Certain information in a design is used repeatedly, whether it be grids, plans, furniture or structural elements. This information could be drawn in each file but if changes need to be made, they will need to be amended in all the files. Referencing provides a way of creating a single file which can then be “externally referenced” into multiple files. If the reference information changes, it will be reflected automatically in all the files it is referenced into.
References allow a design to be split up so that multiple people can work on parts of the design at the same time. This keeps file sizes down and keeps all files up to date with changes.
Working with References
References are managed from an External References palette. To display the palette, from the Ribbon View tab > Palettes panel, click the External References button.
Command line: To display the External References palette from the command line, type “XR” and press [Enter].
At the top of the palette, the current open file will be shown. Any attached references are listed below the open file. Select a reference to show the properties of the reference in the Details section of the External References palette.
AutoCAD can attach the following file types as references:
- AutoCAD DWG files
- MicroStation DGN files
- Autodesk DWF files
- Adobe PDF files
- Most common image formats including TIF, JPG and GIF
Attaching References - DWG
From the External Reference Palette, click the drop-down next to the Attach DWG button to choose the type of attachment you required.
Click Attach DWG... This will show the Browse window.
Locate your reference and click OK. The Attach External Reference dialog box will open.
Choose the Reference Type from Attachment or Overlay.
Overlay brings in the chosen reference file and ignores any references attached to that file.
Attachment brings the reference and any references attached to it.
Scale, Insertion point and Rotation can either be set from the dialog box or you can specify on screen when you place the reference.
Note: References would normally be attached at a scale of 1:1 full size at the 0,0 origin. This ensures that when referencing multiple files, they overlay the information correctly e.g. the wall outlines align correctly with the grid.
Path type allows you to choose between Full path, Relative path and no path.
Full path Uses the full path e.g. C:\WhiteFrog\Design.dwg
Relative path Uses the path required to get back to the source drawing file e.g. \WhiteFrog\Design.dwg
No path Removes the path and searches only the folder the Drawing file is filed in.
When attaching references, AutoCAD always uses the currently set UCS. This means if you have changed the location or orientation of the UCS the references won’t align over the top of each other.
A UCS is a “User Coordinate System” which defines the angle of the XY plane you are working in. Normally this is set to “World”, meaning that the XY plane is horizontal with an origin at 0,0. Defining a User Coordinate System rotates the XY plane, making it more convenient for working to other orientations.
You should normally set the UCS to World prior to attaching a reference.
From the Ribbon View tab > Coordinates panel, click the World button.
References are similar to any other geometry and can be moved, rotated and copied using the normal AutoCAD modify tools.
Once a file is attached, select a reference in your file and right-click to show the available options.
Open Opens the file in AutoCAD.
Attach Allows the attachment of another reference file.
Unload Unloads the reference from your file so it is not visible. It is still attached.
Reload Reloads the reference and updates its display with any changes.
Detach Detaches the reference from your file.
Bind... Copies the reference into the current file as live information.
Edit Xref in-place...
The contents of an External reference can be modified in the current file without having to open that file. Select the Edit Xref in-place option. The Reference Edit dialog box will open. Your selected reference will be highlighted. Click OK.
All the information in your file will fade except for the selected reference file.
Make any required changes to the reference file.
Once you have completed, click Save on the External Reference context sensitive tab > Edit Reference panel.
Note: A context sensitive Ribbon tab is one that will show only when you have a specific tool selected. In this case the Edit Reference tool is active so the Edit Reference panel is shown on all the tabs.
You will be prompted to save changes. Click OK to accept or Cancel to exit without saving changes.
Once a reference is attached, you may not want to show all the information on the reference file. You can use the Clip option to hide part of the reference file.
First you need a closed Polyline to clip your reference to.
To clip a reference, select the Clip Xref option from the right-click menu. AutoCAD will prompt:
[ON/OFF/Clipdepth/Delete/generate Polyline/New boundary] <New>:
Typing “N” for new will then prompt:
[Select Polyline/Polygonal/Rectangular/Invert clip] <Rectangular>:
Typing “S” for Select Polyline will then allow you to select a closed polyline to use as the clip boundary. A separate clip frame based on the selected Polyline is created on the current layer. The original Polyline can then be deleted leaving the clip frame visible.
To Delete a Clip Xref
To delete a clip, select the Clip Xref option from the right-click menu. AutoCAD will then prompt you for:
[ON/OFF/Clipdepth/Delete/generate Polyline/New boundary] <New>:
Typing “D” for Delete will delete your reference clip.
The reference frame can be manipulated to adjust the boundary of the clip. Use the grips to manipulate the frame to obscure or reveal the reference as required.
Clicking the cyan arrow will cycle between showing only the contents inside or outside of the frame.
The display and plotting of clipping frames can be controlled using the XCLIPFRAME system variable. Type XCLIPFRAME at the Command Line. You will be prompted:
Enter new value for XCLIPFRAME <2>:
The following settings can be used:
0 Clipping frames are not displayed or plotted. When a clipped external reference is selected, the frame will temporarily appear.
1 Clipping frames are displayed and plotted.
2 Clipping frames are displayed but are not plotted. This is the default setting.
By default External References appear 70% faded when attached to a file. The level of fading can be controlled in the Options dialog box > Display tab in the Fade Control section.
Xref display Controls the amount of fading of references in the file.
In-place edit and annotative representations Controls the amount of fading, when editing a reference, of all other references and the current file.