1SDL_DisplayFormatAlpha(3) SDL API Reference SDL_DisplayFormatAlpha(3)
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6 SDL_DisplayFormatAlpha - Convert a surface to the display format
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9 #include "SDL.h"
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11 SDL_Surface *SDL_DisplayFormatAlpha(SDL_Surface *surface);
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14 This function takes a surface and copies it to a new surface of the
15 pixel format and colors of the video framebuffer plus an alpha channel,
16 suitable for fast blitting onto the display surface. It calls SDL_Con‐
17 vertSurface
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19 If you want to take advantage of hardware colorkey or alpha blit accel‐
20 eration, you should set the colorkey and alpha value before calling
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23 This function can be used to convert a colourkey to an alpha channel,
24 if the SDL_SRCCOLORKEY flag is set on the surface. The generated sur‐
25 face will then be transparent (alpha=0) where the pixels match the
26 colourkey, and opaque (alpha=255) elsewhere.
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29 If the conversion fails or runs out of memory, it returns NULL
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32 SDL_ConvertSurface, SDL_SetAlpha, SDL_SetColorKey, SDL_DisplayFormat,
33 SDL_Surface
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37SDL Tue 11 Sep 2001, 23:01 SDL_DisplayFormatAlpha(3)