Enable function of ImprintGeometry operation.
Uncomment code that actually calculated distance.
Set number of threads for vtkMultiThreader, so code actually runs on multiple threads.
Use vtkImageData::TransformIndexToPhysicalPoint() so image coords
are properly located in world space.
Add 'Imprint Distance' option to allow seeing the distance field, instead of just the presence/absence of the input mesh.
Edited by Aron Helser