OpenGL2D - setup

gistfile1.c

/* first of all, we need to read the dimensions of the 
   display viewport. */
int viewport[4];
glGetIntegerv(GL_VIEWPORT, viewport);

/* setup an orthographic matrix using the viewport 
   dimensions on the projection matrix */
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
glOrtho(0, viewport[2], viewport[3], 0, -1, 1);

/* clear out the modelview matrix */
glMatrixMode(GL_MODELVIEW);
glLoadIdentity();

/* disable depth testing (as we're not using z) */
glDisable(GL_DEPTH_TEST);