[vtkusers] Wrong coordinate system for bounds computation in vtkClipPlanesPainter

[xabivtk]

Hi, 

For the 5.10 release, the method vtkClipPlanesPainter::UpdateBounds has been
implemented to fix a bug, but i think that there is a transformation missing
for the planes, leading to the incorrect culling of some props in the case
they have a transformation matrix different than identity. 

this->ClippingPlanes are expressed in world coordinates, after the use of
the actor's matrix, whereas the bounds are in data coordinates 

To clip the data, the planes are used in
vtkOpenGLClipPlanesPainter::RenderInternal to be passed to glClipPlane after
beeing transformed from world to data coords with the use of the actor's
matrix. 
But in the rendering pipeline we have a call to
vtkClipPlanesPainter::UpdateBounds where these planes are considered to be
in the data coordinates.

Here is the calling stack: 

vtkClipPlanesPainter::UpdateBounds              ===> original data bounds,
but actor's world coordinates transformed planes 
vtkPainterPolyDataMapper::ComputeBounds 
vtkPolyDataMapper::GetBounds 
vtkActor::GetBounds                                  ===> actor's
transformation Matrix applied to the bounds 
vtkFrustumCoverageCuller::Cull                    ===> Prop can be
incorrectly culled !!!! 

So in the method vtkClipPlanesPainter::UpdateBounds, the planes should be
transformed with the actor's matrix before changing the bounds. 


I used to fill a report in the Mantis Bug Tracker for this kind of bug, but
it seems that vtk has been removed from it... 



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