Free Electron Documented Operators
Common Operator Info
FE SurfaceMetricOp


Generates a point map based on a relationship between two surfaces.


An Input Surface is compared to a Contrasting Surface.


The output is a point map based on a selected Metric. Currently the only metric is a Signed Distance Function (SDF). The value of an SDF is the distance between the nearest point on the contrasting surface to a sample point on the input surface, where negative numbers indicate separation and positive numbers indicate penetration. The convention of positive and negative values can be reversed with Invert.

The generated point will have a float point attribute named by Value Attribute.

If Partition Input is selected, every unique value of a primitive string attribute specified by Partition Attribute will be treated as a separate UV space with an independent raster of data.

If Alignment Check is selected, the normal of each nearest primitive on the contrasting surface is compared to the sample point on the input surface. If the dot product of these normals is less than the Threshold, that primitive on the contrasting surface does not contribute to the results.

Each point map raster is generated with evenly sampled UV locations of a given Width and Height. The results are limited to Min and Max values.


(FE alpha) prototype
tested in Houdini

Web page, Copyright 2008-2021, Free Electron Organization