Is there an atlas functionality in UE5.3

Development Programming & Scripting UI
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Is there an atlas functionality in UE5.3? We hope to combine multiple images on the UI into a single image to optimize performance.

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[Image Removed]When setting the atlas in Sprite, it freezes for a while and then triggers a crash.

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Hello [mention removed]​,

Thanks for the report. I was able to reproduce the issue locally by enabling Sprite Atlas Groups and assigning an Atlas Group to a Sprite asset. In my tests, this causes the editor to hang and crash in 5.3, 5.6, and a recent UE5-main source build. The same workflow does not occur in 5.2, which suggests this may be a regression introduced in 5.3.

I’m currently looking further into this and I’ll get back to you as soon as I have an update.

Best,

Francisco

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5

Hello [mention removed]​,

Thanks again for the report. I’ve now submitted this issue internally to the engine team. Once it becomes public, you’ll be able to track its status here: Unreal Engine Issues and Bug Tracker (UE\-358149)

Regarding the cause, this is an infinite loop in the editor. In UE 5.3 and later, assigning a Sprite Atlas Group to a PaperSprite causes UPaperSprite::PostEditChangeProperty to be triggered twice. The first call corresponds to the user-driven change, while the second call occurs during atlas rebuild propagation and comes through with a generic property change event. During this second call, the sprite attempts to rebuild the atlas again, which re-triggers the same code path. This repeats indefinitely, resulting in an editor hang and eventual crash.

As a temporary workaround, the loop can be prevented by guarding the atlas rebuild logic in UPaperSprite::PostEditChangeProperty so that it is skipped when the change type is EPropertyChangeType::Unspecified, similar to how rebuilds are already skipped for interactive changes. For example:

if (PropertyChangedEvent.ChangeType != EPropertyChangeType::Interactive &&
    PropertyChangedEvent.ChangeType != EPropertyChangeType::Unspecified)
{
  // Existing logic for atlas rebuild
}

This should avoid the infinite loop and let you set the Atlas Group property. This workaround was taken from the following forum post:

https://forums.unrealengine.com/t/paper2d-sprite-atlas-group-issue-in-5-3-2/1772474/9

Please let me know if you need anything else on this. Otherwise, I’ll go ahead and close the case.

Best,

Francisco

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