SDL / OpenGL no graphics

[j.bell730]

I'm trying to learn SDL and OpenGL. I'm just starting out creating simple 2d polygons (a triangle, actually). But nothing is showing up in the window. All I get is just a completely black window. I'm writing in C.

Here is my code:

#include "SDL/SDL.h"
#include <GL/gl.h>
#include <GL/glu.h>

int main (int argc, char* args[])
{
SDL_Surface* screen = NULL;

int screenWidth = 1024;
int screenHeight = 768;
int screenBPP = 32;

SDL_Init (SDL_INIT_EVERYTHING);

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

screen = SDL_SetVideoMode (screenWidth, screenHeight, screenBPP, SDL_SWSURFACE);

glClear (GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
glLoadIdentity ();

glTranslatef (0.0f, 0.0f, 0.0f);

glBegin (GL_TRIANGLES);
glColor3f (1.0f, 0.0f, 0.0f);
glVertex3f (0.0f, 1.0f, 0.0f);
glColor3f (0.0f, 1.0f, 0.0f);
glVertex3f (1.0f, -1.0f, 0.0f);
glColor3f (0.0f, 0.0f, 1.0f);
glVertex3f (-1.0f, -1.0f, 0.0f);
glEnd ();

SDL_Flip (screen);

SDL_Delay (3000);

SDL_Quit ();

return 0;
}

I'm compiling with:

gcc sdl.c -lSDL -lGL

What is it that I'm doing wrong?

[Sockerdrickan]

You need to set up your projection matrix, use gluLookAt or something.