Model to Model Distance Parameters

What are the differences between the parameters in model to model distance? By that I mean, what’s the differences between absolute closest point, signed closest point, and closest point? How do these differences effect the shape model created?

Since nobody seems to know this off hand, the best would be if you could have a look at the source code and get this information from there. We would appreciate if you shared what you’ve found so that we can add it to the module documentation.

@bpaniagua

I had a student use this module in the past, so I know that signed distance is negative when one model is inside the other. I don’t know about the closest points computation. The module is based directly on a vtk filter according to this docs page:
https://www.slicer.org/wiki/Documentation/Nightly/Extensions/ModelToModelDistance

VTK is well documented so you can read the docs for the filter to see what it does.
https://vtk.org/doc/nightly/html/classvtkDistancePolyDataFilter.html

A bit late reply:

  • closest point correspondence does not assume that there is already an established correspondence between the meshes, but generates the correspondence on the fly (matching points as corresponding if the distance is closest across all points).
  • signed means that the sign of the distance (negative vs positive) depends on whether one surface is inside the other (like Lauren mentioned). This is computed relative to the target model, i.e. if the source surface at a given point is inside the target surface then that distance will be negative
  • corresponding_point_to_point: this means that there is already an established, index-wise correspondence (e.g. by using SlicerSALT to generate corresponding surfaces) and the distance is computed between points at the same index in each mesh.