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BLT Times

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Well i have this problem in DirectDraw... I have a big surface (1024x768) in videomemory (vm) i also have small surfaces (128x64) in vm when i blt (lpDDS->Blt) the small to the large one and i get 50ms when i put all the surfaces in system-memory and use my ASMBLT (per byte check for color key) function i get 30ms Why this is happening? I know that SYS->VID and VID->SYS is slow but i also know VID->VID is fast but i didn''t know that SYS->SYS is the best! I have TNT AGP Video Card and 350Mhz CPU with 100Mhz DIMMs Can anyone help me with this. Tankns in advance..

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Well, I''m not certain if this is your problem, but here''s my guess...

Sometimes it''s faster to do your operations in system memory when you are using DirectDraw if the hardware doesn''t support what you are doing. The reason for this is that the HEL will have to retrieve data to and from video memory which, as you know, is slow.

Try to verify that there is hardware support for all the flags you are using to be certain that everything is really just happening in video RAM.

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To I-Shaolin

I only use Source Color Keying nothing else.
You mean if this is supported in my HW?
Thanks anyway.

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