I am going to raise this from the dead because there is no real documentation. this is also one of the most un-intuitive ways of doing bone masking I have ever encountered. I much prefer just a simple list of bones. this system is powerful but really hard to understand at first.
This is using 4.17.2
ok so I have a simple character, here is a snippet of the hierarchy:
spine
spine1
spine2
LeftShoulder
(left arm bones)
RightShoulder
(right arm bones)
Neck
Head
Here is his base animation and the blend animation i want to mask. I have rotated his spine over and rotated his shoulders up, and rotated his head and neck back. these are both fed into the layered blend per bone node.
ok so lets make our goal to JUST mask the spine.
here I have added a branch filter to my layered blend per bone. The results are “spine” and all of its children are using the funky anim:
now lets add another entry into our Branch Filters. enter Spine1 and set its blend depth to -1
Now we are getting somewhere! with this setup we are only applying the blend animation to the first spine link (Spine). the -1 acts like a “block”.
lets try another, here we change our “block” form spine1 to LeftShoulder. Now all children of the first spine bone are using the blended animation except our left shoulder and entire left arm (all the children of the left shoulder)
lets finish this up. remember that our plan was to only apply the blend animation the spine bones. here is how we would set this up:
Now we are only applying the blended animation to our spine. Is this the “correct” way to use this node? I have no idea. this is just how i have figured out how to use it, if someone sees this thread and has a better answer i would be extremely happy to be corrected!