Assume you are an architect, and you want to check against the structural engineering drawings in order to see what is different between two drawings so that you can allow for that in your design. Drawing Compare is a new feature in AutoCAD 2019 that allows you to check out the differences between drawings. You can see the DWG Compare command in the Compare panel at the end of the Collaborate tab.
“DWG Compare” also can be found in the Drawing Utilities in the Application Menu.
When you want to compare two drawings, it is important to make sure that you have them in place before you start the command. If two drawings are exactly identical, but in different places in the model spaces, the DWG Compare command will not work correctly. You can run DWG Compare without any drawings open. When you click on the DWG Compare command, it opens up the DWG Compare dialog box, so that you can choose two drawing files to compare.
Basically anything that is specific to the first drawing file, will be highlighted in green, and anything specific to the other drawing file, will be highlighted in red. So the contents that are highlighted in these colors are different between the drawings, and all the contents that are common to both of the drawings will be in gray.
When you compare the two drawing files, AutoCAD creates another drawing file with the comparison results. The results file will open in a new file tab with a long name consists of the word “Compare” at the begining, then followed by the names of the two files respectively. As the comparison results are presented in an AutoCAD drawing file, you can normally save or plot it for further checking or revision.
You will also notice that the Compare contextual tab comes up on the ribbon with three panels: Comparison, Compare Filter, and Change Set.
The Comparison panel has “Draw Order” which changes the draw order of the compared drawing files. It also has icons for opening other files to be compared. The Comparison panel also has “Drawing Information”, by which the information for each of the two drawing files can also be accessed and copied to the clipboard or inserted in the comparison drawing. Default comparison colors can also be changed by clicking on the color icons and choosing other colors for the highlighted differences and the common objects as desired.
In case you need to change the color of the revision clouds, just change the color of their layer (named 0-Markups).
The second panel in the Compare tab is “Compare Filter” which has only “Text” and “Hatch” switches. They allow you to turn on or off the ability to compare text and hatch between the two drawing files. By default “Text” is on and “Hatch” is off, but you always can turn on or off whichever you want. Bear in mind that “Text” compares single-line text but does not compare multi-line text.
The third and last panel in the Compare tab is “Change Set” which has options for changing the shape and margin of the comparison marker. You can switch revision clouds on or off by “Revision Cloud”. You can also change their shapes (Polygonal/Rectangular) and amount of margins around them to be bigger or thinner. Lastly, the white arrows are used for zooming to the highlighted differences one by one.