Hi I a absolutely a newb in c++, opengl, and sdl, my goal is to make animations, music videos and even one day games, I have started out with sdl and opegl to make a window and change the colours, origionally I had a program to make a window but I altered it to change the colours and it initially crashed, I fixed that in the nested loops in main but then I noticed clicking the x at the top left of the window doesn’t make the program quit anymore!
Please help me fix this I just feel my skills are absolutely awful, thanks!
#include <SDL2/SDL.h>
#include <SDL2/SDL_opengl.h>
#include <GL/glu.h>
#include <GL/glut.h>
#include <stdio.h>
#include <string>
// -lSDL2 -lGLU -lglut -lGL
//Screen dimension constants
const int SCREEN_WIDTH = 640;
const int SCREEN_HEIGHT = 480;
//Starts up SDL and creates window
bool init();
//Frees media and shuts down SDL
void close();
//The window we'll be rendering to
SDL_Window* gWindow = NULL;
//The open gl square
float glSquareblk();
float glSquarerd();
float glSquaregrn();
float glSquarebl();
//Opengl context
SDL_GLContext gContext;
bool init()
{
//Initialization flag
bool success = true;
//Initialize SDL
if( SDL_Init( SDL_INIT_VIDEO ) < 0 )
{
printf( "SDL could not initialize! SDL_Error: %s\n", SDL_GetError() );
success = false;
}
else
{
//Create window
gWindow = SDL_CreateWindow( "SDL Tutorial", SDL_WINDOWPOS_UNDEFINED, SDL_WINDOWPOS_UNDEFINED, SCREEN_WIDTH, SCREEN_HEIGHT, SDL_WINDOW_OPENGL | SDL_WINDOW_SHOWN );
if( gWindow == NULL )
{
printf( "Window could not be created! SDL_Error: %s\n", SDL_GetError() );
success = false;
}
else
{
}
}
return success;
}
void close()
{
//Destroy window
SDL_DestroyWindow( gWindow );
gWindow = NULL;
//Quit SDL subsystems
SDL_Quit();
}
float glSquareblk()
{
glClearColor(0.0,0.0,0.0,1.0);
glClear(GL_COLOR_BUFFER_BIT);
glColor3f(1.0,1.0,1.0);
glOrtho(-1.0,1.0,-1.0,1.0,-1.0,1.0);
glBegin(GL_QUADS);
glVertex2f(-0.5,-0.5);
glVertex2f(-0.5,0.5);
glVertex2f(0.5,0.5);
glVertex2f(0.5,-0.5);
glEnd();
glFlush();
}
float glSquarerd()
{
glClearColor(1.0,0.0,0.0,1.0);
glClear(GL_COLOR_BUFFER_BIT);
glColor3f(1.0,1.0,1.0);
glOrtho(-1.0,1.0,-1.0,1.0,-1.0,1.0);
glBegin(GL_QUADS);
glVertex2f(-0.5,-0.5);
glVertex2f(-0.5,0.5);
glVertex2f(0.5,0.5);
glVertex2f(0.5,-0.5);
glEnd();
glFlush();
}
float glSquaregrn()
{
glClearColor(0.0,1.0,0.0,1.0);
glClear(GL_COLOR_BUFFER_BIT);
glColor3f(1.0,1.0,1.0);
glOrtho(-1.0,1.0,-1.0,1.0,-1.0,1.0);
glBegin(GL_QUADS);
glVertex2f(-0.5,-0.5);
glVertex2f(-0.5,0.5);
glVertex2f(0.5,0.5);
glVertex2f(0.5,-0.5);
glEnd();
glFlush();
}
float glSquarebl()
{
glClearColor(0.0,0.0,1.0,1.0);
glClear(GL_COLOR_BUFFER_BIT);
glColor3f(1.0,1.0,1.0);
glOrtho(-1.0,1.0,-1.0,1.0,-1.0,1.0);
glBegin(GL_QUADS);
glVertex2f(-0.5,-0.5);
glVertex2f(-0.5,0.5);
glVertex2f(0.5,0.5);
glVertex2f(0.5,-0.5);
glEnd();
glFlush();
}
int main( int argc, char* args[] )
{
//Start up SDL and create window
if( !init() )
{
printf( "Failed to initialize!\n" );
}
else
{
//Main loop flag
bool quit = false;
gContext = SDL_GL_CreateContext( gWindow );
//Event handler
SDL_Event e;
//While application is running
while( !quit )
{
//Handle events on queue
while( SDL_PollEvent( &e ) != 0 )
{
glSquareblk();
SDL_Delay(3000);
SDL_GL_SwapWindow( gWindow );
glSquarerd();
SDL_Delay(3000);
SDL_GL_SwapWindow( gWindow );
glSquaregrn();
SDL_Delay(3000);
SDL_GL_SwapWindow( gWindow );
glSquarebl();
SDL_Delay(3000);
SDL_GL_SwapWindow( gWindow );
//User requests quit
if( e.type == SDL_QUIT )
{
quit = true;
//Free resources and close SDL
close();
return 0;
}
}
}
}
}