Sculpt mode dimension changes don't Undo #38427

New Issue

Tom Cloney · 2014-02-01T00:25:58+01:00

Tom Cloney commented

2014-02-01 00:25:58 +01:00

Windows 8.1
NVIDIA Quadro FX 570
Broken: Blender 2.69.0 r60995

In Object mode, add a mesh cube. Use the SubSurf modifier in Simple mode to give it some detail
(this isn't directly involved in the problem, but makes it easier to see).
Switch from Object mode to Sculpt mode. Note the dimensions of the cube.
Use any tool to add some material to the mesh, using a single stroke. The dimension
corresponding to the face you added to will increase to reflect the added material.
Use Ctrl-Z to undo the stroke. The dimension doesn't change back.

When you go back to Object mode, the inflated dimension remains, which messes
things up if you later rely on the original dimension. In other words, the size listed
in the dimension panel no longer represents the actual size of the object.

By contrast, this isn't the way changes in Edit mode work. If you modify the vertices
of a mesh and then Undo, the dimensions change to reflect the Undo. Since Sculpt
mode is basically a wrapper for the same sorts of things you might do in Edit mode,
its Undo behavior should be the same (I only mention this to head off a specious
argument that this behavior is somehow a feature).

Workaround: When you return to Object mode, you can use Ctrl-Z there to Undo the
effects of the entire Sculpt session. It would be better to fix Sculpt, though, as the
current situation makes it easy to introduce dimensional discrepancies without being
aware of it.
SculptUndoBug.blend

Windows 8.1 NVIDIA Quadro FX 570 Broken: Blender 2.69.0 r60995 1) In Object mode, add a mesh cube. Use the SubSurf modifier in Simple mode to give it some detail (this isn't directly involved in the problem, but makes it easier to see). 2) Switch from Object mode to Sculpt mode. Note the dimensions of the cube. 3) Use any tool to add some material to the mesh, using a single stroke. The dimension corresponding to the face you added to will increase to reflect the added material. 4) Use Ctrl-Z to undo the stroke. **The dimension doesn't change back.** When you go back to Object mode, the inflated dimension remains, which messes things up if you later rely on the original dimension. In other words, the size listed in the dimension panel no longer represents the actual size of the object. By contrast, this isn't the way changes in Edit mode work. If you modify the vertices of a mesh and then Undo, the dimensions change to reflect the Undo. Since Sculpt mode is basically a wrapper for the same sorts of things you might do in Edit mode, its Undo behavior should be the same (I only mention this to head off a specious argument that this behavior is somehow a feature). Workaround: When you return to Object mode, you can use Ctrl-Z there to Undo the effects of the entire Sculpt session. It would be better to fix Sculpt, though, as the current situation makes it easy to introduce dimensional discrepancies without being aware of it. [SculptUndoBug.blend](https://archive.blender.org/developer/F75737/SculptUndoBug.blend)

Tom Cloney commented

2014-02-01 00:25:58 +01:00

Changed status to: 'Open'