ra@sun1.ruf.uni-freiburg.de (Christoph Ramshorn) (04/18/91)
We recently upgraded to 3.3.2 on our 4D20G and have a problem with Gouraud shading since: some triangles are rendered in green or magenta hues regardless of their actual color; the edges of those triangle edges are colored correctly, though. Which triangles show those wrong colors depends on light source position (infinitely distant lights used), but the effect does not seem to follow any rule. This bug(?) is also observable the "flip (martini, x29, etc.)" demos. From hinv: 1 12 MHZ IP6 Processor FPU: MIPS R2010A/R3010 VLSI Floating Point Chip Revision: 1.5 CPU: MIPS R2000A/R3000 Processor Chip Revision: 1.6 ... Graphics board: GR1.1 Bit-plane, Z-buffer options installed Any bug fixes, workarounds, suggestions available? We'd really appreciate... Christoph Ramshorn, Geologisches Institut, Albertstr.23-B D-7800 Freiburg i.Br., West Germany ra@trias.geologie.uni-freiburg.de Phone +49 761 203 2408 Fax +49 761 203 2463
kalle@sima.sintef.no (Karl Henrik Eggestad) (04/18/91)
I have a similar problem with a code that works very well on my 4D25TG but really sc**ws up on my 4D320VGX. That as well is with Gouraud-shaded polys (triangs and quads) that have a nice soft shade on the 4D25 but are multi- colored facets on the VGX. The code was recompiled from the 25 to the 320... Vitals are . IRIX 3.3.1 on both . infinite lighting model . pretty simple shading model . no textures . model size ... less than 3,000 polygons Any hints ? I hate to tell all my users that... oh well.. you better stick to the Personal Iris.. the VGX isn't feeling too well these days..." Mail or post (if info is of public interest) Karl Eggestadm research scientist SINTEF Industrial math, Norway ========================================================================================== Opinions are mine, but my employer would mean the same things if he knew is' Opinions are mine, but my employer would mean the same things if he knew his own good... ====================================================================================
bennett@sgi.com (Jim Bennett) (04/19/91)
In article <1991Apr17.205152.21270@sun1.ruf.uni-freiburg.de> ra@sun1.ruf.uni-freiburg.de (Christoph Ramshorn) writes: > > > We recently upgraded to 3.3.2 on our 4D20G and have a problem with >Gouraud shading since: some triangles are rendered in green or magenta hues >regardless of their actual color; the edges of those triangle edges are colored >correctly, though. Which triangles show those wrong colors depends on light >source position (infinitely distant lights used), but the effect does not seem >to follow any rule. This bug(?) is also observable the "flip (martini, x29, >etc.)" demos. I tried running flip on a similar configuration (my machine was a GR1.2, a later rev of the graphics board), and I didn't see any problem. I haven't received any bug reports like this from the field. Is any one else out there experiencing a problem like this? >Christoph Ramshorn, Geologisches Institut, Albertstr.23-B >D-7800 Freiburg i.Br., West Germany >ra@trias.geologie.uni-freiburg.de >Phone +49 761 203 2408 Fax +49 761 203 2463 Jim Bennett (bennett@sgi.com)