SDL_SetSurfaceAlphaMod

Set an additional alpha value used in blit operations.

Header File

bool SDL_SetSurfaceAlphaMod(SDL_Surface *surface, Uint8 alpha);

SDL_Surface *	surface	the SDL_Surface structure to update.
Uint8	alpha	the alpha value multiplied into blit operations.

(bool) Returns true on success or false on failure; call SDL_GetError() for more information.

When this surface is blitted, during the blit operation the source alpha value is modulated by this alpha value according to the following formula:

srcA = srcA * (alpha / 255)

This function is not thread safe.

This function is available since SDL 3.2.0.