Outline Group of Points

The following definition finds the boundaries of a point cloud using edge lengths of the delauney component. By creating a box around the points which is larger than any possible connection between the points themselves, the outermost points can be found be measuring their relative edges in the delauney mesh. In a slightly clunky step, the end points of these edges are then matched to their original points, and duplicates created by the mesh are removed using the kangaroo plugin – when I find the script I wrote that does the same thing I will update the definition so you dont need kangaroo.

The points are then sorted using a script which iteratively searches through the points and finds the smallest neighboring angle. This allows the points to be connected avoiding overlaps produced by random list orders.

Depending on your point cloud you may need to increase the size of the containment box: the setting in the definition is 3 but the larger the number the more this works.

Outline Points Definition

~ by ledatomica on May 26, 2010.

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