[vtkusers] Volume rendering

[Sepp^ Huber]

Hi all,

I've got the following problem that I'd like to create a volume rendering
for some simple data that I have at my hands. In principle I do have a bunch of
indexed cells/voxels and a corresponding value from radiation measurements.
Now I'd like to create a volume rendering of this data.

In principle I've set everything up including the ray casting functions and
so on. The crucial point is how to provide the data:

 vtkVolumeRayCastMapper* pVolumeMapper = vtkVolumeRayCastMapper::New();
 pVolumeMapper->SetInput( m_pData );

In this approach m_pData is a vtkStructuredPoints object which is filled
with a bunch of scalars (my radiation values). The problem is that I don't
really know how to set up the scalars in the correct order. 

I do it the following way but this works only if the dimensions of X & Y & Z
are the same.

    for( Iter = Data.begin(); Iter != Data.end(); Iter++ ) {
          Iter->GetPos( X, Y, Z);
          Val = Iter->GetVal();
          Index = X + Y * DimY * DimZ + Z * DimZ;    // calculate an index
from 3D coordinates
          
          pScalars->InsertScalar( Index, Val);

          if( Val < m_MinVal )
            m_MinVal = Val;
          if( Val > m_MaxVal )
            m_MaxVal = Val;
        }

        m_pData->GetPointData()->SetScalars( pScalars );   // connect to
test data
   }

If the dimensions are different then the whole picture looks scrambled.
Probably the calculation of the index from the voxel coordinates is wrong. If
somebody could give me a hint or point out a different way of doing it or any
other solution I'd be REALLY REALLY REALLY grateful!!!!

Thanks very much
Sepp

-- 
+++ GMX - Mail, Messaging & more  http://www.gmx.net +++
Bitte lächeln! Fotogalerie online mit GMX ohne eigene Homepage!