bwidgets/examples/run.hpp

#ifndef BWIDGETS_EXAMPLES_RUN_HPP_
#define BWIDGETS_EXAMPLES_RUN_HPP_

#include <concepts>
#include <functional>
#include <iostream>

#include <SDL2/SDL.h>
#include <SDL2/SDL_ttf.h>

#include <basic_widgets/core/font.hpp>
#include <basic_widgets/core/renderer.hpp>
#include <basic_widgets/w/base/widget.hpp>
#include <basic_widgets/w/horizontal_layout.hpp>
#include <basic_widgets/w/vertical_layout.hpp>

using namespace bwidgets;

template<typename T>
concept Widget = std::derived_from<T, widget::Widget>;

template<Widget W>
void run_example(std::function<void (W*, core::Font*, int, int)> setup, int w=3, int h=3)
{
    try
    {
        core::SDLError::success_or_throw(SDL_Init(SDL_INIT_VIDEO),
                __FILE__, __FUNCTION__, __LINE__);
        core::SDLError::success_or_throw(TTF_Init(),
                __FILE__, __FUNCTION__, __LINE__);

        const core::Size size_init {854, 480};
        auto* font     {new core::Font(core::Font::find("Monospace"), 16)};
        auto* win      {SDL_CreateWindow("basic_widgets example",
                SDL_WINDOWPOS_CENTERED, SDL_WINDOWPOS_CENTERED,
                size_init.w, size_init.h,
                SDL_WINDOW_SHOWN | SDL_WINDOW_RESIZABLE | SDL_WINDOW_UTILITY)};
        auto* renderer {new core::Renderer(win, -1, SDL_RENDERER_ACCELERATED)};
        renderer->blend_mode(SDL_BLENDMODE_BLEND);

        auto* layout   {new widget::HorizontalLayout()};

        for (auto x = 0; x < w; x++)
        {
            auto* col = new widget::VerticalLayout();
            for (auto y = 0; y < h; y++)
            {
                auto* widget = new W();
                setup(widget, font, x, y);
                col->add_widget(widget);
            }
            layout->add_widget(col);
        }

        layout->renderer(renderer);
        layout->viewport({0, 0, size_init.w, size_init.h});

        bool quit {false};
        while (!quit)
        {
            SDL_Event ev;
            while (SDL_PollEvent(&ev) != 0)
            {
                switch (ev.type)
                {
                    case SDL_QUIT:
                        quit = true;
                        break;
                    case SDL_WINDOWEVENT:
                        if (ev.window.event == SDL_WINDOWEVENT_SIZE_CHANGED)
                        {
                            auto size = renderer->output_size();
                            layout->viewport({0, 0, size.w, size.h});
                        }
                        break;
                }
                layout->handle_event(ev);
            }

            renderer->draw_color({50, 60, 70, SDL_ALPHA_OPAQUE});
            renderer->clear();

            layout->render();
            renderer->present();
        }
    }
    catch (const core::SDLError& e)
    {
        std::cerr << "Error: " << e.file << ":" << e.func << ":" << e.line
            << ": " << e.what << std::endl;
    }
}

#endif