Julia Ellery (modellers++at++intersim.co.uk)
Tue, 03 Jun 1997 11:35:41 +0000
I thought you might like to know you are not alone in trying to
overcome this problem! I too received the "usual" comments about
changing the near clipping plane, which of course is not much
help since in many applications you need a reasonably close
near clip AND other things such as fog get affected if you
start changing such values.
Anyway, this may be of some help:
The default mode for pfLayer is "FAST". This results in the flickering
problems you describe. It ALWAYS will! The alternative is to change
the mode for pfLayer to "HIGH QUALITY". I believe this can be
done by a special MultiGen call before the call to pfLoadFile,
or directly in the MultiGen code for their loader, if you are in
the habit of changing this.
This "HIGH_QUALITY" uses stencil planes and this CURES the flickering
problem: Hurrah...... BUT unfortunately we have come across side
affects. I'll describe these affects here in case you come across
them but they might be related to the hardware we are using
(High Impacts) and of course, the endless list of patches...
Side affect: With "HIGH QUALITY" we have occulting problems on and
around the surfaces concerned.
There was debate at one time about this being related to
transparent surfaces only but this is looking unlikely.
So currently, I have the unsatisfactory situation of 2 versions of
the loader and the modellers have the choice of a
flickering problem or occulting problem! Most choose the one that
cures the flicker but racetrack databases use the other!
Hope this is of some help, or at least confirmation that you
are NOT imagining the problem (which sadly seems to be what some
would try to make you believe).
Good luck.
Julia Ellery,
Senior Visual Software Engineer,
Intersim Limited, Units 7-8, Thorgate Road, Littlehampton. Sussex. UK
Tel: +44 (0)1903 733428
Fax: +44 (0)1903 730246
email: modellers++at++intersim.co.uk
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