From 4f813935e3a81b46f509883dfdb5abe7737fb58a Mon Sep 17 00:00:00 2001
From: Vovanium <vovanium@protonmail.ch>
Date: Tue, 17 May 2022 13:14:30 +0300
Subject: [PATCH] + SDL surface / raster conversion

---
 examples/hello_world_sdl.adb                  |  7 +++++
 .../sdl/video-backends-sdl-surfaces.adb       | 30 +++++++++++++++++++
 .../sdl/video-backends-sdl-surfaces.ads       | 15 ++++++++++
 3 files changed, 52 insertions(+)
 create mode 100644 source/backends/sdl/video-backends-sdl-surfaces.adb

diff --git a/examples/hello_world_sdl.adb b/examples/hello_world_sdl.adb
index f0203f7..0b56381 100644
--- a/examples/hello_world_sdl.adb
+++ b/examples/hello_world_sdl.adb
@@ -1,3 +1,5 @@
+with Ada.Text_IO, Ada.Integer_Text_IO;
+use  Ada.Text_IO, Ada.Integer_Text_IO;
 with Interfaces.C;
 with Video.Backends.SDL.Windows;
 with Video.Backends.SDL.Surfaces;
@@ -15,5 +17,10 @@ begin
 	Width => Screen_Width, Height => Screen_Height);
 	Surf := Windows.Get_Window_Surface (Wnd);
 
+	Put (Integer (Surf.w)); Put (" × "); Put (Integer (Surf.h)); New_Line;
+	Put ("Pitch:           "); Put (Integer (Surf.pitch)); New_Line;
+	Put ("Bits per pixel:  "); Put (Integer (Surf.format.Bits_Per_Pixel)); New_Line;
+	Put ("Bytes per pixel: "); Put (Integer (Surf.format.Bytes_Per_Pixel)); New_Line;
+
 	Err := Message_Boxes.Show_Message_Box (Title => "Hello World", Message => "Greetz!");
 end Hello_World_SDL;
diff --git a/source/backends/sdl/video-backends-sdl-surfaces.adb b/source/backends/sdl/video-backends-sdl-surfaces.adb
new file mode 100644
index 0000000..edd8cda
--- /dev/null
+++ b/source/backends/sdl/video-backends-sdl-surfaces.adb
@@ -0,0 +1,30 @@
+with Interfaces.C.Pointers;
+with System.Storage_Elements;
+use  System.Storage_Elements;
+
+package body Video.Backends.SDL.Surfaces is
+
+	package body Raster_Conversions is
+
+		type Pixel_Array is array (Integer range <>) of Pixel;
+
+		procedure Copy (
+			Source : in     Raster;
+			Target : in out Surface)
+		is
+		begin
+			for Y in Source'Range (1) loop
+				declare
+					Line : Pixel_Array (Source'Range (2)) with
+						Import, Address => Target.Pixels
+						+ Storage_Offset (Y - Source'First (1));
+				begin
+					for X in Source'Range (2) loop
+						Line (X) := Source (Y, X);
+					end loop;
+				end;
+			end loop;
+		end;
+	end Raster_Conversions;
+
+end Video.Backends.SDL.Surfaces;
diff --git a/source/backends/sdl/video-backends-sdl-surfaces.ads b/source/backends/sdl/video-backends-sdl-surfaces.ads
index c1c9a10..0ef0f90 100644
--- a/source/backends/sdl/video-backends-sdl-surfaces.ads
+++ b/source/backends/sdl/video-backends-sdl-surfaces.ads
@@ -23,4 +23,19 @@ package Video.Backends.SDL.Surfaces is
 
 	type Surface_Access is access all Surface with Convention => C;
 
+	generic
+		type Pixel  is private;
+		type Raster is array (Integer range <>, Integer range <>) of aliased Pixel;
+		Default : Pixel;
+	package Raster_Conversions is
+		procedure Copy (
+			Source : in     Raster;
+			Target : in out Surface)
+		with
+			Pre => Source'Length (1) = Target.h
+			and Source'Length (2) = Target.w
+			and Target.format.Bits_Per_Pixel = Pixel'Size;
+		-- Copy video raster to sdl surface. Source and target should have same dimensions
+	end Raster_Conversions;
+
 end Video.Backends.SDL.Surfaces;