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Revision 10 as of 2011-01-11 23:25:23
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Editor: SheenaSmith
Comment: update content - w/ Sam
Revision 11 as of 2014-01-11 13:52:41
Size: 1336
Comment: Removed spaces in example.
Deletions are marked like this. Additions are marked like this.
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SDL_LockSurface( surface ); SDL_LockSurface(surface);
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SDL_UnlockSurface( surface ); SDL_UnlockSurface(surface);

SDL_LockSurface

Use this function to set up a surface for directly accessing the pixels.

Syntax

int SDL_LockSurface(SDL_Surface* surface)

Function Parameters

surface

the SDL_Surface structure to be locked

Return Value

Returns 0 on success or a negative error code on failure; call SDL_GetError() for more information.

Code Examples

/* Make the pixels pointer valid in the surface */

SDL_LockSurface(surface);

/* Surface is locked */
/* Direct pixel access on surface here */

SDL_UnlockSurface(surface);

/* Surface is now unlocked */

Remarks

Between calls to SDL_LockSurface() / 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.


CategoryAPI, CategorySurface

None: SDL_LockSurface (last edited 2014-01-11 13:52:41 by PhilippWiesemann)

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