all his work.
+
+Please see the CREDITS file for details on who contributed particular
+subsets of the glyphs in font files.
+
+--------------------------------------------------------------------------
+$Id: AUTHORS,v 1.23 2010-09-11 13:24:11 Stevan_White Exp $

games/Ping-Pong/res/fonts/freefont/COPYING

@@ -0,0 +1,674 @@
+                    GNU GENERAL PUBLIC LICENSE
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+
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+
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+
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+
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+
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+<http://www.gnu.org/licenses/>.
+
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+the library.  If this is what you want to do, use the GNU Lesser General
+Public License instead of this License.  But first, please read
+<http://www.gnu.org/philosophy/why-not-lgpl.html>.

games/Ping-Pong/res/fonts/freefont/CREDITS

@@ -0,0 +1,597 @@
+-*- mode:text; coding:utf-8; -*-
+                         GNU FreeFont Credits
+                         ====================
+
+This file lists contributors and contributions to the GNU FreeFont project.
+
+
+* URW++ Design & Development GmbH <http://www.urwpp.de/>
+
+URW++ donated a set of 35 core PostScript Type 1 fonts to the
+Ghostscript project <http://www.ghostscript.com/>, to be available
+under the terms of GNU General Public License (GPL).
+
+	Basic Latin				(U+0041-U+007A)
+	Latin-1 Supplement                      (U+00C0-U+00FF)
+	Latin Extended-A                        (U+0100-U+017F)
+	Spacing Modifier Letters		(U+02B0-U+02FF)
+	Mathematical Operators			(U+2200-U+22FF)
+	Block Elements				(U+2580-U+259F)
+	Dingbats				(U+2700-U+27BF)
+
+
+* Yannis Haralambous <yannis.haralambous AT enst-bretagne.fr> and John
+  Plaice <plaice AT omega.cse.unsw.edu.au>
+
+Yannis Haralambous and John Plaice are the authors of Omega typesetting
+system, <http://omega.enstb.org/>. Omega is an extension of TeX.
+Its first release, aims primarily at improving TeX's multilingual abilities.
+In Omega all characters and pointers into data-structures are 16-bit wide,
+instead of 8-bit, thereby eliminating many of the trivial limitations of TeX.
+Omega also allows multiple input and output character sets, and uses
+programmable filters to translate from one encoding to another, to perform
+contextual analysis, etc. Internally, Omega uses the universal 16-bit Unicode
+standard character set, based on ISO-10646. These improvements not only make
+it a lot easier for TeX users to cope with multiple or complex languages,
+like Arabic, Indic, Khmer, Chinese, Japanese or Korean, in one document, but
+will also form the basis for future developments in other areas, such as
+native color support and hypertext features. ... Fonts for UT1 (omlgc family)
+and UT2 (omah family) are under development: these fonts are in PostScript
+format and visually close to Times and Helvetica font families. 
+Omega fonts are available subject to GPL
+
+	Latin Extended-B                        (U+0180-U+024F)
+	IPA Extensions				(U+0250-U+02AF)
+	Greek					(U+0370-U+03FF)
+	Armenian				(U+0530-U+058F)
+	Hebrew					(U+0590-U+05FF)
+	Arabic					(U+0600-U+06FF)
+	Currency Symbols			(U+20A0-U+20CF)
+	Arabic Presentation Forms-A		(U+FB50-U+FDFF)
+	Arabic Presentation Forms-B		(U+FE70-U+FEFF)
+
+Current info: <http://tug.ctan.org/cgi-bin/ctanPackageInformation.py?id=omega>
+
+* Valek Filippov <frob AT df.ru>
+
+Valek Filippov added Cyrillic glyphs and composite Latin Extended A to
+the whole set of the abovementioned URW set of 35 PostScript core fonts,
+<ftp://ftp.gnome.ru/fonts/>.  The fonts are available under GPL.
+(The Cyrillic range was since replaced by another font.)
+
+	Latin Extended-A                        (U+0100-U+017F)
+
+
+* Wadalab Kanji Comittee
+
+Between April 1990 and March 1992, Wadalab Kanji Comittee put together a
+series of scalable font files with Japanese scripts, in four forms:
+Sai Micho, Chu Mincho, Cho Kaku and Saimaru.
+The font files are written in custom file format, while tools for conversion
+into Metafont and PostScript Type 1 are also supplied. The Wadalab Kanji
+Comittee was later dismissed. The resulting files were once found on the FTP
+server of the Department of Mathematical Engineering and Information Physics,
+Faculty of Engineering, University of Tokyo.  Some of these are available at
+<http://www.ctan.org/tex-archive/fonts/wadalab>
+
+	Hiragana				(U+3040-U+309F)
+	Katakana				(U+30A0-U+30FF)
+
+
+* Young U. Ryu <ryoung AT utdallas.edu>
+
+Young Ryu is the author of Txfonts, a set of mathematical symbols
+designed to accompany text typeset in Times or its variants. In the
+documentation, Young adresses the design of mathematical symbols: "The
+Adobe Times fonts are thicker than the CM fonts. Designing math fonts
+for Times based on the rule thickness of Times = , , + , / , < ,
+etc. would result in too thick math symbols, in my opinion. In the TX
+fonts, these glyphs are thinner than those of original Times
+fonts. That is, the rule thickness of these glyphs is around 85% of
+that of the Times fonts, but still thicker than that of the CM fonts."
+TX fonts are are distributed under the GNU public license (GPL). 
+<http://www.ctan.org/tex-archive/fonts/txfonts/>.
+
+	Arrows					(U+2190-U+21FF)
+	Mathematical Symbols			(U+2200-U+22FF)
+
+
+* Angelo Haritsis <ah AT computer.org>
+
+Angelo Haritsis has compiled a set of Greek Type 1 fonts, once available as
+as a tarball named greekXfonts-Type1-1.1.tgz.
+The glyphs from this source have been used to compose Greek glyphs in
+FreeSans and FreeMono.
+
+Angelo's licence says: "You can enjoy free use of these fonts for
+educational or commercial purposes.  All derived works should include
+this paragraph.  If you want to change something please let me have
+your changes (via email) so that they can go into the next
+version. You can also send comments etc to the above address."
+
+	Greek					(U+0370-U+03FF)
+
+
+* Yannis Haralambous and Virach Sornlertlamvanich
+
