On Wed, 17 Jul 2002, Leif Delgass wrote: > On 17 Jul 2002, Michel Dänzer wrote: > > > On Tue, 2002-07-16 at 20:17, Leif Delgass wrote: > > > On Tue, 16 Jul 2002, Keith Whitwell wrote: > > > > > > > > Well, it's not high on my list. I don't think flat-shading is used that > > > > > often, and the changes don't have any effect on smooth shading. Actually, > > > > > it _eliminates_ some saves/restores necessary for unfilled polygons with > > > > > hardware flat-shading. > > > > > > > > > > Actually, I think the problem is larger than mach64. Rage128 has the same > > > > > problem and it appears to have GL compliant flat-shading based on the > > > > > primitive. The problem is that for clipped polygons, the primitive type > > > > > changes, so flat-shading breaks down in that case (like with unfilled > > > > > polygons). I think the templates would have to be changed to copy the > > > > > provoking-vertex color of the polygon being clipped into the vertices of > > > > > the triangles generated by clipping, rather than interpolating the color. > > > > > > > > I'm surprised that this isn't working. Can you verify? I tested on the i810 > > > > at the time & definitely got clipping working there... > > > > > > Here's a couple screenshots with the r128 driver (20020629 build): > > > > > > http://www.retinalburn.net/linux/r128-unclipped-flat.png > > > http://www.retinalburn.net/linux/r128-clipped-flat.png > > > > > > Allen's test program is attached. Maybe someone could check this on > > > Radeon with software tcl as well? > > > > Broken, as expected. As we've both been reporting for some time, > > software clipping is broken in the r128 and radeon drivers. I used to > > suspect a Mesa problem, but the mga driver works. I wish I knew what to > > look for about this problem... > > Actually, since mga uses DO_FLAT in the templates, the provoking-vertex > color gets copied to all vertices. I think the problem is with > interpolation and drivers that define DO_FLAT as zero. Keith said that > i810 worked, but it _doesn't_ set DO_FLAT, which is the define that > controls whether colors are copied. It sets HAVE_HW_FLATSHADE, but that > just causes colors to be saved and restored when working with unfilled > tris.
Oops, I confused myself there. :) If i810 works with DO_FLAT defined as zero, that doesn't support this theory. Maybe there's some other differenece in the way it handles clipped polygons. -- Leif Delgass http://www.retinalburn.net ------------------------------------------------------- This sf.net email is sponsored by:ThinkGeek Welcome to geek heaven. http://thinkgeek.com/sf _______________________________________________ Dri-devel mailing list [EMAIL PROTECTED] https://lists.sourceforge.net/lists/listinfo/dri-devel
