[SDL] Making a screenshot

[Ryan C. Gordon]

> It is as simple as calling:
> 
> SDL_SaveBMP( pSurface,"FILE.BMP" );
> 
> The pSurface is a pointer to a SDL_Surface and the string is the filename to
> save it as.

Yes. And for OpenGL, call glReadPixels() to get the contents of the 
OpenGL framebuffer...then you'd need to get the raw pixel data into some 
format you can use (like a SDL_Surface for SDL_SaveBMP, etc).

--ryan.