cohen@theory.TC.Cornell.EDU (Ron Cohen) (05/26/91)
We are thinking of buying a 320H for solid modeling, in particular molecular modeling using Phigs. The IBM specs for the 320 with 24bit graphics are 10K Gouraud shaded polygons/sec. Is this fast enough for real time video? Does anyone have experience with such an application on an R6000? Is it possible to save the frames and play them back at video speeds if that raw rate isn't fast enough? Any experiencce making video directly from an R6000? Any advice would be appreciated. We are also considering an HP 720 PRX, which rates at 21K polygons /sec, but is 16 bit (8+8) rather than 24. We appreciate the help. Ron Cohen Geophysical Laboratory Carnegie Institution of Washington Washington, D.C.
brownr@addiction.rtp.dg.com (Randy Brown) (05/29/91)
In article <1991May26@batcomputer.tn.cornell.edu> cohen@quartz.ciw.edu writes: > >We are thinking of buying a 320H for solid modeling, in particular >molecular modeling using Phigs. The IBM specs for the 320 with >24bit graphics are 10K Gouraud shaded polygons/sec. Is this fast >enough for real time video? Does anyone have experience with such >an application on an R6000? Is it possible to save the frames >and play them back at video speeds if that raw rate isn't fast enough? Real-time at 30 frames/second gives you 300 polys/frame at best with a 10K rated system. Molecular modeling of any reasonable scale would have many molecules, main chains, and assorted parts. The UNC-CH graphics group has been successfully performing molecular modeling tasks with a 30K poly/sec machine, but does not use polys for spheres, which your machine probably would. How many polys per sphere will you use? 256, 128, 64? You start to run out of polygons pretty quickly at that rate. So, I would expect that you will need to save frames, and perform single-frame recording onto a VTR, unless you have a frame store like an Abekas to dump them to tape with (which is a large investment for starting out). > Ron Cohen > Geophysical Laboratory > Carnegie Institution of Washington > Washington, D.C. Good luck with it! Randy no new .sig yet