Exposing BlendSpace pin on AimOffset Node causes unknown blendspace error

The exact error is:
“BlueprintEditorCompileResults:Error: Error AnimGraphNode_RotationOffsetBlendSpace_8 references an unknown blend space”

This error emanates from ‘UAnimGraphNode_RotationOffsetBlendSpace::ValidateAnimNodeDuringCompilation’ because ‘Node.BlendSpace’ is NULL.

That property gets set to NULL within this block of code within ‘FAnimBlueprintNodeOptionalPinManager::PostInitNewPin’:

			if (bIsAnimationAsset)
				ObjectProperty->SetObjectPropertyValue(PropertyAddress, nullptr);

Clean sample project attached for immediate repro.

Repro steps:

  1. Open Additive Pin Bug project

  2. Open “BugRepro” Animation Blueprint

  3. Note that it is currently in error

  4. Uncheck ‘as pin’ checkbox for the Blend Space property

  5. Compile that Animation Blueprint. The error goes away when the node is able to use its internally specified Blend Space that is not exposed as a pin.

  6. Check it again to expose the pin

Result: Compile Error comes back. Feeding a variable that matches the blendspace set in the node makes no difference

Expected: For the node to accept Blend Space pin input without compile error

Our goal is to be able to feed a UAimOffsetBlendSpace1D variable into that pin. This works fine for Blendspace Player using nonadditive offsets, but not for UAnimGraphNode_RotationOffsetBlendSpace.


[link text][2]

Got a possible fix to this that involves changes to the engine to make UAnimGraphNode_RotationOffsetBlendSpace read pins the same way that UAnimGraphNode_BlendSpacePlayer does.

I attached those fixes as a zip to this post. Please let me know if these get integrated into the engine. I’d rather have Epic’s official fix than have to manage another engine mod whenever I pull down new versions.

Edit: Looks like this was not addressed in 4.15. I’ve updated my fix for 4.15 making it very easy to diff and replaced the original attachment with the 4.15 version.

Yeah can we please get this in the engine?, we really need this.

Phew, well you just saved me a massive headache. I hope this is officially addressed in the engine soon.

Can confirm this bug exists in UE4.14.3. I haven’t upgraded to UE4.15 yet. Hopefully they will fix this soon. Kind of a pain in the tookus to work around it. I can live without it for now but eventually I’m gonna need them to have this fixed. Thanks for the attachment. I’d use it but I don’t want to commit to anything until Epic has a chance to actually respond to this bug.