Tech Note: Root motion is not extracted from montages on linked anim instances

Jul 29, 2021.Knowledge

Summary: Root motion is only extracted from montages on the main anim instance and not any linked anim instances

Potential Impact: Limited: Only anim BPs that use linked anim instances from which root motion is expected to be generated will be effected. Root motion generated within the anim graph (ie. root motion from everything) is not affected.

Solution: There is a fix for the issue in the shelved CL 16084511. After applying these changes, root motion can be extracted from a linked anim instance. However, be aware that the changes do not support root motion generation from multiple anim instances within the same anim BP. Instead the first anim instance that is found which generates root motion is the one that will be used to drive the motion of the character. Because of this limitation, we do not plan to integrate this change into a release and instead we plan to fully support root motion generation from multiple linked anim instances in future.