Share Email Facebook Twitter LinkedIn Control the Visibility of Datums Topics in this section About Datum Visibility in Project Views When you resize model (3D) datum extents, you can control in which view they are visible. About Visibility of Non-Perpendicular Datums in Views If a datum element (such as a reference plane) is not perpendicular to a view, then the datum element does not display in the view. About Visibility of Arc Grids in Views In plan views (such as floor plans and ceiling plans), you can define grid lines that are arcs rather than straight lines. Datums with Gaps Video: Control Visibility Datums To control how levels and grids display in project views, adjust their 2D and 3D extents. Best Practices: Datum Extents When working with datum extents, follow these best practices. Parent topic: Tools and Techniques