How the Compare Feature Handles External References (XREFs)

Drawing files often contain references to other drawings or images. Those references, or dependencies, are simply an embedded record of the path to the referenced objects or files. In AutoCAD, reference files are more commonly referred to as XREFsDrawing files often reference other files, including other drawings, as well as plot styles, images, standards, and font files associated with the drawing. Those references, or dependencies, are simply an embedded record of the path to the referenced objects or files. (external reference files). Microstation uses the term reference files. Drawings containing a reference to other files are referred to as host drawings.

When comparing host drawings in Project Center, the Compare Results window list of changes indicates when the host file or any of its references have changed. If the host drawing has changed, the Status column shows Changed. If one of the host drawings external references has changed, the Status column shows Changed (XREF), as shown in the following example:

To see which of the external reference files changed, click Show Xref Change Details from the Tasks panel. If you initiate a graphical comparison, any changes in the referenced files will be displayed graphically in the Newforma Viewer as well.