You can write directly into your video memory area through assembly. I have done it before, so know it can be done and isn't too painful. You can probably do the same through C++ at worst having to go to asm to do it. You have two buffers you have access to, so it is easy to do double buffering.

As far as the acual spriting goes, you are on your own as far as coming up with the algorithms goes. Chances are good that you won't be able to improve much on whatever algorithms they used to do it, though.

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system specs:
Voodoo 5 5500 agp
tyan 1834d tiger 133 dual 800eb 133mhz FSB
via chipset 133 via apollo pro (don't make this mistake)
256 MB RAM
2 maxtor 60gig ata100 drives
promise ata100 controller
liteon 52 truex cdrom
Linksys ethernet 10/100
Soundblaster Live! (what's so exciting about it??) value edition
300watt power supply (inwin)
about 7 pounds of fans (I'm not kidding)
Suse 7.1(god gnome is crappy compared to CDE)/win2000 based system