Re: [Plib-devel] Double-sided material fix to 3DS loader for

[Curtis L. O. <cu...@me...>]

> Per Liedman writes:
> > By the way, I use a modified version of the tux_example to test the
> > 3ds-loader, and have stumbled across something I think is sort of
> > odd. If I load one of the models supplied by Wolfram Kuss (550.3ds),
> > it looks what I think it should look like (a large building), but if
> > I also load the pedestal model from the original tux_example, the
> > whole building turns white (no lighting or anything)!  Any
> > suggestions to what might cause this? (The loader does not use
> > GL_COLOR_MATERIAL, if that is of any interest.)

Curtis L. Olson writes:
> I've noticed similar behavior with ssg ... I've never been able to get
> an ssgSimpleState to work consistantly if it doesn't use
> gl_color_material and if it doesn't have a texture.  I've seen this
> enough times to speculate that either:
> 
> a) there is some state changing bug in ssg
> 
> b) there is some non-obvious thing that needs to get done to make this
> work right

Just in case what I wrote was confusing.  If I'm trying to create a
simplestate that sets material properties without enabling
gl_color_material and at the same time doesn't have a texture applied,
then I see really inconsistant results ... it will work at times and
not work at times depending on view direction and position.  Work
being defined as I get what I think I should get, and not-work being
defined as I get an all white shaded surface.  My guess is that as
various objects are culled or drawn, this has a side effect on the
objects in question so that sometimes they are rendered correctly, and
sometimes not.

Curt.
-- 
Curtis Olson   University of MN, ME Dept.       Flight Gear Project
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