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Hightower
04-03-2008, 07:11 AM
hey boys and girls,
I work on an driving simulator based on OpenGL Performer 3.0. To build the database I use MultiGen Paradigm Creator 3.3.
So that means I create an objekt, with texture in creator (*.flt) and convert it to a Performer file (*.pfb) [I use the performer included converter].
But now the colors of the model are darker (imported in Performer) as in creator?! Why is it so? How can I get the same luminance? In Performer are only 2 lightpoints given, which do not illuminate objekts as for example a global light source I would use!

So is there someone who can answer my question?
best regards
Hightower

havokentity
04-04-2008, 03:12 AM
Check your normals. Renormalize your normals

dorbie
04-05-2008, 08:31 PM
Your normals will be correct after loading so don't worry about that.

You need to match the lighting using Performer. There's a difference between a material description in OpenFlight and the rendered appearance in Performer after lighting. Lighting is fundamental to appearance.

Make sure you add enough light remembering that local lights can attenuate. Also add ambient to the light model or the glLight if you need something a bit more than harsh ligting.

You can also disable lighting and see what the object looks like, I suspect you will find that it looks OK and lighting is your problem.

I'm too rusty on the Performer stuff to give you more information but vertex color can be bound to Material diffuse and Ambient terms using the API. Vertices may or may not hae vertex color and you can use or ignore this attribute glMaterialColor in the OpenGL layer but there are equivalent Performer calls that track state and play nicely with the state information it maintains.