We’re Moving to the Left-Up-Forward (LUF) Coordinate System

General Announcements
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With the v36.00 release, we’re transitioning to the Left-Up-Forward (LUF) coordinate system. This replaces the previous Forward-Right-Up (FRU) setup from v35.00 and brings us in line with industry standards used by 3D tools like Autodesk® Maya® and Universal Scene Description (USD).

All transforms in UEFN—including those from Actors* and Verse—now use LUF coordinates. Rotations are expressed using Euler angles applied in LUF order, rather than Yaw/Pitch/Roll style.

What does this mean for your projects?
Your existing content won’t be broken or modified.
You will notice changes in how transform values appear in the editor for existing projects, including environments created with Scene Graph.
The update may require you to adjust your mental model when interpreting coordinate values and rotations.

We understand this may require some adjustment, but comprehensive resources are available for a better idea of what’s going on: Left-Up-Forward Coordinate System: Left-Up-Forward Coordinate System in Unreal Editor for Fortnite | Unreal Editor for Fortnite Documentation | Epic Developer Community

*Actors definition: https://dev.epicgames.com/documentation/uefn/unreal-editor-for-fortnite-glossary#actor

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Hey all! To prepare for v36.00 and LUF coordinates, you don’t need to make changes to your code or content for your published islands to function properly.

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For more context about why this change is happening see Tim’s Tweet

“The best time to make this change would have been 1995, but I believe the second best time is now with the launch of Scene Graph in UEFN.”

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FAQ Here.

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Awesome!

BTW: The announcement doco has typo in the header.
Forward-Right-Up (FRU) is Changing to Left-Forward-Up (LUF)!

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@Flak Heads up: The above linked article’s header still has a typo “Left-Forward-Up”.
thx

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Thank you so much, @Hicsy!

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@Flak A possible typo in line 1935 of the Verse.digest.verse:

    #  * *yaw* is right-handed rotation about the Down axis,

ps. there are HEAPS of new efficient + useful calculations in this section now since v3600 - thanks so much!! <3
also cool: we can now extend rotation & vector2/3 with our own helper functions yeww!

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(post deleted by author)

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Thank you!