Gh project

Projecting point objects in the Z direction onto a geometric object, some output point objects may detach from the projected geometric object. I have found a workaround by jittering the geometric object in the Z direction to avoid overlapping between the point objects and the edges of the geometric object. My question is, based on what is the position of the point object determined when it detaches from the geometric object?"
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the points on the external edge are coincident already with the brep you are projecting on, I think that is the culprit

if you move the points “down” a little bit first, then project them, everything works correctly:

111 (1) (21.9 KB)

Yes, you’re absolutely right。But I’m wondering about those points that don’t have a normal projection. What determines their current position?

I’ve looked up explanations about tolerances, angular tolerances, and so on, but I still don’t understand what determines the positions of these outlier points