Rotation and counter-rotation should return an object to precisely the same position and orientation

If I rotate an object, say 45 degrees, then re-select that object and rotate it negative 45 degrees, the object ends up translated (ie not in the same position).

This can be quite annoying if the model was previously positioned precisely around an axis (it always is).

Why not just use undo? Sometimes Shapr3D crashes during the counter rotation, and sometimes I mistakenly return to the home screen and close the application with the model rotated, thereby losing the undo stack.

I cannot reproduce the problem neither in live or beta versions. Translation tools (move/rotate, rotate around axis) work for me.

The only way to end up with an offset, if you are not positioning your transformation center point to the original point. The default position of the transformation center is the center of mass, which is the same for both original and rotated object relatively to themselves, but those points are not in the same position if you compare it with the world coordinate system.

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This is what I mean. Perhaps I have a misunderstanding how this should work?

MacOS Monterey 12.6
Apple M2
Shapr3D Version 5.230.0 (4183)

I double checked it with the devs, so we are actually not using the center of mass currently (caused huge performance issues with calculations and we’ve changed it down the road), but the center of bounding box - it is a fall back solution. The good news is, that we are going to fix this, but not in weeks, it takes longer. Thanks for raising the issue again :pray:

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Thanks for the explanation.