Define rotation axis for manipulation with mouse.
 
 
Rotate by All axes
Rotate view along the direction of the mouse around center of viewport window. 
  
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Rotate by Vertical axis
Rotate view around the vertical axis on the viewport window. 
  
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Rotate by Horizontal axis
Rotate view around the horizontal axis on the viewport window. 
  
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Rotate by Normal axis
Rotate view around the normal axis on the viewport window. 
  
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