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Speeding up the 16 bit DX Blt

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I have recently discovered that blting a 16 bit bitmap full screen lowers frame rates from the refresh rate to about 11 FPS. Thats horribly slow! (It is only my other 6 year old P166 with 32MB RAM and a cheezy vid card though) Is it just that that computer is just too slow or is there just an over-all speed problem with using 16+bit bitmaps insted of the much more common 256 color surfaces. And if any one could give me some suggestions on how to speed the blt up I''d be a happy little programmer - UraniumRod "When life throughs you horse-raddishes... pass the salad dressing." - Me

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FastBlt() might be able to help on older video cards that have awful hardware blitting support, or no hardware blitting support. One way to find out is to use both FastBlt and Blt calls while timing both of them to see which is faster, if at all.


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that actually depends on how big your primary surface is, and how much vidmem your gfxcard has.
if you create a primary buffer and backbuffer that take up that whole videomemory, your offscreen surface will be placed in systemmemory and without AGP (and i suppose your old card is PCI) the blit will slow down significantly, both BltFast and Blt.
note that when i mean how "big" i mean the combination of bit depth / resolution.
you won''t have much chance to increase your speed, but 11fps sounds a bit slow.
sure you are doin everything properly? if you run windowed mode it could be that windows'' GUI takes up the whole vidmem...

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