Curves compressed from additive animations will not interpolate correctly if they have two keys in a row with the same value. The second key will be ignored, leading to the curve interpolating earlier than intended. See linked UDN for more information, and a potential fix. 

Steps to Reproduce
  1. Duplicate the ThirdPersonWalk animation from the ThirdPersonExample project
  2. Add a new curve to the animation
  3. Add three keys to the curve with time 0.0 value 1, time 0.38 value 1.0 and time 0.41 value 0.0
  4. Set the animation's Additive Animation Type to Local Space
  5. Set the Base Pose Type to Skeletal Reference
  6. Compress the animation with the compression scheme: remove linear keys
  7. Setup the ThirdPerson_AnimBP to play the new additive animation, and print out the value of the curve from step 2 on animation update.
  8. Play in editor


The values printed to the screen will interpolate from 1 to 0 from the start instead of staying at 1 for about half a second.

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ComponentOLD - Anim
Affects Versions4.214.23
Target Fix4.26
CreatedOct 16, 2019
ResolvedAug 11, 2020
UpdatedAug 12, 2020