#include "SDL.h"
SDL_Surface *SDL_ConvertSurface
(SDL_Surface *src, SDL_PixelFormat *fmt, Uint32 flags);
Creates a new surface of the specified format, and then copies and maps the given surface to it. If this function fails, it returns NULL.
The flags parameter is passed to SDL_CreateRGBSurface and has those semantics.
This function is used internally by SDL_DisplayFormat.