To Turn Off Automatic Regeneration
By default, the display is updated with a repaint when you change from one window to another. Because model-to-drawing repaints and regenerations can be time consuming for larger files, you have the option to turn off the automatic regeneration function.
If you set auto_regen_views to no, you can selectively update the drawing by choosing > 
Update Drawing View. With this setting, you can only update the drawing to reflect changes in the 3D model. You cannot regenerate the model from the drawing as you can with the yes setting.
Update Drawing View. With this setting, you can only update the drawing to reflect changes in the 3D model. You cannot regenerate the model from the drawing as you can with the yes setting.