+In 1999, Yannis Haralambous and Virach Sornlertlamvanich made a set of
+glyphs covering the Thai national standard Nf3, in both upright and
+slanted shape. The collection of glyphs have been made part of GNU
+intlfonts 1.2 package and is available under the GPL at
+<ftp://ftp.gnu.org/pub/gnu/intlfonts/>.
+
+	Thai					(U+0E00-U+0E7F)
+
+* Shaheed R. Haque <srhaque AT iee.org>
+
+Shaheed Haque has developed a basic set of basic Bengali glyphs
+(without ligatures), using ISO10646 encoding. They are available under
+the XFree86 license at <http://www.btinternet.com/~shaheedhaque/>.
+
+Copyright (C) 2001 S.R.Haque <srhaque AT iee.org>.  All Rights Reserved.
+
+Permission is hereby granted, free of charge, to any person obtaining
+a copy of this software and associated documentation files (the
+"Software"), to deal in the Software without restriction, including
+without limitation the rights to use, copy, modify, merge, publish,
+distribute, sublicense, and/or sell copies of the Software, and to
+permit persons to whom the Software is furnished to do so, subject to
+the following conditions:
+
+The above copyright notice and this permission notice shall be
+included in all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
+IN NO EVENT SHALL S.R.HAQUE BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
+ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+OTHER DEALINGS IN THE SOFTWARE.
+
+Except as contained in this notice, the name of S.R.Haque shall not be
+used in advertising or otherwise to promote the sale, use or other
+dealings in this Software without prior written authorization from
+S.R.Haque.
+
+	Bengali					(U+0980-U+09FF)
+
+
+* Sam Stepanyan <sam AT arminco.com>
+
+Sam Stepanyan created a set of Armenian sans serif glyphs visually
+compatible with Helvetica or Arial. Available on
+<http://www.editum.com.ar/mashtots/html/fonts/ara.tar.gz>. On
+2002-01-24, Sam writes: "Arial Armenian font is free for
+non-commercial use, so it is OK to use under GPL license."
+
+Armenian				(U+0530-U+058F)
+
+
+* Mohamed Ishan <>
+
+Mohamed Ishan started the Thaana Unicode Project and among other things
+created a couple of Thaana fonts, available under FDL or BDF license.
+
+	Thaana					(U+0780-U+07BF)
+
+
+* Sushant Kumar Dash <sushant AT writeme.com> (*)
+
+Sushant Dash has created a font in his mother tongue, Oriya. As he
+states on his web page <http://sushantdash.tripod.com/>:
+"Please feel free to foreword this mail to your Oriya friends. No
+copyright law is applied for this font. It is totally free!!! Feel
+free to modify this using any font editing tools. This is designed for
+people like me, who are away from Orissa and want to write letters
+home using Computers, but suffer due to unavailability of Oriya
+fonts.(Or the cost of the available packages are too much)."
+
+	Oriya					(U+0B00-U+0B7F)
+
+
+* Harsh Kumar <harshkumar AT vsnl.com>
+
+Harsh Kumar has started BharatBhasha <http://www.bharatbhasha.net/> -
+an effort to provide "FREE software, Tutorial, Source Codes
+etc. available for working in Hindi, Marathi, Gujarati, Gurmukhi and
+Bangla. You can type text, write Web pages or develop Indian Languages
+Applications on Windows and on Linux. We also offer FREE help to
+users, enthusiasts and software developers for their work in Indian
+languages."
+
+	Devanagari				(U+0900-U+097F)
+	Bengali					(U+0980-U+09FF)
+	Gurmukhi				(U+0A00-U+0A7F)
+	Gujarati				(U+0A80-U+0AFF)
+
+
+* Prasad A. Chodavarapu <chprasad AT hotmail.com>
+
+Prasad A. Chodavarapu created Tikkana, a Telugu font available in Type
+1 and TrueType format on <http://chaitanya.bhaavana.net/fonts/>. 
+Tikkana exceeds the Unicode Telugu range with some composite glyphs.
+Available under the GNU General Public License.
+
+	Telugu					(U+0C00-U+0C7F)
+
+
+* Frans Velthuis <velthuis AT rc.rug.nl> and Anshuman Pandey
+  <apandey AT u.washington.edu>
+
+In 1991, Frans Velthuis from the Groningen University, The Netherlands,
+released a Devanagari font as Metafont source, available under the terms of
+GNU GPL. Later, Anshuman Pandey from the Washington University, Seattle, USA,
+took over the maintenance of font.  Zdeněk Wagner has provided a huge amount
+of expert advice regarding the implementation of the font in FreeSerif.
+Fonts can be found on CTAN,
+<ftp://ftp.dante.de/tex-archive/language/devanagari/>.
+
+	Devanagari				(U+0900-U+097F)
+
+
+* Hardip Singh Pannu <HSPannu AT aol.com>
+
+In 1991, Hardip Singh Pannu has created a free Gurmukhi TrueType font,
+available as regular, bold, oblique and bold oblique form. Its license
+says "Please remember that these fonts are copyrighted (by me) and are
+for non-profit use only." 
+
+	Gurmukhi				(U+0A00-U+0A7F)
+
+
+* Jeroen Hellingman <jehe AT kabelfoon.nl>
+
+Jeroen Hellingman created a set of Malayalam metafonts in 1994, and a
+set of Oriya metafonts in 1996. Malayalam fonts were created as
+uniform stroke only, while Oriya metafonts exist in both uniform and
+modulated stroke. From private communication: "It is my intention to
+release the fonts under GPL, but not all copies around have this
+notice on them." Metafonts can be found on CTAN,
+<ftp://ftp.dante.de/tex-archive/language/oriya/> and
+<ftp://ftp.dante.de/tex-archive/language/malayalam/>.
+
+	Oriya					(U+0B00-U+0B7F)
+	Malayalam				(U+0D00-U+0D7F)
+
+
+* Thomas Ridgeway <> (*)
+
+Thomas Ridgeway, then at the Humanities And Arts Computing Center,
+Washington University, Seattle, USA, (now defunct), created a Tamil
+metafont in 1990. Anshuman Pandey from the same university took over
+the maintenance of font. Fonts can be found at CTAN,
+<ftp://ftp.dante.de/tex-archive/language/tamil/wntamil/>.
+
+	Tamil					(U+0B80-U+0BFF)
+
+
+* Berhanu Beyene <1beyene AT informatik.uni-hamburg.de>,
+  Prof. Dr. Manfred Kudlek <kudlek AT informatik.uni-hamburg.de>, Olaf
+  Kummer <kummer AT informatik.uni-hamburg.de>, and Jochen Metzinger <?>
+
+Beyene, Kudlek, Kummer and Metzinger from the Theoretical Foundations
+of Computer Science, University of Hamburg, prepared a set of Ethiopic
+metafonts, found on
+<ftp://ftp.dante.de/tex-archive/language/ethiopia/ethiop/>. They also
