Can I analyze the thickness of a stl model, and then get a color map.

The distance between the two sides of an object.

# How to analyze the thickness of the model

“Thickness” is not a very well defined term for models (surface meshes), but for shell-like meshes it is probably not too difficult to estimate it robustly and accurately.

Potential approaches:

A. Extract medial surface and estimate thickness as 2x of distance from medial surface. There are various ways of computing these in Slicer. One possible workflow:

- Compute medial surface using
**Simple Filters module - BinaryThinningImageFilter**. - Compute distance map using
**Simple Filters module - DanielssonDistanceMapImageFilter**. Input is binary: Yes; Use image spacing: Yes. - Copy distance values from the distance map to model node using
**Probe volume with model**module.

Critical part is the medial surface extraction. If you find that it is not accurate enough then you may to use smaller voxel sizes for the model->labelmap conversion, or use a different medial surface extraction method (for example, medial surface extractor in VMTK or PowerCrust algorithm).

B. Implement a custom algorithm in C++. Something like this should be very easy to implement if you are already familiar with C++ programming using VTK: http://mmmanual.com/thickness/.