Ever wanted to constrain your orbit to only the X or Y axis in Revit?  Here is one way to do it:

  1. Download DragLock and run it
  2. In a Revit 3D view, hold down Shift, then your Left Windows Key, and then your Middle mouse button
  3. Starting dragging horizontally or vertically – your mouse movement is constrained to one axis only.

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Disable Mouse Movement on One Axis – Tech Salsa