[vtkusers] flipping the scene:(Parity Transform)

[Bill Lorensen]

The example in examplesTcl/reverse.tcl show how to use the filters.

Bill

At 07:59 PM 12/13/00 -0500, David Gobbi wrote:
>Hi Bob,
>
>Just to finalize this, my reply to you was half right and Bill's
>was half wrong (or less, it just contained a typo) so here is the
>final story (which you have probably figured out for yourself by now):
>
>vtkTransformPolyData->SetTransform(transform)
>vtkReverseSense
>
>My suggestion of using vtkPolyNormals is incorrect, it will just
>re-generate incorrect normals.
>
>  - David
>
>On Wed, 13 Dec 2000, Bill Lorensen wrote:
>
> > Bob,
> > You can use vtkPolyDataTransform, folllowed by a vtkReverseSense
> > 
> > Bill
> > 
> > At 04:13 PM 12/13/00 -0500, Fletcher, Bob (GEAE) wrote:
> > >I have a scene with many actors. I need to flip the whole scene around,
> > >replacing z with -z. (Parity Transform).
> > >
> > >I tried 
> > >myactor  SetScale 1 1 -1
> > >
> > >The geometry looks ok, but it's all rendered flat black. Without the
> > >Setscale it's colored by it's scalar value.  Is this some kind of normal
> > >vector problem? 
> > >
> > >I can setScale -1 -1 1, and the colors are ok, but of course it doesn't
> > >change my geometry!
> > >
> > >Is there a better approach? This seemed simplest.  Is ther a Left
> > >handed/righthanded corrdinate system flag hiding someplace?
> > >
> > >Any thoughts?
> > >
> > >Bob.