Design Director- Categories

In the Design Director, "Categories" refers to groups of objects - 2D, 3D, cameras, etc. You can insert a category into the Design Director in order to have easy access to zooming, visibility, and other properties of the object group.

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All object groups you add to the Design Director will appear in the lower pane. The lower pane contains the following options:  

ZoomTo: Zooms to the extents of the objects.
Visible: Displays or hides the objects.
Color: Sets the objectsobject's pen color.
Add To Category: Adds the selected object to the category.
Remove From Category: Removes the selected object from the category.