Diffing Blueprints

Hi guys! Happy Tuesday to you all! We have a new post up on the blog](https://www.unrealengine.com/) today by engine programmer on diffing blueprints. Enjoy!
In an earlier post, we discussed asset diffing in Unreal Engine 4, but only briefly covered our tool specifically for diffing blueprints. We’re back today with a tutorial video designed to further explain the Blueprint diff tool.

As a refresher: “diffing” is where two files get compared side by side. The differences between the two files are highlighted for you, making them easy to spot. Without diffing, tracking down bugs and dissecting features can be a headache (especially with large, complex files).

Traditionally, diffed files are textual. However, with blueprints, a textual representation would not be especially helpful. That’s why we crafted our own blueprint diff tool. With it, every edit (nodes moved/added/removed, connections made or broken, pin values modified, etc…) is listed for you to see.*

The following video shows off the tool, and explains how to use it.

Thanks for checking it out! If you have any questions, be sure to let us hear your thoughts!

  • Note: In 4.0.1, the list of differences has the direction ‘sense’ flipped (e.g., it will say “Removed Node” when a node was added). This has already been fixed for future releases.

Good little tutorial Mike. It’s nice that this tool can diff 2 different blueprints as well, useful for local incremental copies.

Also a suggestion for the blueprint diff viewer itself. It would be helpful if we can have a button at the top left, to switch the docking of the 2 views from vertical to horizontal. Especially because unlike text diff tools (where you write a set of code statements in different lines), here in blueprint, we link a set of nodes from left to right, so I think even the default view would be better to be set to 2 views at the top and bottom instead of left and right. No need to say the left panel, can stay as it is at the left of the window in either view. Thanks.

Thanks for the feedback!

Good suggestion as well! I’ve logged a task so that we don’t forget about it. Anything to make the tool more usable; I agree that the vertical split is a little constrained.

Hi Mike,

We find this incredibly useful, do you know if there are any plans to extend functionality to merge blueprints together and then resolve the differences if there are any ?

At the moment we are kind of manually doing this (love the ability to copy nodes over different versions) and then forcing the update onto our perforce server, but this is not optimal, as you can imagine.



Looks like the video has gone without updating the post.

I’d also like to know if any merge functionality is in the works.

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