[vtkusers] Modifying Medical1.cxx to use images already in memory

[Norman Young]

I changed the threshold value and that did the trick.  Thanks!

Norman

On 10/14/06, Kalpathi R Subramanian <krs at uncc.edu> wrote:
>
> Very likely, no geometry is being generated for this threshold value..
> try values you know for sure
> will generate some polygonal data..
>
>     == krs
>
> Norman Young wrote:
>
> > Hi,
> >
> > I'm new to VTK and have what seems to be a pretty basic question.  I'm
> > trying to modify the Medical1.cxx sample so that instead of reading
> > from disk using vtkVolume16Reader, it uses pixel data that I already
> > have in memory in my application. What might be the best way of doing
> > that?
> >
> > So far, I've created (I think) a volume with vtkImageData, then tried
> > to set the input on the vtkContourFilter to the volume.  It looks
> > something like this (BTW, I'm using C#):
> >
> > vtkImageData volumeData = new vtkImageData();
> >
> > [fill volumeData with some data here]
> >
> > vtkContourFilter skinExtractor = new vtk.vtkContourFilter();
> > skinExtractor.SetInput(volumeData);
> > skinExtractor.SetValue(0, 500);
> > vtkPolyDataNormals skinNormals = new vtk.vtkPolyDataNormals();
> > skinNormals.SetInputConnection(skinExtractor.GetOutputPort());
> >
> > [rest of the sample code here]
> >
> > When I run this, I get this error:
> >
> > ERROR: In ..\..\vtk\Graphics\vtkPolyDataNormals.cxx, line 94
> > vtkPolyDataNormals (060B7520): No data to generate normals for!
> >
> > I assume this is related to not setting the input to the contour
> > filter correctly.  My very vague understanding of the pipeline is that
> > I should be using vtkAlgorithm and input/output ports, but I'm rather
> > confused at how that might work with vtkImageData.
> >
> > Thanks in advance for any help anyone might be able to provide!
> >
> > Norman
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>
>
> --
> K.R.Subramanian                        Phone: (704) 687-8579
> Department of Computer Science         FAX:   (704) 687-3516
> UNC Charlotte, Woodward 435E           Email: krs at uncc.edu
> Charlotte, NC 28223-0001               Web: http://www.cs.uncc.edu/~krs
>
>


-- 
Norman Young
President & Founder
ClearCanvas Inc.
416-340-4800 x5954
norman at clearcanvas.ca