Undo and redo

The keys

• Press Cmd/Ctrl + Z to undo.
• Press Cmd/Ctrl + Shift + Z to redo, or Ctrl + Y.

Cmd/Ctrl means Cmd on a Mac and Ctrl on Windows or Linux. Click away from a text box before using these keys to change the model; while the box has focus, the keys go to the text you're editing.

What one step takes back

Deleting a selection is one undo step, even when several objects go together. Undo restores the deleted objects and selects them again.

While editing a floor, ceiling or roof outline, Undo takes back the last outline change and keeps the outline open. Redo reapplies that change.

During a gesture

Outside an outline session, if you're carrying a selection to move it or placing an object, the first history shortcut cancels the active gesture. Once it has ended, use the shortcut again to step through the model's changes.