Managing Model Annotations
When you create a 3D model, you simultaneously create various references useful for detailing the model in a drawing, including dimensions, reference dimensions, geometric tolerances, symbols, axes, and others. When you import a 3D model into a 2D drawing the 3D dimensions and stored model information maintain parametric associativity with the 3D model but, by default, they are invisible. You can then selectively choose which 3D model information to show on a particular view, which is the concept of showing and erasing.
Items that you make visible are referred to as shown. These "shown" dimensions are associative to the 3D model in both directions, so you can use them to drive the model dimensions from within the drawing environment.
Items that are not visible are referred to as erased. The erased 3D detailing items are maintained within the 3D file database, unless you delete them from within the 3D model. You cannot permanently delete these 3D detailing items from within the drawing environment. Erased items stay erased from session to session.
You can show or erase all stored 3D model information at any time during the detailing process.
As you show and erase detailing, remember you can only show one instance of a 3D detail item for a feature per drawing. You can move a shown 3D detail item from one view to another, for example, from a general view to a detailed view where it is more appropriate. To provide dimensioning for views when shown (driving) dimensions are "used up" in other views, or if you need to create a dimension that was not used to define the 3D geometry, insert an additional (driven) dimension.
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You can also show or erase entire drawing views. This does not delete them from the drawing. Erasing views can help in repainting large drawing files. On the Layout tab, click Erase View.
For short term invisibility, you can use the Hide and Unhide shortcut commands available from selected parts in the model tree. Hidden objects do not stay hidden from session to session however, and erased objects do.
You can erase or unerase model cosmetics. Select cosmetics or a feature that owns cosmetic on the Model Tree, right-click, and use the Erase Cosmetic command available on the shortcut menu to erase cosmetics. Similarly, select erased cosmetics or a feature that owns erased cosmetic on the Model Tree, right-click, and use the Unerase Cosmetic command available on the shortcut menu to unerase cosmetics. Additionally, you can select a view from the Drawing Tree or graphics window that contains cosmetics, right-click, and use the Erase Cosmetic command on the shortcut menu. Similarly, you can select a view that contains erased cosmetics, right-click, and use the Unerase Cosmetic command.