+maintain home page on the Ethiopic font project,
+<http://www.informatik.uni-hamburg.de/TGI/mitarbeiter/wimis/kummer/ethiop_eng.html>,
+and can be reached at <ethiop AT informatik.uni-hamburg.de>. The current
+version of fonts is 0.7 (1998), and they are released under GNU GPL. I
+converted the fonts to Type 1 format using Péter Szabó's TeXtrace-A
+program <http://www.inf.bme.hu/~pts/textrace/> and removed some
+redundant control points with PfaEdit.
+
+	Ethiopic				(U+1200-U+137F)
+
+
+* Maxim Iorsh <iorsh AT users.sourceforge.net>
+
+In 2002, Maxim Iorsh started the Culmus project, aiming at providing
+Hebrew-speaking Linux and Unix community with a basic collection of
+Hebrew fonts for X Windows. The fonts are visually compatible with
+URW++ Century Schoolbook L, URW++ Nimbus Sans L and URW++ Nimbus Mono
+L families, respectively, and are released under GNU GPL license. See
+also <http://culmus.sourceforge.net/>.
+
+	Hebrew					(U+0590-U+05FF)
+
+
+* Panayotis Katsaloulis <panayotis AT panayotis.com>
+
+Panayotis Katsaloulis helped fixing Greek accents in the Greek
+Extended area.
+
+	Greek Extended				(U+1F00-U+1FFF)
+
+
+* Vyacheslav Dikonov <sdiconov AT mail.ru>
+
+Vyacheslav Dikonov made a Braille unicode font that could be merged
+with the UCS fonts to fill the 2800-28FF range completely. (uniform
+scaling is possible to adapt it to any cell size). He also contributed
+a free syriac font, whose glyphs (about half of them) are borrowed
+from the "Carlo Ator" font by Tim Erickson.
+Vyacheslav also filled in a few missing
+spots in the U+2000-U+27FF area, e.g. the box drawing section, sets of
+subscript and superscript digits and capital Roman numbers.
+
+	Syriac					(U+0700-U+074A)
+	Box Drawing				(U+2500-U+257F)
+	Braille					(U+2800-U+28FF)
+
+* Tim Erickson
+
+Is the author of several Eurasian fonts, including "Carlo Ator".
+He has given his written permission for glyphs from this font to be
+included in FreeFont.
+	Syriac					(U+0700-U+074A)
+
+
+* M.S. Sridhar <mssridhar AT vsnl.com>
+
+M/S Cyberscape Multimedia Limited, Mumbai, developers of Akruti
+Software for Indian Languages (http://www.akruti.com/), have released
+a set of TTF fonts for nine Indian scripts (Devanagari, Gujarati,
+Telugu, Tamil, Malayalam, Kannada, Bengali, Oriya, and Gurumukhi)
+under the GNU General Public License (GPL). You can download the fonts
+from the Free Software Foundation of India WWW site
+(http://www.gnu.org.in/akruti-fonts/) or from the Akruti website.
+
+For any further information or assistance regarding these fonts,
+please contact mssridhar AT vsnl.com.
+
+	Devanagari				(U+0900-U+097F)
+	Bengali					(U+0980-U+09FF)
+	Gurmukhi				(U+0A00-U+0A7F)
+	Gujarati				(U+0A80-U+0AFF)
+	Oriya					(U+0B00-U+0B7F)
+	Tamil					(U+0B80-U+0BFF)
+	Telugu					(U+0C00-U+0C7F)
+	Kannada					(U+0C80-U+0CFF)	
+	Malayalam				(U+0D00-U+0D7F)
+
+
+* DMS Electronics, The Sri Lanka Tipitaka Project, and Noah Levitt
+  <nlevitt AT columbia.edu>
+
+Noah Levitt found out that the Sinhalese fonts available on the site
+<http://www.metta.lk/fonts/> are released under GNU GPL, or,
+precisely, "Public Domain under GNU Licence
 Produced by DMS
+Electronics for The Sri Lanka Tipitaka Project" (taken from the font
+comment), and took the effort of recoding the font to Unicode.
+
+These glyphs were later replaced by those from the LKLUG font
+<http://www.lug.lk/fonts/lklug>
+
+Finally the range was completely replaced by glyphs from the sinh TeX
+font, with much help and advice from Harshula Jayasuriya.
+
+	Sinhala					(U+0D80-U+0DFF)
+       
+
+* Daniel Shurovich Chirkov <dansh AT chirkov.com>
+
+Dan Chirkov updated the FreeSerif font with the missing Cyrillic
+glyphs needed for conformance to Unicode 3.2. The effort is part of
+the Slavjanskij package for Mac OS X,
+<http://www.versiontracker.com/dyn/moreinfo/macosx/18680>.
+
+	Cyrillic				(U+0400-U+04FF)
+
+
+* Denis Jacquerye <moyogo AT gmail.com>
+
+Denis Jacquerye added new glyphs and corrected existing ones in the
+Latin Extended-B and IPA Extensions ranges.
+
+	Latin Extended-B                        (U+0180-U+024F)
+	IPA Extensions				(U+0250-U+02AF)
+
+
+* K.H. Hussain <hussain AT kfri.org> and R. Chitrajan
+
+`Rachana' in Malayalam means `to write', `to create'. Rachana Akshara Vedi,
+a team of socially committed information technology professionals and
+philologists, has applied developments in computer technology and desktop
+publishing to resurrect the Malayalam language from the disorder,
+fragmentation and degeneration it had suffered since the attempt to adapt
+the Malayalam script for using with a regular mechanical typewriter, which
+took place in 1967-69. K.H. Hussein at the Kerala Forest Research Institute
+has released "Rachana Normal" fonts with approximately 900 glyphs required
+to typeset traditional Malayalam. R. Chitrajan apparently encoded the
+glyphs in the OpenType table.
+
+In 2008, the Malayalam ranges in FreeSerif were updated under the advise 
+and supervision of Hiran Venugopalan of Swathanthra Malayalam Computing,
+to reflect the revised edition Rachana_04.
+
+	Malayalam				(U+0D00-U+0D7F)
+
+
+* Solaiman Karim <solaiman AT ekushey.org>
+
+	Bengali					(U+0980-U+09FF)
+
+Solaiman Karim has developed several OpenType Bangla fonts and
+released them under GNU GPL on <http://www.ekushey.org>.
+
+
+* Sonali Sonania <sonalisonania AT gmail.com> and Monika Shah
+  <monikapatira AT gmail.com>
+
+	Devanagari				(U+0900-U+097F)
+	Gujarati				(U+0A80-U+0AFF)
+
+Glyphs were drawn by Cyberscape Multimedia Ltd., #101,Mahalakshmi
+Mansion 21st Main 22nd "A" Cross Banashankari 2nd stage Banglore
+560070, India. Converted to OTF by IndicTrans Team, Powai, Mumbai,
+lead by Prof. Jitendra Shah. Maintained by Monika Shah and Sonali
+Sonania of janabhaaratii Team, C-DAC, Mumbai. This font is released
+under GPL by Dr. Alka Irani and Prof Jitendra Shah, janabhaaratii
+Team, C-DAC, Mumabi. janabhaaratii is localisation project at C-DAC
+Mumbai (formerly National Centre for Software Technology); funded by
+TDIL, Govt. of India. Contact:monika_shah AT lycos.com,
+sonalisonania AT yahoo.com, jitendras AT vsnl.com, alka AT ncst.ernet.in.
