Subject: Attaching underlays created in other file formats

When you attach an underlay, a picture representation of the file’s contents is inserted into the drawing. An underlay is similar to an image and different from an external reference in that it cannot be linked and automatically updated.

You can attach underlays using files that have the following formats:

   PDF format — Portable document format viewable using Adobe® Acrobat® Reader® and Adobe® Acrobat. The PDF format uses the .pdf file extension.

   Autodesk® DWFä format — Autodesk Design Web Formatä (used with .dwf files) is used to distribute a drawing for others to view in a Web browser, review, and edit using free Autodesk software and tools. The DWF format uses the .dwf file extension.

   DGN format — Drawing files used with Bentleyâ Microstationâ. The DGN for­mat uses the .dgn file extension.

   PCG format — Point cloud files used by Autodesk® software and tools. The PCG format uses the .pcg file extension.

   RCP/RCS format — Point cloud files. The RCP/RCS format uses the .rcp or .rcs file extension.

   IFC format — BIM files in the Industry Foundation Classes format for building and construction data.

   RVT/RFA format — BIM files used by Autodesk Revit® for building and con­struction data.

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Attaching a PDF underlay

Attaching a DWF underlay

Attaching a DGN underlay

Attaching a point cloud underlay

Attaching a BIM underlay

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