Blender Git Commit Log

Editmesh Undo:

User Info:
Pressing UKey in mesh edit mode now undoes only last step. Undo can save
upto 64 steps of undo info. This is configurable under User Prefs->
Edit Methods. The default is 32. High numbers of undo steps use a
lot of memory, since each step stores a copy of the mesh.

Shift-U redoes the last undone step (Undoes the undo.)

Alt-U brings up a menu of possible steps that can be undone. Selecting
an item on the list undoes that item plus all items before it on the list.
The top selection "Undo All" is identical to the old Ukey. It undoes
all editing since entering Editmode, even if all regular undo steps are
used up.

Undo info is only saved for one object at a time. You can leave and re-
enter editmode for the same object, and all undo steps for that object are
preserved. Undo info for an object is lost once a different object is
edited.

Coder Info:
In order for undo to work, a checkpoint save has to be made. This is
done with a call to undo_push_mesh("name of step"). This should be done
after the last quick abort for a function (typ. the
"if (G.obedit==0) return;", or similar). the undo_push_mesh() does alter some
flags, so don't try to be too tricky and call undo_push_mesh() too late.
The step name is what shows up in the undo_menu. The name "U" is reserved.