Problem with determining point based on surface UV

Grasshopper
1

I’m in the process of prototyping an algorithm to create a clipping/cutting volume based on the scene bounding box (inflated) and a set of clipping planes in the rhino document.

The basic idea is:

  • intersect planes with (inflated) box.
  • generated surfaces Surfaces from intersection curves.
  • split box with surfaces
  • cap the new breps Closed breps
  • generate checkpoints Points for Surfaces
  • keep Closed breps that contain Points

The problem is that for some intersection surfaces generation of Points yields some that don’t lie oriented around the middle of the surface as highlighted in the attached screenshot. How can I fix this?

edit: Note that rotating the selected clipping plane to some degree will result in proper point, and thus clipping volume, generation

selected component highlights wrong point
image.png1916×835 458 KB

point moved along normal
image.png890×585 43.9 KB

point from half-UV
image.png890×585 56.4 KB

uv_point_problem.gh (28.8 KB)
clippingvolume_gh.3dm (198.5 KB)

Thanks in advance for any useful information.

2

I’ve found a much better way to generate the check-points Points:

image
image.png1062×650 49.9 KB

3

In case someone is wondering (and even if not), here is how it looks like:

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