How can I access the final blend samples and weights of a blendspace from a custom anim node?

Development Programming & Scripting
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TLDR: Does anyone happen to know how I can access the final blendspace weights/samples from the UBlendSpace class?

Over the last few days, I’ve been attempting to make a distance-matching blendspace node. This is meant to be similar to a BlendSpaceEvaluator, but it will take in distance rather than time. The below picture shows the (nonfunctional) node I’ve made so far.
DMBSp

I’ve already made a proof of concept, the result of which is shown in the below video, and it works well, but that was without the use of a specialized node. It’s cumbersome to iterate with that approach though.

My plan is the following:

  1. From the my custom Anim Node Behavior struct (FAnimNode_BlendSpaceDistanceMatch), grab the relevant BlendSamples determined by the UBlendSpace class, which I think are those that have a weight higher than ZERO_ANIMWEIGHT_THRESH.
  2. From those samples, get the current play time using the DistanceCurve.
  3. Normalize that time based on each BlendSample’s total play length.
  4. Sum to get the weighted normalized time: WeightNormalizedTime = NormalizedTimes.[1] * BlendSample.Weight[1] + NormalizedTimes.[2] * BlendSample.Weight[2] + ... or something like that.

My current dilemma is figuring out how to get the BlendSamples and corresponding weights. From what I can tell, this information is hidden away in an FBlendSampleData struct that I can’t seem to access (unless I’m missing something).

Does anyone happen to have any suggestions?

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Bump.

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To get the blend samples, you can use the GetSampleFromBlendInput function within the UBlendSpace class. So, for example, given a UBlendSpace* MyBlendSpace, you can get TArray<FBlendSampleData> BlendSampleData by doing the following: MyBlendSpace->GetSamplesFromBlendInput(ClampedBlendInput, BlendSampleData, TriangulationIndex, true), where the ClampedBlendInput is of type FVector and represents the parameterized position within the BlendSpace — and this can be acquired by doing FVector ClampedBlendInput = MyBlendSpace->GetClampedAndWrappedBlendInput(GetPosition()).

Essentially, to get the sample data, you could do something like the following:

FVector ClampedBlendInput = MyBlendSpace->GetClampedAndWrappedBlendInput(GetPosition());
int32 TriangulationIndex = 0; // this can be stored elsewhere
TArray<FBlendSampleData> BlendSampleData;  
MyBlendSpace->GetSamplesFromBlendInput(ClampedBlendInput, BlendSampleData, TriangulationIndex, true);

I hope that helps. I do the above in my Animation Matching Suite plugin when I apply distance matching to BlendSpaces.