About Underlays

You can underlay and snap to 2D geometry stored in DWF, DWFx, DGN, and PDF files.

Underlays are similar to attached raster images in that they provide visual content but also support object snapping and clipping. Unlike external references, underlays cannot be bound to the drawing.

You can underlay the following file types:

Use the Ribbon Contextual Tab to Work with Underlays

If you select an underlay when the ribbon is active, the DWF Underlay Ribbon Contextual tab, the PDF Underlay Ribbon Contextual tab, or the DGN Underlay Ribbon Contextual tab displays depending on the type of underlay selected. The contextual tab contains options for adjusting, clipping and displaying underlays. The ribbon contextual tab is dismissed automatically after the underlay is deselected.