[vtkusers] Re: Strange Artefacts with Surface Rendering

[Goodwin Lawlor]

Tobias Mönch wrote:
> Hi vtk'ers!
> 
> I've again some problems. I'm doing a simple SurfaceRendering of a brain using a
> vtkPolyDataMapper (and some smoothing before). When I use no transparency then
> everything is fine.
> But if I set the opacity of the surface-actor to some value below 1.0 the
> following happens:
> The surface seems to turn its inside out when I rotate it in some direction
> (sometimes it looks like this). It also seems that some parts of the surface
> disappear when rotating (as it was clipped). It's no problem to rotate the
> brain-surface back and then everything is completely closed as it should. But in
> some special positions the described things happen.
> 
> Does anyone had the same problems or an idea what the problem could be?
> 
> I attached a screenshot where i marked where the surface already disappeared.
> 

Hi Tobias,

Do you get the same artefacts with BackfaceCullingOn and rendering 
triangles only (using vtkTriangleFilter)?

Goodwin