###### (This is the documentation for SDL3, which is the current stable version. [SDL2](https://wiki.libsdl.org/SDL2/) was the previous version!) # SDL_PremultiplySurfaceAlpha Premultiply the alpha in a surface. ## Header File Defined in [](https://github.com/libsdl-org/SDL/blob/main/include/SDL3/SDL_surface.h) ## Syntax ```c bool SDL_PremultiplySurfaceAlpha(SDL_Surface *surface, bool linear); ``` ## Function Parameters | | | | | ---------------------------- | ----------- | ----------------------------------------------------------------------------------------------------------------- | | [SDL_Surface](SDL_Surface) * | **surface** | the surface to modify. | | bool | **linear** | true to convert from sRGB to linear space for the alpha multiplication, false to do multiplication in sRGB space. | ## Return Value (bool) Returns true on success or false on failure; call [SDL_GetError](SDL_GetError)() for more information. ## Remarks This is safe to use with src == dst, but not for other overlapping areas. ## Version This function is available since SDL 3.1.3. ---- [CategoryAPI](CategoryAPI), [CategoryAPIFunction](CategoryAPIFunction), [CategorySurface](CategorySurface)