Suggestions for "texture mapping" sprites

First off Sam, great work on the SDL and other libs you have written. They
are first class.

Second, I’m using SDL under windows with the intention that after I’ve
finished with what I’m working it can be moved to other OS’es pretty
painlessly.

The game that I’m trying to build has a large (ie, 1600+x1200+) 2D map with
a number of sprites (32x32 to 256x256) drawn on top of it. There is nothing
3D about the game but I would really like to take advantage of 3D hardware
if present for drawing the sprites as they are rotated with vertex lighting
and alpha blended.

My current plan is to use SDL to do a hardware blit of the map, then write a
software texture mapper to draw the sprites. But after I add bilinear
filtering, vertex lighting and alpha blending it could get kinda slow on a
large number of textures.

What I would like is to use SDL’s blitter to draw the map because it can do
this very very fast and then use the 3D hardware to texture map a bunch of
2D textures on top of the map. Even if I have to special case the code
under windows and write to D3D I’d do it, I just want to know if there is a
better way and/or is it possible to code directly D3D while using SDL.

Drawing the map at a screen res of 1280x1024x16 I’m maxing out at my refresh
rate of 85hz on a p450 with a TNT.

Thanks for any help/input/suggestions/pointers/tips!