OpenGl and SDL problem

[Saxcore]

Hi. I've had a look around, and can't seem to find this problem; although it's a very straight forward one. Also I hope this is the right forum!

I'm currently trying out SDL and OpenGL, and have written a simple C++ program to test them out. It compiles fine, and even runs fine when I replace SDL_OPENGL in the SDL_SetVideoMode(.. line with 0.

With the line in, however, it's failing. Would anyone know of any reasons why this might happen?



// Let's see if we can get OpenGL working!
// Compile with:
// g++ test01.cpp `sdl-config --cflags --libs` -lGL -Wall -o TEST01

#include "SDL.h"
#include "SDL_opengl.h"
#include <iostream>

int main()
{
// Set window size
int WIDTH = 1024;
int HEIGHT = 768;

// Set up SDL / Window
SDL_Init(SDL_INIT_EVERYTHING);
SDL_Surface *base = NULL;
if( (base = SDL_SetVideoMode(WIDTH, HEIGHT, 32, SDL_OPENGL)) == NULL)
{
std::cout << "Error loading base window!\n";
return 0;
}

// Set up OpenGL
glClearColor(0,0,0,0);
// ...projection
glMatrixMode( GL_PROJECTION );
glLoadIdentity();
glOrtho( 0, WIDTH, HEIGHT, 0, -1, 1 );

glMatrixMode( GL_MODELVIEW );
glLoadIdentity();

// Draw a square
glBegin(GL_QUADS);
//set colour
glColor4f(1,1,1,1);
//draw sqaure
glVertex3f(25,25,0);
glVertex3f(75,25,0);
glVertex3f(75,75,0);
glVertex3f(25,75,0);
glEnd();

SDL_Delay(2000);

// Clean up SDL
SDL_Quit();

return EXIT_SUCCESS;
}

Cheers, Sam.

[Saxcore]

Ah. After a bit of research, I wasn't aware that certain OpenGL variables needed to be set with the SDL_GL_SetAttribute() function.

..while I still haven't got it working, I think all I'll need to do now is find out which variables I have to set. I'll report back once I've got it going!