VRML models and OpenGL Light

I ve loaded VRML models into my OpenGL scene but the light has no effect on them. Is it possible to apply OpenGL lights to VRML models?

thx for every hint!

Do VRML models hold any normal data? I don’t recall seeing any last time I was playing with one.

Your problem is probably the normals. Calculate face normals properly, and your lighting should work fine.

Actually I did the VRML models with 3d Studio max 5.0. and as far as I know the VRML exporter calculates normals. But in case it doesn’t how can I calculate normals in OpenGL for an imported VRML model?

Hi !

As almost always, use google…

Have a look at: http://www.geocities.com/Paris/LeftBank/1160/normals.htm

Just to pick my first hit, it shows how to calculate the normals when you import the geometry (surface normals), if you want vertex normals it is a little more messy, but I would suggest you have a look at the source code for the Graphics Gems book’s they contain code to do vertex normal calculations on meshes.


[This message has been edited by mikael_aronsson (edited 10-27-2003).]