The "Get Tangent at Distance Along Spline" node returns incorrect tangent values compared to "Get Location and Tangent at Spline Point", where the spline point is at the same distance along the path.

If querying a point at a certain distance along a spline, its is expected to return the same location and tangent as querying a point placed at that same distance along the spline.
Getting the tangent by distance returns a different value. Trying to create a spline mesh using that tangent will end up with at distorted and/or twisted mesh.

This issue was reported in 4.19.2 (CL-4033788) and reproduced in 4.18.3 (CL-3832480), 4.20 (CL-4212847), and Main 4.21 (CL- 4217587)

Steps to Reproduce
  1. Download and open the attached project
  2. Drag the Blueprint 'SplineTest' in the Viewport
  3. Look at the printed values in the Output Log for Distance Points and Spline Points

Results: The two sets of value are different.

Expected: The two sets of values are the same.

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Won't Fix
Affects Versions4.
CreatedJul 18, 2018
ResolvedAug 18, 2021
UpdatedAug 18, 2021
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