SDL-minimal.cpp

#include <SDL2/SDL.h>
#include <GL/glew.h>
#include <string>
#include "Camera.hpp"

static void update_fps_counter(SDL_Window* window, const std::string& title) {
	static std::string text_bar;
	static Uint32 fps_lasttime = SDL_GetTicks(); 
	static Uint32 fps_current; 
	static Uint32 fps_frames;
	static const Uint32 FPS_INTERVAL = 1;
	fps_frames++;
	if (fps_lasttime < SDL_GetTicks() - FPS_INTERVAL * 1000)
	{
		text_bar = title + " | FPS: " + std::to_string(fps_frames) + " | " + std::to_string(1000.0f / fps_frames) + " ms/frame";
		SDL_SetWindowTitle(window, text_bar.c_str());
		fps_lasttime = SDL_GetTicks();
		fps_current = fps_frames;
		fps_frames = 0;
	}
}

int main(int argc, char* argv[])
{
	SDL_Init(SDL_INIT_EVERYTHING);
	//atexit(SDL_Quit);

	SDL_GL_SetAttribute(SDL_GL_RED_SIZE, 8);
	SDL_GL_SetAttribute(SDL_GL_GREEN_SIZE, 8);
	SDL_GL_SetAttribute(SDL_GL_BLUE_SIZE, 8);
	SDL_GL_SetAttribute(SDL_GL_ALPHA_SIZE, 8);

	SDL_GL_SetAttribute(SDL_GL_BUFFER_SIZE, 32);

	SDL_GL_SetAttribute(SDL_GL_DEPTH_SIZE, 16);
	SDL_GL_SetAttribute(SDL_GL_DOUBLEBUFFER, 1);

	//	SDL_GL_SetAttribute(SDL_GL_MULTISAMPLEBUFFERS, 1);
	//	SDL_GL_SetAttribute(SDL_GL_MULTISAMPLESAMPLES, 4);
	SDL_GL_SetAttribute(SDL_GL_ACCELERATED_VISUAL, 1);
	SDL_GL_SetAttribute(SDL_GL_CONTEXT_PROFILE_MASK, SDL_GL_CONTEXT_PROFILE_CORE);
	SDL_GL_SetAttribute(SDL_GL_CONTEXT_MAJOR_VERSION, 4);
	SDL_GL_SetAttribute(SDL_GL_CONTEXT_MINOR_VERSION, 4);

	std::string  title = "SDL";
	int width = 800; 
	int height = 600;
	bool full_screen = false;
	SDL_Window* window = SDL_CreateWindow(title.c_str(), SDL_WINDOWPOS_CENTERED, SDL_WINDOWPOS_CENTERED, width, height, SDL_WINDOW_OPENGL);
	SDL_GLContext glContext = SDL_GL_CreateContext(window);

	//SDL_SetHint(SDL_HINT_RENDER_VSYNC, "1");
	//SDL_GL_SetSwapInterval(1);

	Camera camera;

	GLenum res = glewInit();
	if (glewInit() != GLEW_OK)
	{
		fprintf(stderr, "Error: '%s'\n", glewGetErrorString(res));
	}

	// -- opengl --
	glViewport(0, 0, width, height);
	glClearColor(0.0f, 0.5f, 1.0f, 0.0f);
	int mouseX=0;
	int mouseY=0;
	bool running = true;
	Uint32 lastTime = SDL_GetTicks();
	float total_time = 0.0f;
	while (running)
	{
		SDL_Event event;
		while (SDL_PollEvent(&event))
		{
			if (event.type == SDL_QUIT)
			{
				running = false;
			}

			if (event.type == SDL_MOUSEMOTION)
			{
				//SDL_GetMouseState(&mouseX, &mouseY);
				//mouseX = event.motion.x;
				//mouseY = event.motion.y;
				//printf("mouseX: %i , mouseY: %i\n", mouseX, mouseY);
				//printf("> mouseX: %i , mouseY: %i\n", event.motion.x, event.motion.y);
			}

			if (event.type == SDL_KEYDOWN)
			{
				//int value = event.key.keysym.scancode;
				switch (event.key.keysym.sym)
				{
				case SDLK_ESCAPE:
					running = false;
					break;
				}
			}
			if (event.type == SDL_KEYUP)
			{
				//int value = event.key.keysym.scancode;
				switch (event.key.keysym.sym)
				{
				case SDLK_ESCAPE:
					running = false;
					break;
				case SDLK_SPACE:
					full_screen = !full_screen;
					SDL_SetWindowFullscreen(window, full_screen ? SDL_WINDOW_FULLSCREEN : NULL);
					break;
				}
			}
			if (event.type == SDL_MOUSEBUTTONDOWN)
			{
				int value = event.button.button;
			}
			if (event.type == SDL_MOUSEBUTTONUP)
			{
				int value = event.button.button;
			}
		}
		// -- update --
		//SDL_PumpEvents();
		Uint32 time = SDL_GetTicks();
		float deltaTime = ((float)(time - lastTime)) / 1000;
		total_time += deltaTime;
		lastTime = time;
		camera.move(deltaTime);

		update_fps_counter(window, title);

		// -- render --
		glClear(GL_COLOR_BUFFER_BIT);

		SDL_GL_SwapWindow(window);
	}

	SDL_GL_DeleteContext(glContext);
	SDL_DestroyWindow(window);
	SDL_Quit();

	return 0;
}