+website: www.janabhaaratii.org.in.
+
+
+* Pravin Satpute <pravin.d.s AT gmail.com>, Bageshri Salvi
+  <sbagrshri AT yahoo.co.in>, Rahul Bhalerao <b.rahul.pm AT
+  gmail.com> and Sandeep Shedmake <sandeep.shedmake AT gmail.com>
+
+	Devanagari				(U+0900-U+097F)
+	Gujarati				(U+0A80-U+0AFF)
+	Oriya					(U+0B00-U+0B7F)
+	Malayalam				(U+0D00-U+0D7F)
+	Tamil					(U+0B80-U+0BFF)
+
+In December 2005 the team at www.gnowledge.org released a set of two
+Unicode pan-Indic fonts: "Samyak" and "Samyak Sans". "Samyak" font
+belongs to serif style and is an original work of the team; "Samyak
+Sans" font belongs to sans serif style and is actually a compilation
+of already released Indic fonts (Gargi, Padma, Mukti, Utkal, Akruti
+and ThendralUni). Both fonts are based on Unicode standard. 
+The fonts are now hosted at Sarovar.org:
+http://sarovar.org/projects/samyak/
+
+
+* Kulbir Singh Thind
+
+	Gurmukhi				(U+0A00-U+0A7F)
+
+Dr. Kulbir Singh Thind designed a set of Gurmukhi Unicode fonts,
+AnmolUni and AnmolUni-Bold, which are available under the terms of GNU
+Generel Public License from the Punjabu Computing Resource Center,
+http://guca.sourceforge.net/typography/fonts/anmoluni/.
+
+
+* Gia Shervashidze <giasher AT telenet.ge>
+
+        Georgian				(U+10A0-U+10FF)
+
+Starting in mid-1990s, Gia Shervashidze designed many
+Unicode-compliant Georgian fonts: Times New Roman Georgian, Arial
+Georgian, Courier New Georgian. His work on Georgian localization can
+be reached at http://www.gia.ge/.
+
+
+* Primož Peterlin <primoz.peterlin AT biofiz.mf.uni-lj.si>
+
+Primož Peterlin filled in missing glyphs here and there (e.g. Latin
+Extended-B and IPA Extensions ranges in the FreeMono familiy), and
+created the following UCS blocks:
+
+	Latin Extended-B                        (U+0180-U+024F)
+	IPA Extensions				(U+0250-U+02AF)
+	Arrows					(U+2190-U+21FF)
+	Box Drawing				(U+2500-U+257F)
+	Block Elements				(U+2580-U+259F)
+	Geometrical Shapes			(U+25A0-U+25FF)
+
+* Mark Williamson
+
+Made the MPH 2 Damase font, from which 
+	Hanunóo                                 (U+1720-U+173F)
+	Buginese                                (U+1A00-U+1A1F)
+	Tai Le                                  (U+1950-U+197F)
+	Ugaritic                                (U+10380-U+1039F)
+	Old Persian                             (U+103A0-U+103DF)
+
+* Jacob Poon
+
+Submitted a very thorough survey of glyph problems and other suggestions.
+
+* Alexey Kryukov
+
+Made the TemporaLCGUni fonts, based on the URW++ fonts, from which at one 
+point FreeSerif Cyrillic, and some of the Greek, was drawn.  He also provided
+valuable direction about Cyrillic and Greek typesetting.
+
+	Cyrillic				(U+0400-U+04FF)
+
+* George Douros
+
+The creator of several fonts focusing on ancient scripts and symbols.
+Many of the glyphs are created by making outlines from scanned images
+of ancient sources.
+
+	Aegean:   Phoenecian
+	Analecta: Gothic                        (U+10330-U+1034F)
+	Musical:  Byzantine & Western                  
+	Unicode:  many Miscellaneous Symbols, Miscellaneous Technical, OCR,
+	          supplemental Symbols, and Mathematical Alphanumeric symbols,
+		  Mah Jong, and the outline of the Domino.
+
+* Daniel Johnson
+
+Created by hand a Cherokee range specially for FreeFont to be "in line with
+the classic Cherokee typefaces used in 19th century printing", but also to
+fit well with ranges previously in FreeFont.  Then he made Unified Canadian
+Syllabics in Sans, and a Cherokee and Kayah Li in Mono!  And never to be
+outdone by himself, then did UCAS Extended and Osmanya....  What next?
+
+	Armenian (serif)                        (U+0530-U+058F)
+	Cherokee                                (U+13A0-U+13FF)
+	Unified Canadian Aboriginal Syllabics   (U+1400-U+167F)
+	UCAS Extended                           (U+18B0-U+18F5)
+	Kayah Li                                (U+A900-U+A92F)
+	Tifinagh                                (U+2D30-U+2D7F)
+	Vai                                     (U+A500-U+A62B)
+	Latin Extended-D (Mayanist letters)     (U+A720-U+A7FF)
+	Osmanya                                 (U+10480-U+104a7)
+
+* Yannis Haralambous and Wellcome Institute
+
+In 1994, The Wellcome Library
+  The Wellcome Institute for the History of Medicine
+  183 Euston Road, London NW1 2BE, England.
+commissioned Mr. Haralambous to produce a Sinhalese font for them.
+
+We have received 03/09 official notice from Robert Kiley, Head of e-Strategy
+for the Wellcome Library, that Yannis' font could be included in GNU
+FreeFont under its GNU license.
+
+Thanks to Dominik Wujastyk, for providing us with feedback and contacts
+to repsonsible people at the Trust.
+
+	Sinhala					(U+0D80-U+0DFF)
+
+* The Sinhala font project http://sinhala.sourceforge.net/
+
+The Sinhala font project has taken the glyphs from Yannis Haralambous'
+Sinhala font, to produce a Unicode TrueType font, LKLUG.  These glyphs
+were for a while included in FreeFont.
+
+	Sinhala					(U+0D80-U+0DFF)
+
+* Steve White <stevan.white AT googlemail.com>
+
+Filled in a lot of missing characters, got some font features working,
+left fingerprints almost everywhere, and is responsible for these blocks:
+
+	Runic                                   (U+16A0-U+16F0)
+	Glagolitic                              (U+2C00-U+2C5F)
+	Coptic                                  (U+2C80-U+2CFF)
+	Old Italic                              (U+10300-U+1032F)
+(The design of Runic is based roughly on one originally submitted by 
+Vyacheslav Dikonov)
+
+
+* Pavel Skrylev is responsible for
+	Cyrillic Extended-A                     (U+2DEO-U+2DFF)
+  as well as many of the additions to
+	Cyrillic Extended-B                     (U+A640-U+A65F)
+
+
+* Masoud Pourmoosa corrected several letters in Arabic for Persian:
+	Arabic					(U+0600-U+06FF)
+
+Notes:
+
+*: The glyph collection looks license-compatible, but its author has
+   not yet replied and agreed on their work being used in part of
+   this glyph collection.
+
+--------------------------------------------------------------------------
+$Id: CREDITS,v 1.28 2010/09/11 13:24:11 Stevan_White Exp $

