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- Rotate the model by left button of mouse
- Select the cavity/cavities by drawing a rectangle over the part of the cavity with a right mouse button pressed
Selected cavities will be highlighted by red colour:
- To move selected cavity to approved class click on button to approve
Here you can see how approved cavity looks like:
- To move selected cavity to rejected class click on button to reject
Blue zones are rejected cavities, green - approved, yellow - undefined status:
- Sometimes it is useful to select all zones by button
(or Ctrl+A) and move them to some class (for example, reject all zones) - To drop selection press 'Esc'
- Also there is a special mode (so-called scissors mode) of selection instrument. By activating it with button
, you may select only the part of the zone and move to the appropriate class 
Here is a short video demonstration of working with the instrument:
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