Geometry Node: Stretch profiles around turns in Curve to Mesh Node.
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Authored by Shan Huang (yemount) on Sep 27 2022, 9:14 AM.

Details

Reviewers

Campbell Barton (campbellbarton)
Hans Goudey (HooglyBoogly)

Maniphest Tasks

T80979: Account for curvature in curve to mesh node

Summary

Stretch profile curves around turns in curve to mesh. This is done by

compute the desired stretch amount to keep the connecting edges parallel to the curve segment.
compute a matrix to scale the profile by the amount around its main position, and ONLY in the direction of the curvature.

This addresses T80979.

Diff Detail

Repository

rB Blender

Branch

fix-bevel (branched from master)

Build Status

Buildable 23963
Build 23963: arc lint + arc unit

Event Timeline

Shan Huang (yemount) requested review of this revision.Sep 27 2022, 9:14 AM

Shan Huang (yemount) created this revision.

Harbormaster completed remote builds in B23963: Diff 56169.Sep 27 2022, 9:14 AM

Cleanups

Harbormaster completed remote builds in B23964: Diff 56170.Sep 27 2022, 9:18 AM

Iliya Katueshenock (Moder) added projects: Nodes & Physics, Geometry Nodes.Nov 15 2022, 4:34 PM

Bruno (brunochartier) added a subscriber: Bruno (brunochartier).Nov 20 2022, 6:48 PM

Capture profile stretching transformation as a matrix.

Harbormaster completed remote builds in B24754: Diff 57863.Nov 20 2022, 11:49 PM

Shan Huang (yemount) edited the summary of this revision. (Show Details)Nov 20 2022, 11:57 PM

Shan Huang (yemount) added reviewers: Campbell Barton (campbellbarton), Hans Goudey (HooglyBoogly).

Shan Huang (yemount) mentioned this in T80979: Account for curvature in curve to mesh node.Nov 21 2022, 12:06 AM

Shan Huang (yemount) added inline comments.Nov 21 2022, 12:15 AM

source/blender/blenkernel/intern/curve_to_mesh_convert.cc
204	Diagram about the math:
216	This is a bit more matrix multiplication than I'd like... but at least we only need to compute it one per turn, and it's quite neat for readability imo to capture the transform in a matrix. Alternatively I can project the pre-stretch point onto the axes defined by (tangent, curvature, up), scale the curvature vector, and sum everything back up. (Roughly like this: https://developer.blender.org/D16076?vs=on&id=56170) Let me know if that is more preferred.

Hi Shan, just tested diff 57863, it is working with "flat" curve however not really with a 3D "maze" where some profile/bevel rotation appears on some corners.