When you reference an external drawing in a host drawing, the resulting Xref is like a block insert in the host drawing.
- this means you cannot modify (e.g. Stretch) individual objects of an Xref when the host drawing is the active drawing.
- in AutoCAD Release 14 you had to Open the xref drawing file if you wanted to make changes to the individual objects in an Xref.
Host drawings may contain many different Xref drawing files that are stored in different locations of a network.
- you must Close the host drawing in AutoCAD Release 14 before editing Xref drawing files (R14 is not an MDI application).
- finding the right Xref file to change (Save, Close, Open, Change, Save, Close, Open etc.) was tedious in AutoCAD R14.
AutoCAD 2000 now has a new Edit in place feature that lets you overcome these Xref editing limitations.
- Xrefs are STILL like block inserts in the host drawing file so you cannot modify individual objects in them directly.
However, now you can use the Refedit command to temporarily transfer Xref objects into a special working set in the host drawing.
- you can modify this Refedit working set using regular AutoCAD commands (such as Stretch).
- you can Add new objects to (or Remove objects from) the set using Refset which transfers objects back & forth between files.
- when you are finished with the desired changes you must use the Refclose command to Save or Discard your changes.
All of these commands & options are accessible from the Refedit toolbar (opens automatically when you run the Refedit command).
When you run the Refedit command you must select a reference and a dialogue box will then appear.
- the object you select may be a nested xref (an xref which is attached to the xref that is attached to the host)
- you can navigate in a tree or pick the Next button to select the desired nesting level for nested xrefs.
As with the Bind option of Xref, there is always a chance of naming conflicts if you transfer objects from one drawing to another.
- for example, both drawings may contain a layer called WALLS but use different layer definitions in each drawing.
- check Enable unique layer and symbol names to avoid conflicts by adding a special prefix (e.g. $0$) to blocks & layer names.
Attribute definitions are not normally displayed by default but you can check Display attribute definitions for editing if required
- then attribute definitions in the xref are available for editing along with selected reference geometry.
When you pick OK to close the dialogue box you are prompted to select nested objects to add to the Refedit working set.
- you should select the objects that you plan to modify.
- then the Refedit toolbar will appear (if it was not already open) and you can proceed to make the required changes.
Refedit can be used to change block definitions which can be practical even if you do NOT use reference files.
When you change an Xref in a host you could be changing hundreds of other host drawings if they reference the same Xref.
You can specify whether or not Xrefs can be modified with Refedit. make the desired Xref the active drawing, use the Options ommand and select the Open and Save tab.
- then uncheck Allow other users to Refedit current drawing to protect that drawing against edits made in host drawings.
You can also change Refedit fading intensity using Options.
PRACTICE EDITING REFERENCES IN PLACE
1)Close any open drawings from the previous exercise.
2)Open the T202_14.dwg drawing in your personal folder.
3) Pick Insert + External Reference. Select T202_15.dwg in your personal folder and pick Open to continue. Uncheck all Specify On-screen boxes and pick OK.
Now the walls of this small office appear in the active (host) drawing as an Xref
- this might be what an interior decorator would do to experiment with various furniture layouts.
- there could also be other people who reference the same floor plan to generate other drawings (such as office lighting plans).
4) Pick Modify + In-Place Xref and Block Edit + Edit Reference to access Refedit. When prompted on the Command line to Select reference, pick one of the walls from the T202_15.dwg external reference near P1. Then pick OK in the resulting dialogue box to continue.
5) When you are prompted to Select nested objects pick in empty space near P2 then pick near P3 to select the six LINEs shown highlighted below with an implied crossing window. Then press <enter> to continue.
Select nested objects: (pick in empty space near P2)
Specify opposite corner: (pick near P3)
6 entities added
Select nested objects: ↵
Use REFCLOSE or the Refedit toolbar to end reference editing session.
Now you can modify these six LINE objects in the external reference file as if they were actually in the current drawing.
6) Pick Modify + Stretch and follow the dialogue below to move the right wall 120 inches (ten feet) to the left.
Select objects to stretch by crossing-window or crossing-polygon… Select objects: (pick in empty space near P1)
Specify opposite corner: (pick near P2 for an implied crossing window)
Select objects: ↵
Specify base point or displacement: –120,0↵
Specify second point of displacement: ↵
The Refedit toolbar remains opened on-screen so you can easily
- Add objects to the Refedit working set
- Remove objects from the Refedit working set
- Discard changes made to the external reference
- Save changes back to the external reference.
7) Pick the Add button of the Refedit toolbar to use the Add option of the Refset command & select the sofa near P1. Then press <enter> to add the sofa block insert to the Refedit working set.
8) Pick the Remove button of the Refedit toolbar to use the Remove option of the Refset command & select both wall LINEs near P2. Then press <enter> to remove these two wall LINEs from the Refedit working set.
The sofa is no longer faded but the walls you just removed are faded (you may have to adjust fading in Options to see this; see page 50)
- the sofa BLOCK INSERT will be transferred from the host to the external drawing file.
- and the two wall LINEs you removed from the set will be transferred from the external reference drawing to the host.
- but these changes will be implemented ONLY after you pick the Refedit toolbar button on the far right of the toolbar.
9) Pick the last Refedit toolbar button on the right of the toolbar to Save the changes back to the external reference file. Then pick OK in the AutoCAD alert box when you are warned that all reference edits will be saved.
If you examine the AutoCAD text window you may have a better idea as to what just happened to the host and reference drawing files.
Enter option [Save/Discard reference changes] <Save>: _sav
The following symbols will be added to Xref file:
The following symbols will be permanently bound to the current drawing:
3 objects added to T202_15
2 objects removed from T202_15
1 xref instance updated
U02_6 redefined and reloaded.
The SOFA block was transferred to the external reference drawing
- so the SOFA block definition and FURNITURE layer symbols were added to the external reference drawing.
The two LINEs were added then removed from the external file so the net addition to the external reference file is 1 (the sofa) insert.
- the wall LINEs from the xref were bound to the host drawing and a new layer name ($0$WALLS ) was generated in the host.
- if Enable unique layer and symbol names was NOT checked (in step 6) the layer name would have been just “WALLS”.
10) Pick Insert + Xref Manager. Select the T202_15 Xref and pick the Unload button to unload this Xref from the host drawing file without losing any of the insertion parameters. Then pick OK.
The sofa is no longer in the host drawing because it was transferred to the external reference drawing file.
- there are also two wall LINEs in the host drawing that were transferred from the external reference drawing file.
11) Save the changes to the current drawing and Close the file.