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Mafian

DDBLTFX Alpha Blending

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Taking a look at the DDBLTFX structure, there seems to be Alpha Blending capabilities with the Blt function. I would really like to use translucency graphics in my games, but I cant find anyplace that describes how to use the Alpha-related members in the DDBLTFX structure. Does anyone know how to use this structure to set up a simple translucent blt in Direct Draw?

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Well, I searched all the DX7 SDK and I didn''t find a reference to use alpha blending in Blt(); function... So I''m doing my own Alpha Blending function using MMX and ASM. I saw a ddscaps capability which would create a surface as an aplha map, but I really don''t know how to use it, or what this means. But I asked mysleft if, in 32-bit color mode, as it being ARGB, if we set the A byte, it could give us any alpha taste... Dunno.

If someone knows anything, please post here.

bye!

-LordAsm-

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most hardware vendors dont support alphablending in directdraw. they feel you should be making 3d games instead since thats what ppl are buying and what the industry is doing. personally ithink its silly. unfortunatly you either need to use d3d/ogl for accelerated alphablending or write your own alpha functions (see article on gamedev for software blending help).

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Yeah, I''ve written my own alpha blending routine in C++. My god, it''s stinking slow! Guess I just have to learn ASM...

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