[vtkusers] Need for spherical to cartesian nonlinear transformation.

[Roland Schwarz]

>
> Could this be the reason why Sidney Cadot was seeing a mirrored image
> appear on a textured sphere in this post:?
>
> http://public.kitware.com/pipermail/vtkusers/2002-February/009368.html
>
> If it is, it might be a good idea to change the coordinate system in
> vtkTextureMapToSphere as well.

As far as I can see this could be the reason. But to be honest I did not do
any texture mapping yet.
Perhaps the author of the vtkTextureMapToSphere class wanted to look the
texture from the concave side of the sphere?

I would expect the local system to have the same handing as the system
defined by the partial derivatives of the nonlinear coordinates. (Which is
not true in the case of vtkTextureMapToSphere.)

But I think even if the axes would be changed for this case, this might pose
another question: How do I then manage to look from inside out? Is there no
option to specify an additional transformation to do just that?

Roland

>
> -- Rob
>
> [] Robert Belleman         X  Section Computational Science            []
> [] robbel at science.uva.nl  |X| University of Amsterdam, the Netherlands []
> [] tel: (+31) 20 525 7510  X  http://www.science.uva.nl/~robbel/       []
>