Compare Files

To compare files, PowerWeb displays a unique viewing page that shows the renditions of the selected documents. The two files can be two revisions of the same rendition file or two similar but unrelated renditions that you want to compare visually. The page allows you to see either of the renditions alone or a simultaneous view of both renditions that displays the additions, deletions, and unchanged objects between the two files in symbolic colors:

Green: Additions
Red: Deletions
Black: Unchanged

To compare files, PowerUser displays a unique multi-pane window. Two of the panes show two files side-by-side. The two files can be two revisions of the same source or rendition file or two similar but unrelated files that you want to compare visually. The area of the files shown in the two panes are synchronized with one another. When you change the view of one file, the view of the other file is changed automatically to match the first file. This makes it easy to compare files without adjusting the views, sizes, and positions of separate windows.

If the files being compared are supported vector (CAD) graphics files, the lower-right pane shows the additions, deletions, and unchanged objects between the two files in configurable colors. The lower-left pane contains options to change the colors. This graphical representation of changes is valuable for quickly determining the differences between two complex files. You can print a hard copy of the differences and also generate a report of the non-graphical differences between two files, for example, layer names, system variables, and so on.

Comparing renditions is supported by the built-in PDFTron viewer.
In Meridian 2021, comparing renditions using the built-in PDFTron viewer does not automatically recalculate the difference after you pan the document. To recalculate the difference, click Refresh.
Graphics that have been moved but that are otherwise unchanged are considered by Compare as a deletion from one document and an addition to the other document.

PowerWeb Procedures

To visually compare two renditions:

Select two documents that you want to compare.
Choose between two options:
- Right-click one of the documents, point to Document, and then click Compare Renditions.
  
  The Compare Renditions page appears.
- In the Document ribbon, in the Action group, click Compare Renditions.
  
  The Compare Renditions page appears.
Use the options of the page as described below.
Click Exit.

Compare Renditions page options
Option	Description
Keep in sync	When enabled and you switch from one rendition to the other, the viewing area remains the same so that you don't have to manually match the viewing area of one rendition to the other. When disabled, the viewing area is not synchronized so that you can easily view different areas of each rendition and switch between them.
Rev.<lowest>	Displays only the first rendition.
Rev.<highest>	Displays only the second rendition.
Difference	Displays both renditions simultaneously with the colors indicated by the legend in the bottom right corner of the page.
Refresh	Refreshes the current view to show any changes that have been made to renditions since you first opened the page.
Swap	Reverses the comparison order of the renditions.

PowerUser Procedures

Use Ctrl+click to select one of the following:
- Two similar documents from a Navigation view
- Two revisions of the same document from the Revisions dialog
- One document in a briefcase to compare with its original in the vault. Meridian Enterprise will automatically select the original document
Click the Compare button .
Use the tools in the toolbar or the shortcut menu to change the view of the documents.

All panes remain synchronized on the same area of the documents.

Automatic pane synchronization is not supported for all formats in all viewer plug-ins. When working with an unsupported combination, click the Synchronize button to manually synchronize the views.

Use the browse buttons or corresponding shortcut menu commands to load different revisions of the same documents, different documents from the vault, or documents that reside outside the vault for comparison.
Click options or type values using the descriptions in the following table.

Compare window options
Option	Description
Show additions	Displays graphics in the right document that do not exist in the left document. Select a color to display additions from the list.
Show deletions	Displays graphics in the left document that do not exist in the right document. Select a color to display deletions from the list.
Show unchanged	Displays graphics that are identical in both documents. Select a color to display unchanged graphics from the list.
Report	Displays a report of the invisible changes between the two documents. The information can be saved to a file where it can be printed. Not available for raster documents. This option is only available if the current viewer is the ICViewPlugin viewer.
Print Differences	Prints the graphics in the Compare Result pane to a printer.
Compare property values	Compares and optional updates the property values of one document with the property values of another document. To compare the property values of the two documents, see Compare Document Property Values.