some questions on s-geometry

[paul@PERSEPHONE.aegean-sea.dialnet.symbolics.com (Paul Cross)]

    Date: Sat, 06 Oct 90 23:34:27 +0100
    From: ks@dfki.uni-sb.de (Kurt Schreiner)


    We noticed some "anomaly" in our version of S-Geometry (*): There are
    some "hidden" lines visible!!!!

    Is this:
    - a known "anomaly"???
    - version dependent?
    - fixed in a currend/future release?

If I remember correctly S-Geometry uses the painters algorithm to draw
lines.  The trade off is between accuracy and speed, and S-Geometry
chose this algorithm for speed.  So, this is a known"anomaly," not as
far as I know version-dependent, and not fixed in current nor future
releases.

Gratuitous subdivision will help if you have a pesky line that you want
hidden.  You might also try using the clipping planes to remove the
line.  I once did six minutes of wire frame animation using the
technique of adding extra lines to hide other lines to make things look
right.  Without the extra lines the "hidden" lines were popping on and
off depending on the position of the camera.  If this isn't enough
information I can help you with this offline, since much of slug
probably isn't interested.

Someone else will have to help you with the version numbers.  I beleive
it's 14.101 for 7.2.

    What are the currend released versions of the S-Products:
    - for Genera 7.2 on 36xx?
    - for Genera 7.4i on MacIvory?
    - for Genera 8.0.x:
       - on MacIvory?
       - on 36xx?

    Will the S-Products be supported on the UX{4,12}00S?
    If no, why not? (Not feasible on X?)