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shivanangel
02-16-2006, 11:33 AM
I am trying to create a sphere within a sphere.
The outer sphere has the 'normals' reversed inwards
so that the inner sphere is always visible from any angle.

I constructed this in both 3D Max and Maya, and exported
and checked then in Deep Exploration to make sure that the
normal direction was being retained.
I tried both the supported .obj and .3DS file types.

When I brought the objects into Vizard, the outer sphere
reverted the normals back to the outside.

Does Vizard support this use of normals in this manner?
Is there a line of code I can implement to make
them flip back so I see the inner sphere once again?

~~Thanks
George

farshizzo
02-17-2006, 02:10 PM
Hi,

There are a few ways around this depending on your model. If the model is untextured and symmetrical around the origin, then you can simply apply a negative scale to it:model.scale(-1,-1,-1)If you don't plan on enabling lighting on the model then you can disable back face culling:model.disable(viz.CULL_FACE).If neither of these work then you might want to try the OSG exporter for 3DS max, which exports the model into Vizards native format. You can download it on the Vizard download page.

I'm not very familiar with 3D modelling tools, but if there is an option to reverse the triangle order on the model, then that might work as well. Let me know if none of these options work, and I'll try to figure out another solution.

shivanangel
02-20-2006, 06:26 PM
Just wanted to state for anyone else looking
for an answer to this solution that the only
way I could get the normals flipped was
by using the
3D Studio Max plugin offered here on this
website.

The other methods did not work for me.

But the plugin works marvelously.

~~George Lecakes