gl-test.c

/* compile with `gcc ramdisk/opengl.c -lSDL2 -lGL` */

#include <SDL2/SDL.h>
#include <GL/gl.h>
#include <stdio.h>

int main(int argc, char* argv[]) {
	SDL_Init(SDL_INIT_VIDEO);
	SDL_Window* win = SDL_CreateWindow("test", SDL_WINDOWPOS_CENTERED, SDL_WINDOWPOS_CENTERED, 512, 512, SDL_WINDOW_OPENGL);
	SDL_GLContext ctx = SDL_GL_CreateContext(win);
	SDL_GL_SetAttribute(SDL_GL_CONTEXT_PROFILE_MASK, SDL_GL_CONTEXT_PROFILE_CORE);
	SDL_GL_SetAttribute(SDL_GL_CONTEXT_MAJOR_VERSION, 3);
	SDL_GL_SetAttribute(SDL_GL_CONTEXT_MINOR_VERSION, 0);
	SDL_GL_SetAttribute(SDL_GL_DOUBLEBUFFER, 1);
	SDL_GL_SetSwapInterval(1);
	int value = 0;
	SDL_GL_GetAttribute(SDL_GL_CONTEXT_MAJOR_VERSION, &value);
	printf("major version: %i\n", value);
	SDL_GL_GetAttribute(SDL_GL_CONTEXT_MINOR_VERSION, &value);
	printf("minor version: %i\n", value);
	glClearColor(0.7, 0.0, 0.7, 1.0);
	glClear(GL_COLOR_BUFFER_BIT);
	SDL_GL_SwapWindow(win);
	SDL_Delay(1000);
	SDL_GL_DeleteContext(ctx);
	SDL_DestroyWindow(win);
	SDL_Quit();
	return 0;
}