[vtkusers] mixing vtkImageActor with solidly rendered vtkPolyData

[Mathieu Coursolle]

I don't know why you only see your wireframe actors.
Are you using a vtkImageViewer2?

The following is taken from vtkImageViewer2 documentation:
<http://www.vtk.org/doc/nightly/html/classvtkImageViewer2.html>

"This can be used to annotate an image with a PolyData of "edges" or or
highlight sections of an image or display a 3D isosurface with a slice
from the volume, etc. Any portions of your geometry that are in front of
the displayed slice will be visible; any portions of your geometry that
are behind the displayed slice will be obscured."

Does PolyData of "edges" mean that filled polydata won't be displayed
properly?

Mathieu

>Hi Mathieu,
>
>thanks for your quick reply!  
>Yes, the polydata are all on the same layer as the image.
>I would like to know why the contour lines show since they are
>also in the same plane as the image (and the polygon) 
>but the polygon will not?  The polygon actor is only
>visible when rendered in wireframe mode.
>
>Dean
>
>> Subject: Re: [vtkusers] mixing vtkImageActor with solidly rendered
>>  vtkPolyData
>> 
>> Hi,
>> 
>> Is the polydata on the same layer as the image? I mean,
>> if the image origin is (originX, originY, originZ), the
>> polydata origin should be closer to the camera in the
>> direction of projection to make sure it is always visible.
>> Otherwise it may appear or not if they are defined at the same
>> position.
>> 
>> I usually define an epsilon value to the polydata to put in
>> front of an image. If my image is at (originX, originZ, 0), I put my
>polydata
>> position as (posX, posY, epsilon).
>> 
>> Hope it will help...
>> 
>> Thanx.
>> 
>> MAthieu
>> 
>> --
>> > >
>> >in a renderer I have a vtkImageActor (ivar of vtkImageViewer2)
>> >showing a slice of a 3D image.  On top of that are
>> >two vtkActors rendering 2D contours (vtkPolyData lines) from a
>> >segmentation and
>> >another actor rendering a 2D filled segmentation region (
>> >vtkPolyData solid polygon).  When I scroll through the slices,
>> >each slice's contour lines and polygonal region are
>> >updated.  I can see the lines but the polygons appear
>> >briefly and then disappear.  If I hide the vtkImageActor,
>> >the polygons are clearly there.  If I set the polygon actor
>> >to render as a wireframe, the region is correctly shown as a triangulated
>> >polygon whether or not the image actor is visible or not.
>> >If I toggle between wireframe and solid when the image actor
>> >is visible, the solid polygon will not display: only the wireframe
>> >representation will.  SetCoincidentTopologyToPolygonOffset has no
>> >effect.  How can I mix vtkImageActor with solidly rendered vtkPolyData?
>> >
>> >Dean
>> >
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>> 
>> 
>> 
>> 
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