On Thu, Mar 07, 2002 at 09:38:30PM -0800, Gareth Hughes wrote: > Leif Delgass wrote: > > In looking at the docs, I realized that the mach64 seems not to support > > mipmapping on the secondary texture, as there is only one register for a > > secondary texture offset, as opposed to the 11 for the primary texture. It > > seems as the though the second "texture unit" isn't really a fully fledged > > texture pipeline as it is in other cards (Rage 128 has 2 separate tex_cntl > > regs and a full set of offsets for the second texture unit). > > > > And lending credence to the assertion that mipmapping is broken in > > hardware on mach64, I compiled the mipmap Mesa demo in Windows and the ATI > > driver doesn't support mipmapping either, you just get a yellow triangle. > > Mipmapping on the Rage Pro is busted, period. > > -- Gareth
I had an idea during the last IRC meeting that I wanted to bounce off you wrt mipmapping on the Rage Pro, but you weren't there. After the meeting I forgot about it. In any case, what do you think about per-polygon mipmapping? All hardware that does mipmapping does it per-pixel, but all of the old software engines (i.e., the original Quake) did it per-polygon. Now, I realize that the would be a major hack, but would it be worthwhile in your opinion? If this were done in the driver, what would be the conformance implications? Clearly this would not be strictly conformant behavior. It would most closely resemble GL_*_MIPMAP_NEAREST, but not quite exactly. Would this be another mach64 case where some sort of environment variable would be needed to enable / disable the non-conformant behavior? Part of the reason that I even suggest this as viable for mach64 is performance. If per-polygon mipmapping is done, then the driver might be able to get away with uploading smaller textures to card memory. On laptops with only 4MB of video memory, this could be a win. The fact that it would make things look better is just an added bonus. -- Tell that to the Marines! _______________________________________________ Dri-devel mailing list [EMAIL PROTECTED] https://lists.sourceforge.net/lists/listinfo/dri-devel