games/Ping-Pong/res/fonts/freefont/INSTALL

@@ -0,0 +1,98 @@
+                          Installing GNU FreeFont
+                          =======================
+
+GNU FreeFont can be used in any modern operating system.
+
+This document explains how to install FreeFont on some common systems.
+
+UNIX/GNU/Linux/BSD Systems
+--------------------------
+
+FreeFont works with any system using the free font rasterizer FreeType
+<http://www.freetype.org/>.  Some features such as glyph substitution and
+positioning may be handled by the text layout library
+Pango <http://www.pango.org/>.
+
+Most recent systems using FreeType2 and Pango handle OpenType fonts well,
+but on older systems TrueType may perform better.
+
+* Debian GNU/Linux
+
+Users of Debian GNU/Linux system will probably want to use the Debian package,
+named 'ttf-freefont', available from the Debian Linux site.
+
+Install the fonts by issuing the command
+	apt-get install ttf-freefont
+
+
+* KDE local installation
+
+Users of KDE can install .ttf files on a per-user basis using the KDE 
+Control Center module "kcmfontinst", which may appear in the menu as
+
+	Settings -> System Administration -> Font Installer
+
+This is especially helpful for developers and testers.
+
+
+* Generic X Window systems
+
+	1) Fetch the freefont-ttf.tar.gz package with Free UCS outline fonts
+	   in the TrueType format.
+
+	2) Unpack TrueType fonts into a suitable directory,
+	   e.g. /usr/local/share/fonts/default/TrueType/
+
+	3) If you have chosen any other directory, make sure the directory you
+	   used to install the fonts is listed in the path searched by the X
+	   Font Server by editing the config file in /etc/X11/.
+
+	   In some systems, you list the directory in the item "catalogue="
+	   in the file /etc/X11/fs/config.
+
+	4) Run ttmkfdir in the directory where you unpacked the fonts.
+
+
+Microsoft Windows 95/98/NT/2000/XP; Vista/7
+-------------------------------------------
+
+Note that in at least Windows 7, Vista, XP and 2000, the TrueType versions
+perform much better than, and are recommended over, the OpenType ones.
+
+For good font smoothing in Windows, Microsoft ClearType must be enabled.
+The native Windows web browser must be used to install, enable, and configure
+ClearType. A web search for "ClearType Tuner" will find the proper web pages.
+Recent versions of the browser raise a security block (a yellow bar at the
+top of the window), which you must act upon to allow installation.  A
+checkbox in the window turns ClearType on (in Win-speek, "Turn on ClearType").
+The change happens immediately.
+
+* Vista, Windows 7:
+	1) From the Start menu, open Control Panels
+	2) Drag-n-drop font files onto Fonts control panel
+           You may get a dialog saying
+        	"Windows needs your permission to continue"
+	   a) Click Continue
+
+* 95/98/NT:
+	The font installation is similar to Vista.
+
+	In order to use OpenType, users of Windows 95, 98 and NT 4.0 can
+	install Adobe's 'Type Manager Light', which may be obtained from
+	the Adobe web site.
+
+	Otherwise, use the TrueType versions.
+
+Apple Mac OS X
+--------------
+
+Support for OpenType on MacOS X started with OS 10.4, and has been improved
+gradually in later versions.
+
+Installing on Mac OS X consists of moving the font files to either
+	/Library/Fonts/  or  ~/Library/Fonts/
+depending on whether they should be available to all users on your system
+or just to your own user.
+
+--------------------------------------------------------------------------
+$Id: INSTALL,v 1.11 2011-06-12 07:14:12 Stevan_White Exp $

games/Ping-Pong/res/fonts/freefont/README

@@ -0,0 +1,127 @@
+-*-text-*-
+                          GNU FreeFont
+
+The GNU FreeFont project aims to provide a useful set of free scalable
+(i.e., OpenType) fonts covering as much as possible of the ISO 10646/Unicode
+UCS (Universal Character Set).
+
+Statement of Purpose
+--------------------
+
+The practical reason for putting glyphs together in a single font face is
+to conveniently mix symbols and characters from different writing systems,
+without having to switch fonts.
+
+Coverage
+--------
+
+FreeFont covers the following character ranges
+* Latin, Cyrillic, and Arabic, with supplements for many languages
+* Greek, Hebrew, Armenian, Georgian, Thaana, Syriac
+* Devanagari, Bengali, Gujarati, Gurmukhi, Sinhala, Tamil, Malayalam
+* Thai, Tai Le, Kayah Li, Hanunóo, Buginese
+* Cherokee, Unified Canadian Aboriginal Syllabics
+* Ethiopian, Tifnagh, Vai, Osmanya, Coptic
+* Glagolitic, Gothic, Runic, Ugaritic, Old Persian, Phoenician, Old Italic
+* Braille, International Phonetic Alphabet
+* currency symbols, general punctuation and diacritical marks, dingbats
+* mathematical symbols, including much of the TeX repertoire of symbols
+* technical symbols: APL, OCR, arrows,
+* geometrical shapes, box drawing
+* musical symbols, gaming symbols, miscellaneous symbols
+  etc.
+For more detail see <http://www.gnu.org/software/freefont/coverage.html>
+
+Editing
+-------
+
+The free outline font editor, George Williams' FontForge
+<http://fontforge.sourceforge.net/> is used for editing the fonts.
+
+Design Issues
+-------------
+
+Which font shapes should be made?  Historical style terms like Renaissance
+or Baroque letterforms cannot be applied beyond Latin/Cyrillic/Greek
+scripts to any greater extent than Kufi or Nashki can be applied beyond
+Arabic script; "italic" is strictly meaningful only for Latin letters, 
+although many scripts such as Cyrillic have a history with "cursive" and
+many others with "oblique" faces. 
+
+However, most modern writing systems have typographic formulations for
+contrasting uniform and modulated character stroke widths, and since the
+advent of the typewriter, most have developed a typographic style with
+uniform-width characters.
+
+Accordingly, the FreeFont family has one monospaced - FreeMono - and two
+proportional faces (one with uniform stroke - FreeSans - and one with
+modulated stroke - FreeSerif).
+
+The point of having characters from different writing systems in one font
+is that mixed text should look good, and so each FreeFont face contains
+characters of similar style and weight.
+
+Licensing
+---------
+
+Free UCS scalable fonts is free software; you can redistribute it and/or
+modify it under the terms of the GNU General Public License as published
+by the Free Software Foundation; either version 3 of the License, or
+(at your option) any later version.
+
+The fonts are distributed in the hope that they will be useful, but
+WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+for more details.
+
+You should have received a copy of the GNU General Public License along
+with this program; if not, write to the Free Software Foundation, Inc.,
+51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+
+As a special exception, if you create a document which uses this font, and
+embed this font or unaltered portions of this font into the document, this
+font does not by itself cause the resulting document to be covered by the
+GNU General Public License. This exception does not however invalidate any
+other reasons why the document might be covered by the GNU General Public
+License. If you modify this font, you may extend this exception to your
+version of the font, but you are not obligated to do so.  If you do not
+wish to do so, delete this exception statement from your version.
+
+Files and their suffixes
+------------------------
+
+The files with .sfd (Spline Font Database) are in FontForge's native format. 
+They may be used to modify the fonts.
+
+TrueType fonts are the files with the .ttf (TrueType Font) suffix.  These
+are ready to use in Linux/Unix, on Apple Mac OS, and on Microsoft Windows
+systems.
+
+OpenType fonts (with suffix .otf) are preferred for use on Linux/Unix,
+but *not* for recent Microsoft Windows systems.
+See the INSTALL file for more information.
+
+Web Open Font Format files (with suffix .woff) are for use in Web sites.
+See the webfont_guidelines.txt for further information.
+
+Further information
+-------------------
+
+Home page of GNU FreeFont:
+	http://www.gnu.org/software/freefont/
+
+More information is at the main project page of Free UCS scalable fonts:
+	http://savannah.gnu.org/projects/freefont/
+
+To report problems with GNU FreeFont, it is best to obtain a Savannah
+account and post reports using that account on
+	https://savannah.gnu.org/bugs/
+	
+Public discussions about GNU FreeFont may be posted to the mailing list
+	freefont-bugs@gnu.org
+
+--------------------------------------------------------------------------
+Original author: Primoz Peterlin
+Current administrator: Steve White <stevan.white@googlemail.com>
+
+$Id: README,v 1.10 2011-06-12 07:14:12 Stevan_White Exp $

