NAME

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

HEADER FILE

Defined in SDL3/SDL_surface.h

SYNOPSIS

#include "SDL3/SDL.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

Returns true on success or false on failure; call

SDL_GetError () for more information.

THREAD SAFETY

This function is not thread safe.

AVAILABILITY

This function is available since SDL 3.2.0.

SEE ALSO

•(3), SDL_GetSurfaceAlphaMod(3), •(3), SDL_SetSurfaceColorMod(3)