Feature Request: Rotate Object About Arbitrary Point
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Rotate Object About an Arbitrary Point
When rotating an object about a remote point r, the correct transformation can be computed using the rotation matrix R (which you're already using for in-place rotation). After rotating, apply a translation by:
(I - R) * r
Where:
I is the identity matrix
R is the 2×2 rotation matrix
r is the point (in global coordinates) that you want to rotate around
This results in the correct affine transformation for rotation about a fixed external point, not just the object’s center.
It would be very useful to support this natively for tasks like pattern replication, mechanical design, and geometry scripting.
Thanks for considering it!
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@jpsimmons When the transform tool is active (first icon in the toolbox), the context panel will have this button.
This opens the transform options:
The second icon can enable or disable the center offset.
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The tooltips say to enable or disable the transform pivot point editing, which sounds like the right thing. I click on it and nothing happens, but it is highlighted in blue. How do I set the point of rotation and how do I rotate about it?
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@jpsimmons Once it is enabled, when an object is selected a red dot appears at the center. This can be dragged to set the center.
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@VectorStyler That works. Well. Can I set this to be default behavior? Like in "settings"?
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@jpsimmons That is the settings. Once turned on, it should stay on even after restart.
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@VectorStyler It does. And the pivot point snaps to gridlines if you set it to. Nice!