I'm trying to get a 16-bit color mode that includes a stencil-buff. [update] I was enumerating incorrectly here; skip to next post [/update]. When I enumerate, I find several 16-bit color modes that have a 16-bit z-buffer, which includes 5 bits for the stencil-buff (supposedly). I'm deriving the stencil bit info from DDSURFACEDESC2 object > pixel format > dwStencilBitMask, which is '31' in all these cases. After selecting one of these modes, I call pd3dDev->Clear() and include the D3DCLEAR_STENCIL flag, and I get the "no stencil buffer" error. By the way, if I ignore this error and try to use the stencil buff, of course it doesn't work. I've tried this with a T&L device (geForce2) and the RGB device -- both claim 5 bits, and neither work. Also, note that everything works fine (i.e. my shadow-casting algo) when I have a 32-bit color mode with a 32-bit z-buffer (8 stencil bits). I also check D3DDEVICEDESC7 object > dwStencilCaps, btw. Edited by - Eric on 6/21/00 2:09:00 AM

Ok, I wasn't enumerating correctly before. There is a separate enumeration for z-buffer bit depth, apparently. So here is where I stand now:

- No 16-bit z-buffer w/ any stencil bits on my hardware T&L device (geForce2)
- If I attach a 32-bit z-buffer (w/ 8 stencil bits) to my 16-bit backbuffer, I am unable to SetRenderTarget() my backbuffer. Apparently this is "DDERR_CURRENTLYNOTAVAIL" on my BRAND-NEW , supposedly TOP-OF-THE-LINE geForce2 card. Actually, what matters is that this is (probably) not supported on TNT2s, which are kinda my target card. A 16-bit backbuffer w/ a 32-bit z-buffer is supported in software, btw.

Any suggestions? I just can't believe I have to use 32-bit color, which practically halves my framerate w/ almost no perceptible aesthetic improvement, just so that I can get a stencil-buff.

Edited by - Eric on June 21, 2000 3:15:46 AM