[Plib-devel] [PATCH] crease for ac3d files and speedup

[Mathias <Mat...@gm...>]

Hi all,

During the past days I have done some profiling on flightgear. One final=20
outcome of that work was, that most time is spent in ssg routines (yes, ssg=
=20
not OpenGL!!). The problems are the huge amount of small leaf nodes we get=
=20
from the ac file loader. That vertex optimization pass makes this a bit=20
better but there was still room for improovement.

I have now changed the ac3d file loader to first collect all surface elemen=
ts=20
of a leaf object and then split them to a minimum number of leaf nodes=20
according to material and colour properties.

=46or my local setup (radeon 9100, athlon XP 2400+) this gave me a framerat=
e=20
speedup up to 40% (16 fps -> 26fps, for the c172 rendered in a window to no=
t=20
hit the ancient radeons fill rate limit). I would guess that the average=20
speedup is about 25%-30%.

As a /sideeffect/ it was now easy to implement the crease tag for ac3d file=
s.
Ac3d models look now the same as in ac3d.

Attached is a patch to todays plib anoncvs.

Is sombody there with cvs write access to plib? Can somebody apply this pat=
ch,=20
please?

     Greetings

            Mathias

=2D-=20
Mathias Fr=C3=B6hlich, email: Mat...@gm...