however, no cards have support for advanced blitting functions such as alpha blending, add-blending, etc etc, which is why we're all making our own.

-- Remnant

Stuff to remember:
-Some AGP cards can hardware blit to and from system and video memmory very very fast, some actually use system ram as video ram (watch your system ram drop by up to 16Megs). Example Intel's I740 very nice graphics card.
-Some PCI cards support DMA blitting to and from system ram but to take advantage of hardware acceleration lock the surface, some cards can get around this.
-As far as I know no ISA card supports hardware blitting with system ram.

Soluttion:
Write 3 update/blitting routines
1. Takes advantage of AGP cards that support system to video ram blits.
2. Takes advantage of DMA blitting if the lock call is not required use the 1st routine.
3. Write your own blitting routine in ASM for system to video ram blits as that will be faster then Direct X software blits.

If anyone wants more details on how to check for these features contact me on
phillip.stiby@u.genie.co.uk

Stibbs - Multimedia Expert