[vtkusers] Re: drawing lines on curve surface

[Sebastien BARRE]

At 24/11/2000 09:14, Tao-Pak Chris Tsui wrote:

>I am not sure if I understand what you mean by
>inverted y-axis..

It's a 2D issue.  Widget coordinates are relative to an origin which is at 
the upper left corner of their parent (roughly). But VTK has several 
coordinate system, and the Picker objects needs 2D viewport coordinates, 
which are relative to an origin which is at the lower left corner.

>but this raised another question for
>me..  the skull object I have appeared to be the
>mirror object of the actual skull.. what's left is on
>the right and vice versa....
>and the skull is upside down on the after I rendered
>it.. is that because of the odering of the CT data I
>have or it's caused by something else?

Yes, that's because of the ordering of the CT data. There are several 
tutorial on this :
http://www.hds.utc.fr/~barre/vtk/links.html#examples
         - Make Your Own Visible Woman
         - Creating Models From Segmented Images

and have a look at the examplesTcl/frog directory in the VTK sources, 
everything is in it (especially the SliceOrder file should help you to 
permute your stack).