NAME¶

SDL_SetSurfaceAlphaMod - Set an additional alpha value used in blit operations.

SYNOPSIS¶

#include <SDL3/SDL_surface.h>

bool SDL_SetSurfaceAlphaMod(SDL_Surface *surface, Uint8 alpha);

DESCRIPTION¶

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)

FUNCTION PARAMETERS¶

surface

the SDL_Surface structure to update.

alpha

the alpha value multiplied into blit operations.

RETURN VALUE¶

for more information.

THREAD SAFETY¶

This function is not thread safe.

AVAILABILITY¶

This function is available since SDL 3.2.0.

SEE ALSO¶

SDL_GetSurfaceAlphaMod(3), SDL_SetSurfaceColorMod(3)