Unconsistent XY planes direction along 3D curve

Grasshopper
1

hi community,

I don’t know why it does that, but when I evalute a 3D curve and orient a plan along the tangent direction of the 3D line at certain points, it flip the XY axis of the plan… Which is anoying because I need the X axis (or Y) always pointing upward.

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STR_definition_R6_v1.gh (21.8 KB)

So the triangle I build from theses planes are inverted sometimes…

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Best,
-CC

2

Hi @LeGaulois,

The plane is flipping where the curvature changes. This can be expected if the plane is calculated from tangent and curvature vectors. Best to use Curve.PerpendicularFrameAt, which will prevent this.

– Dale

2 Likes
3

Thanks for pointing that out @dale ! I used the component Perpendicular frame instead and manage something.
-CC