games/Ping-Pong/res/fonts/freefont/TROUBLESHOOTING

@@ -0,0 +1,115 @@
+	Troubleshooting GNU FreeFont
+
+So your text looks lousy, although you installed FreeFont and you seem to be
+using it.  What do you do?
+
+Before you blame the problem on FreeFont, take the time to double-check that
+the text you are looking at is really rendered with FreeFont.
+
+Be aware that not all Unicode characters are supported by FreeFont, and
+even characters supported by one face, such as Serif, might not be
+supported by other faces such as Sans.
+
+Also, some systems have settings that strongly affect the rendering
+of fonts.  It may be worth tweaking these.
+
+glyph substitution
+==================
+
+When given the task of displaying characters in text, modern font rendering
+software usually tries to display *something*, even if the font it is
+*supposed* to be using does not contain glyphs for all the characters in the
+text.  The software will snoop through all the fonts on the system to find
+one that has a glyph for the one missing in the desired font.  So although
+you have specified FreeSans-bold, you may be looking at a letter from quite
+a different font.
+
+First double-check that the font in question really contains the character
+in question.  If you don't have font development software, this can be
+tricky.  In the case of FreeFont, you can check if a given character 
+range is supported: <http://www.gnu.org/software/freefont/coverage.html>
+
+Next double-check that your application (web browser, text editor, etc)
+has indeed been properly instructed to use the font.
+
+Then double-check that the font is really installed in the system.
+(This depends on the operating system, of course.)
+
+Linux and Unix
+==============
+
+Modern Linux systems use a system called fontconfig, which maintains a font
+cache, for efficiency.
+
+The font cache can really complicate font installation and troubleshooting
+however.  It can happen that when a font is newly installed, what is 
+displayed is coming out of an old cache entry rather than the new font.
+
+Just what to do depends on how and where the font was installed.
+
+Fonts installed system-wide are usually put in a directory such as
+	/usr/share/fonts/
+the font cache for these might be in
+	/var/cache/fontconfig/
+Fonts installed just for one user account will typically be in
+	~/.fonts/
+and the cache will be
+	~/.fontconfig/
+
+You can clean your local cache merely by emptying the directory 
+	~/.fontconfig/
+In any case, to clean the cache, you can use the fontconfig command
+	fc-cache -vf
+If run as root, it will clean the system cache, if run as a normal user,
+it cleans only the normal user's cache.
+
+The procedure for local fonts is:
+	1) shut off any program using the fonts in question
+	2) clean the cache
+	3) re-start the program
+The procedure for system-wide fonts is:
+	1) log out of the X Windows session
+	2) in a console, clean the cache
+	3) log in to an X Windows session
+
+LibreOffice / OpenOffice
+========================
+These products have their own font rendering libraries, which have 
+idiosyncratic behavior.
+
+It has recently been reported that as of LibreOffice 3.5.1, font features
+are disabled for OpenType fonts.  If you use FreeFont with these products,
+you may want to install the TrueType versions of the fonts.
+
+Windows
+=======
+
+The most common complaint has to do with "blurry text".  There are two
+causes.
+
+The first is that ClearType smoothing is turned off.  The best way to check
+is to use the native Windows Web browser. Do a search for "ClearType Tuner".
+The Microsoft pages install a tuner for ClearType. A security block notice
+will appear at the top of the window--you have to allow the installation.
+Then check the box "Turn on ClearType".  The change happens immediately.
+
+The secont cause is that the FreeFont version with cubic spline outlines is
+installed.  As of the 2012 GNU FreeFont release, the TrueType builds have
+quadratic splines, which work best with Windows' rendering software.
+	TTF (TrueType)  quadratic splines Windows 7, Vista, Windows XP.
+	OTF (OpenType)  cubic splines     Linux, Mac
+
+Note also: Firefox has a setting for ClearType:
+	gfx.font_rendering.cleartype_params.rendering_mode
+A value of 2 sets it to old-style GDI rendering, while -1 is the default.
+
+reporting problems
+==================
+
+If you really think you're seeing a bug in FreeFont, or if you have
+a suggestion, consider opening a problem report at
+	https://savannah.gnu.org/bugs/?group=freefont
+It is best that you make a Savannah account and log in with that, so 
+you can be e-mailed whenever changes are made to your report.
+
+$Id: troubleshooting.txt,v 1.10 2011-07-16 08:38:06 Stevan_White Exp $

