SDL_LockSurface

Name

SDL_LockSurface -- Lock a surface for directly access.

Synopsis

#include "SDL.h"

int SDL_LockSurface(SDL_Surface *surface);

Description

SDL_LockSurface sets up a surface for directly accessing the pixels. Between calls to SDL_LockSurface and SDL_UnlockSurface, you can write to and read from surface->pixels, using the pixel format stored in surface->format. Once you are done accessing the surface, you should use SDL_UnlockSurface to release it.

Not all surfaces require locking. If SDL_MUSTLOCK(surface) evaluates to 0, then you can read and write to the surface at any time, and the pixel format of the surface will not change.

No operating system or library calls should be made between lock/unlock pairs, as critical system locks may be held during this time.

Return Value

SDL_LockSurface returns 0, or -1 if the surface couldn't be locked.

See Also

SDL_UnlockSurface