Gpu940 is a soft 3D renderer that can do many rendering types, including true perspective texture mapping/lighting. The software is designed to operate as a separate process. It's mainly targeted at GPH's GP2X (http://www.gp2x.com) but can be used on other platforms as well.
Commands are sent to the "GPU" using a cyclic buffer. On PC, this buffer is mmapped and shared by the "GPU" and the client.
The GPU performs clipping, projection and drawing. Geometry can be drawn onto as many video buffers as you need (not limited to 2). Textures and Z-buffers are like video buffers, so that any texture or z-buffer can be drawed onto, and that any previous video buffer can serve as a texture or z-buffer.
These details are provided for information only. No information here is legal advice and should not be used as such.