v0.1

src/main.cpp

@@ -2,11 +2,95 @@
 #include <iostream>
 
 /* include SDL3 */
-#include "SDL3/SDL.h"
+#include <SDL3/SDL.h>
 /* include GLEW */
-#include "GL/glew.h"
+#include <GL/glew.h>
+
+/* define default window properties */
+#define WINDOW_WIDTH 800
+#define WINDOW_HEIGHT 600
+#define WINDOW_SIZE WINDOW_WIDTH, WINDOW_HEIGHT
+#define APP_NAME "HelloGL"
+
+/* define error codes */
+#define ERROR_STD 1
+#define ERROR_SDL 2
+#define ERROR_OGL 3
 
 int main(int argc, char* argv[]) {
- std::cout << "Hello World!" << std::endl;
+ /* initialize SDL and handle error */
+ if(SDL_Init(SDL_INIT_VIDEO)) {
+ fprintf(stderr, "Failed to initialize SDL!\n%s\n", SDL_GetError());
+ return ERROR_SDL;
+ }
+
+ /* set buffer sizes for the context */
+ 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);
+ /* enable double buffering */
+ SDL_GL_SetAttribute(SDL_GL_DOUBLEBUFFER, SDL_TRUE);
+
+ /* create a window and handle error */
+ SDL_Window* window = SDL_CreateWindow(APP_NAME, WINDOW_SIZE, SDL_WINDOW_OPENGL);
+ if(!window) {
+ fprintf(stderr, "Cannot create a window!\n%s\n", SDL_GetError());
+ return ERROR_SDL;
+ }
+
+ /* create an OpenGL context */
+ SDL_GLContext glContext = SDL_GL_CreateContext(window);
+ /* initialize GLEW and handle error */
+ if(GLenum err = glewInit() != GLEW_OK) {
+ fprintf(stderr, "Failed to initialize GLEW!\n%s\n", glewGetErrorString(err));
+ return ERROR_OGL;
+ }
+
+ /* print OpenGL vendor, renderer and version strings */
+ printf("GL vendor string: %s\n", glGetString(GL_VENDOR));
+ printf("GL renderer string: %s\n", glGetString(GL_RENDERER));
+ printf("GL version string: %s\n", glGetString(GL_VERSION));
+ printf("GLU version string: %s\n", gluGetString(GLU_VERSION));
+
+ /* set the clear color to RGBA(00, 00, 00, FF) */
+ glClearColor(0.0f, 0.0f, 0.0f, 1.0f);
+
+ /* create variables for the main loop */
+ SDL_Event event;
+ bool loop = true;
+ /* enter the main loop */
+ while(loop) {
+ /* clear the buffers */
+ glClear(GL_COLOR_BUFFER_BIT);
+
+ /* render a colored triangle with the old pipeline */
+ glBegin(GL_TRIANGLES);
+ glColor3f(1.0f, 0.0f, 0.0f); glVertex2f(-0.75f, -0.75f);
+ glColor3f(0.0f, 1.0f, 0.0f); glVertex2f(0.75f, -0.75f);
+ glColor3f(0.0f, 0.3f, 1.0f); glVertex2f(0.0f, 0.75f);
+ glEnd();
+
+ /* swap the double buffer */
+ SDL_GL_SwapWindow(window);
+
+ /* enter event loop */
+ while(SDL_PollEvent(&event)) {
+ /* exit the main loop when the 
+ window close button was pressed */
+ if(event.type == SDL_EVENT_QUIT) {
+ loop = false;
+ }
+ }
+ }
+
+ /* delete the context */
+ SDL_GL_DeleteContext(glContext);
+ /* delete the window */
+ SDL_DestroyWindow(window);
+ /* free memory used by SDL */
+ SDL_Quit();
+
  return 0;
 }