Updated on 12/24/2019
DoubleCAD User Manual Publication
DoubleCAD User Manual : Display
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The options on this page that is relevant to 3D is in the Display section. For the remaining options, see Display Options.
Draw form-building edges: When checked, the entire structure of 3D objects is shown. When not checked, the minimum number of edges needed to show the object will be displayed.

With form-building edges

Without form-building edges

Note: You can make selected edges non form-building with the Edit Tool. See Edit Tool in 3D.