treed@sgidallas.sgi.com (Thomas E Reed) (06/07/89)
USER: Randy Blaschke Bell Helicopter Arlington TX (817) 280-5860 Has asked me to post this request for information. He is having a problem using feedback mode on a 4D80/GT rev 3.1C. He is using feedback mode to select the nearest of a group of overlapping triangular polygons. The problem is closely tied to the viewing matrix being used. Feedback mode will return incorrect z-values at times. However by changing the viewing matrix ala the "ortho" and "polarview" commands the problem will go away. It seems to improve by shifting the object nearer the far clipping plane. We isolated it to the viewing matrix but haven't gone much farther since changing the viewing parameters somewhat fixes the problem. Has anyone had similar troubles? Does anyone have a possible explanation? Any input on feedback mode is welcome. You can call Randy directly or mail me and I will forward it. thanks in advance.... -- Tom Reed SGI - Dallas email: treed@sgidallas@sgi.com vmail: 8705 phone: 214-788-4122
rpaul@dasys1.UUCP (Rod Paul) (06/20/89)
In the manuals is an example that shows loading an identity matrix for a feedback() procedure. It works.