games/Ping-Pong/res/fonts/freefont/USAGE

@@ -0,0 +1,185 @@
+	Usage of GNU FreeFont
+
+Language scripts and faces
+==========================
+
+There are three faces (serif, sans-serif, and monospace), and four styles
+(regular, bold, cursive/italic, and bold cursive/italic) for each face.
+There is one font file per face/style combination: 12 files in total.
+
+The letters for various languages, as well as specialized symbols, exist
+among the various font files, but they are not uniformly populated.
+All the fonts have complete support for Latin, Cyrillic, and Greek, as
+well as most of the extensions for those scripts.
+
+At this time, serif regular has by far the largest number of letters, and
+supports the largest number of writing scripts.  However there are writing
+scripts supported by the sans-serif but not by serif.
+
+For an overview of which scripts and sets of symbols are supported by
+which face, see the FreeFont 'coverage' web page.
+
+Font features
+=============
+
+FreeFont has numerous font "features" that perform alterations to the basic
+letters of the font, replacing them with other letters, or positioning them
+with respect to other letters.
+
+Many features are activated automatically, but in some environments, they
+present some user control.  This documents those features with user control.
+
+Language-specific features
+==========================
+
+Some OpenType font features are activated only when the text is specified to
+be of a certain language. 
+
+This is done in HTML by enclosing the text with a tag whose 'lang' attribute
+is set to the appropriate ISO 632.2 language code.  In a word processor, 
+any block of text can be given a language setting.
+
+Latin
+-----
+Catalan	ligature improving l·l
+Dutch	ligatures for ij, IJ
+Sami	localized form for letter Eng
+Turkish	overrides ligatures fi ffi of Latin
+
+Cyrillic
+--------
+Ukrainian	ligature for double i-diaresis
+Serbian/Macedonian	localized letters be, and more in italic
+Bulgarian	style set for modern glyphs
+
+Hebrew
+------
+Yiddish	raised vowels under yo
+
+Devanagari
+----------
+Sanskrit	much larger set of ligatures
+
+Hindi, Marathi	better spacing of Western punctuation marks
+
+Indic languages
+---------------
+
+The 'danda' character is encoded in Unicode only in the Devanagari range.
+When writing in scripts of other Indic languages, this same character is to
+be used.  But the shapes and line thicknesses of glyphs vary slightly from
+one script to another, so the same glyph for 'danda' may not fit all scripts.
+
+By specifying the language of the text, an appropriate glyph for 'danda'
+will be obtained.
+
+Style sets
+==========
+
+These replacements are activated by specifying a "Style Set".
+These features are accessible only from typesetting software.
+
+Cyrillic	Bulgarian modern (ss01)
+
+Devanagari	Bombay (ss02), Calcutta (ss03), Nepali (ss04)
+
+Discretionary features
+======================
+These features are accessible only from typesetting software.
+Typically the user must specifically request them.
+
+Unless otherwise noted, these are available only in FreeSerif.
+
+Ligatures and substitutions
+---------------------------
+
+Arabic, Armenian, Hebrew, German, Dutch
+
+Small captials
+--------------
+
+A limited set of specially drawn small capital letters in Latin.
+
+Superscript and subscript
+-------------------------
+
+Transform a limited set of characters--mostly Latin letters and numerals--
+to versions well-sized and positioned as superscript or subscript.
+
+Numeral styles
+--------------
+
+The default numerals of FreeSerif are mono-spaced and of even height.
+It also features proportionally-spaced numerals, and "old-style" numerals--
+those which vary in height and sometimes go beneath the baseline.
+These can be had at discretion.
+
+Diagonal fractions
+------------------
+
+A limited set of diagonal fraction substitutions are available at discretion.
+The set is more than what is encoded in Unicode.
+They work with the ASCII slash or the mathematical slash U+2215.
+The transform a sequence "number-slash-number" to a diagonal form.
+
+Zero
+----
+
+A slashed form of the numeral zero is available at discretion.
+Available in all faces.
+
+Alternative characters
+======================
+
+FreeSerif has some listings of alternatives for specific characters.
+Again this is use primarily in specialized typesetting software.
+
+Greek, Latin
+
+Use in LaTeX
+============
+It is possible to use Unicode fonts in recent LaTeX implementations, but in
+	LuaTeX http://www.luatex.org/ and
+	XeTeX http://tug.org/xetex/
+it is particularly easy to use Unicode text, and to enable font features.
+Recent versions of these systems use the 'fontspec' package to choose fonts
+and features.
+
+A very simple document might contain the lines
+---------------------------------------------------------------------------
+\documentclass{ltxdockit}
+\usepackage{fontspec}
+\usepackage{xunicode}
+\setmainfont[]{FreeSerif}
+\begin{document}
+{\fontspec[Script=Default,Fractions={On}]{FreeSerif}
+1/7 3/10 7/10}
+
+x\raisebox{-0.5ex}{{\scriptsize ai}}
+x{\fontspec[Script=Default,VerticalPosition={Inferior}]{FreeSerif}
+abcdefghijklmnopqrstuvwxyz+−(0123456789)} \\
+x\raisebox{0.85ex}{{\scriptsize ai}}
+x{\fontspec[Script=Default,VerticalPosition={Superior}]{FreeSerif}
+abcdefghijklmnopqrstuvwxyz+−(0123456789)}
+
+{\fontspec[Script=Latin]{FreeSerif}
+\textsc{Small Caps} }
+
+{ Bсички хора се раждат свободни и равни по достойнство и права.
+\fontspec[Script=Cyrillic,Language=Bulgarian,Variant={1}]{FreeSerif} \selectfont
+Bсички хора се раждат свободни и равни по достойнство и права.  }
+
+\end{document}
+---------------------------------------------------------------------------
+Here are some 'fontspec' setting-value pairs meaningful for FreeFont.
+
+Numbers: Lining OldStyle Proportional SlashedZero
+Fractions: On
+VerticalPosition: Superior Inferior
+Ligatures: Common Historical
+Letters: UppercaseSmallCaps
+Variant: 1 (etc. -- must be in {} picks style set.)
+---------------------------------------------------------------------------
+
+
+$Id: usage.txt,v 1.10 2011-07-16 08:38:06 Stevan_White Exp $

