Customizing The Image Diff Tool

In AtomSampleViewer, the registry key O3DE/External/DiffTool defines the absolute path of the executable that should be used to compare screenshot results after running tests from the Automation menu.

Here is a json snippet in $HOME/.o3de/Registry/bootstrap.setreg, that customizes the image diff tool to WinMerge:

{
    ... 
    "O3DE" : {
        "External": {
            "DiffTool": "C:/Program Files/WinMerge/WinMergeU.exe"
        }
    }
}

This registry key is not defined by default, so AtomSampleViewer will default to the following paths for each platform:

• Windows: C:\\Program Files\\Beyond Compare 4\\BCompare.exe GetDefaultDiffToolPath_Impl
• Linux: /usr/bin/bcompare GetDefaultDiffToolPath_Impl
• MacOS: /usr/local/bin/bcompare GetDefaultDiffToolPath_Impl

All default paths mentioned above relate to a software called Beyond Compare.