sdempsey@UCSD.EDU (Steve Dempsey) (04/23/91)
In article <1991Apr22.163320.8755@odin.corp.sgi.com>, Kurt Akeley writes: Yes, you really should use v3f on GT, GTX, and VGX machines. The VGX in particular cannot parallelize move/draw syntax commands, and therefore performs very poorly on them. The Personal Iris is unfortunately optimized for the soon-to-be-obsolete move/draw interface. ... v3f calls are the future of the Iris Graphics Library. If you choose to take advantage of the performance advantage of move/draw calls on current Personal Iris equipment, you should consider writing your code to use v3f on all other platforms. -- Kurt Will the performance penalty for using the "high performance" vertex drawing functions on the Personal IRIS go away with IRIX 4.0, or is this embedded in the graphics hardware of the PI? --------------------------------------------------------------------------- Steve Dempsey voice: (619) 534-0208 Dept. of Chemistry Computer Facility, 0314 UUCP: ucsd!sdempsey University of Calif. at San Diego BITNET: sdempsey@ucsd 9500 Gilman Drive INTERNET: sdempsey@ucsd.edu La Jolla, CA 92093-0314 fax: (619) 534-0058
kurt@cashew.asd.sgi.com (Kurt Akeley) (04/24/91)
In article <9104222144.AA26082@chem.chem.ucsd.edu>, sdempsey@UCSD.EDU (Steve Dempsey) writes: |> Will the performance penalty for using the "high performance" vertex drawing |> functions on the Personal IRIS go away with IRIX 4.0, or is this embedded |> in the graphics hardware of the PI? |> --------------------------------------------------------------------------- I know of no plans to retune the Personal Iris family for the 4.0 release. Such tuning would require microcode changes, so the penalty is related to the graphics hardware, if not "embedded" in it. Perhaps someone from the Entry Systems Division will comment? -- Kurt
bennett@sgi.com (Jim Bennett) (04/24/91)
In article <1991Apr23.174445.21278@odin.corp.sgi.com> kurt@cashew.asd.sgi.com (Kurt Akeley) writes: >In article <9104222144.AA26082@chem.chem.ucsd.edu>, sdempsey@UCSD.EDU (Steve Dempsey) writes: > >|> Will the performance penalty for using the "high performance" vertex drawing >|> functions on the Personal IRIS go away with IRIX 4.0, or is this embedded >|> in the graphics hardware of the PI? >|> --------------------------------------------------------------------------- > >I know of no plans to retune the Personal Iris family for the 4.0 release. >Such tuning would require microcode changes, so the penalty is related to >the graphics hardware, if not "embedded" in it. > >Perhaps someone from the Entry Systems Division will comment? > >-- Kurt You're right, I should have commented earlier, but you seemed to be handling this OK. Anyway, I have run many benchmarks on the PI, and the difference between v3f and move-draw lines is not significant. That is, the performance varies more from one run to the next of the SAME benchmark, than it does from a v3f to a move-draw benchmark. So I have always recommended the v calls as the way to go, on all of our machines. If anyone has a benchmark that shows a significant difference between move-draw and v3f, I would like to take a look at it. You can mail it to me at my address below. Jim Bennett (bennett@sgi.com)