games/Ping-Pong/res/fonts/manaspace/license.txt

@@ -0,0 +1,17 @@
+Thanks for downloading one of codeman38's retro video game fonts, as seen on Memepool, BoingBoing, and all around the blogosphere.
+
+So, you're wondering what the license is for these fonts? Pretty simple; it's based upon that used for Bitstream's Vera font set <http://www.gnome.org/fonts/>.
+
+Basically, here are the key points summarized, in as little legalese as possible; I hate reading license agreements as much as you probably do:
+
+With one specific exception, you have full permission to bundle these fonts in your own free or commercial projects-- and by projects, I'm referring to not just software but also electronic documents and print publications.
+
+So what's the exception? Simple: you can't re-sell these fonts in a commercial font collection. I've seen too many font CDs for sale in stores that are just a repackaging of thousands of freeware fonts found on the internet, and in my mind, that's quite a bit like highway robbery. Note that this *only* applies to products that are font collections in and of themselves; you may freely bundle these fonts with an operating system, application program, or the like.
+
+Feel free to modify these fonts and even to release the modified versions, as long as you change the original font names (to ensure consistency among people with the font installed) and as long as you give credit somewhere in the font file to codeman38 or zone38.net. I may even incorporate these changes into a later version of my fonts if you wish to send me the modifed fonts via e-mail.
+
+Also, feel free to mirror these fonts on your own site, as long as you make it reasonably clear that these fonts are not your own work. I'm not asking for much; linking to zone38.net or even just mentioning the nickname codeman38 should be enough.
+
+Well, that pretty much sums it up... so without further ado, install and enjoy these fonts from the golden age of video games.
+
+[ codeman38 | cody@zone38.net | http://www.zone38.net/ ]

games/Ping-Pong/src/main.cpp

@@ -0,0 +1,130 @@
+#include <vector>
+#include "../../../include/Birb2D.hpp"
+
+void StartGame();
+void QuitGame();
+bool gameRunning = true;
+Birb2D::RenderWindow window("Ping Pong", 1280, 720, 240);
+std::vector<Birb2D::Scene*> scenes;
+Birb2D::Scene mainMenuScene("Main menu", window, true);
+Birb2D::Scene pauseMenuScene("Pause menu", window, false, 2);
+Birb2D::Scene gameScene("Game scene", window, false);
+
+int main()
+{
+	Debug::Log("Starting pinging and ponging");
+
+	// Game loop
+	bool holdingKeyDown = false;
+
+	// Fonts
+	Birb2D::Font titleFont("../res/fonts/freefont/FreeMono.ttf", Colors::White, 64);
+	Birb2D::Font mainMenuButtonFont("../res/fonts/freefont/FreeMonoBold.ttf", Colors::White, 32);
+
+	// Entities
+	/* Main menu */
+	Birb2D::Widgets::Text title(window, Vector2f(50, 50), "Ping Pong", titleFont);
+
+	Birb2D::Widgets::Button playButton(window, Rect(50, 128, 150, 40), Colors::LightGray, "Play", mainMenuButtonFont, StartGame);
+	Birb2D::Widgets::Button quitButton(window, Rect(50, 200, 150, 40), Colors::LightGray, "Quit", mainMenuButtonFont, QuitGame);
+	mainMenuScene.AddButton({playButton, quitButton});
+	mainMenuScene.AddText(title);
+
+	/* Pause menu */
+	Birb2D::Widgets::Rectangle pauseMenuBackground(window, Rect(300, 200, 210, 350), Colors::White);
+	Birb2D::Widgets::Button pauseQuitButton(window, Rect(310, 210, 190, 40), Colors::LightGray, "Quit", mainMenuButtonFont, QuitGame, 1);
+	pauseMenuScene.AddRectangle(pauseMenuBackground);
+	pauseMenuScene.AddButton(pauseQuitButton);
+
+	/* Game view */
+	Birb2D::Widgets::Text scoreText(window, Vector2f(50, 50), "Score: 0 - 0", titleFont);
+	gameScene.AddText(scoreText);
+
+	// Add scenes to a list
+	scenes.push_back(&mainMenuScene);
+	scenes.push_back(&pauseMenuScene);
+	scenes.push_back(&gameScene);
+	
+
+	SDL_Event event;
+	while (gameRunning)
+	{
+		window.timestepStart();
+		while (window.timestepRunning())
+		{
+			while (SDL_PollEvent(&event) != 0)
+			{
+				window.handleBasicWindowEvents(event, &gameRunning);
+				for (int i = 0; i < scenes.size(); i++)
+					scenes[i]->PollButtonEvents(event);
+
+				switch (event.type)
+				{
+					// Handle window resizing
+					case (SDL_WINDOWEVENT):
+						if (event.window.event == SDL_WINDOWEVENT_RESIZED)
+							window.SetWindowSize(event.window.data1, event.window.data2);
+						break;
+
+					default:
+						break;
+				}
+
+				// Keyboard input
+				if (event.type == SDL_KEYDOWN && !holdingKeyDown)
+				{
+					holdingKeyDown = true;
+
+					switch (event.key.keysym.sym)
+					{
+						case (SDLK_ESCAPE):
+							if (gameScene.isEnabled())
+								pauseMenuScene.toggle();
+							break;
+
+						default:
+							break;
+					}
+				}
+				else if (event.type == SDL_KEYUP)
+				{
+					holdingKeyDown = false;
+				}
+			}
+
+			window.timestepStep();
+		}
+
+		window.timestepEnd();
+
+		/* ### Render stuff ### */
+		window.clear();
+
+		// Render scenes
+		for (int i = 0; i < scenes.size(); i++)
+			scenes[i]->Render();
+
+		window.display();
+		/* ### End of rendering stuff */
+	}
+
+	Debug::Log("Cleanup");
+	window.cleanUp();
+	Debug::Log("SDL_Quit()");
+	SDL_Quit();
+	Debug::Log("Game should be closed now");
+	return 0;
+}
+
+void StartGame()
+{
+	Debug::Log("Starting the game!");
+	mainMenuScene.disable();
+	gameScene.enable();
+}
+
+void QuitGame()
+{
+	gameRunning = false;
+	Debug::Log("Quiting the game...");
+}

include/Audio.hpp

@@ -0,0 +1,42 @@
+#pragma once
+#include <iostream>
+
+#include <SDL2/SDL.h>
+#include <SDL2/SDL_mixer.h>
+
+class Audio
+{
+public:
+	bool initAudio(int flags);
+};
+
+class SoundFile
+{
+public:
+	SoundFile(std::string p_filePath);
+	void play();
+	void free()
+	{
+		Mix_FreeChunk(sound);
+	}
+	bool isPlaying();
+private:
+	Mix_Chunk* sound;
+	std::string filePath;
+};
+
+class MusicFile
+{
+public:
+	MusicFile(std::string p_filePath);
+	void play();
+	void play(bool loop);
+	void free()
+	{
+		Mix_FreeMusic(music);
+	}
+	bool isPlaying();
+private:
+	Mix_Music* music;
+	std::string filePath;
+};

include/Birb2D.hpp

@@ -0,0 +1,11 @@
+#include "Audio.hpp"
+#include "Entity.hpp"
+#include "Events.hpp"
+#include "Font.hpp"
+#include "Logger.hpp"
+#include "Math.hpp"
+#include "RenderWindow.hpp"
+#include "Scene.hpp"
+#include "Utils.hpp"
+#include "Values.hpp"
+#include "Widgets.hpp"

include/Editor.hpp

@@ -0,0 +1 @@
+#pragma once