Also called Animation Channels or Animations Masks, track masks are an important feature for any character that needs to be able to do more than one thing at a time. For example, running and aiming or jumping and shooting!
HeroEngine Track Masks Editor
To open, press the "Track Masks Editor" button on the "Hero Character Tools" in the MAXScript Utilities panel for 3ds Max or click on the "Track Masks" icon on the HeroTools Shelf in Maya.
The Mask Editor button provides a means of adding animation masks to a rig (Biped or Max bones). A mask is a named animation channel. HeroEngine supports an arbitrary number of channels. Each animation channel can have animations played on it independently. The mask lets you assign which bones are part of this channel, and how much influence they have. All bones are automatically part of the default channel.
For example, you could mask off all the bones that comprise the upper body, or say the left arm and create a named channel for them. Then, in HeroBlade, you could have a wave animation play on just the left arm regardless of what other animations are playing on the rest of the body. By adjusting the weights, you can feather the arm's channel influence into the shoulder.
When the Mask Editor button is clicked, the following dialogue will appear.
To create a new Mask, type a name into the field and click "Add." The new mask will be added to the list of masks on the rig in the scene. Click "Apply to all" to apply the mask to the bones comprising the rig.
Mask settings can be edited on a bone by bone basis by selecting a bone and opening the Modify panel. All masks on the rig will be listed here followed by a number between 0.0 and 1.0 to indicate the amount of influence the mask has on the individual bone -- 0.0 meaning the bone is entirely excluded from the mask, and 1.0 indicating the bone is fully included.
The selection helper buttons allow you to quickly select bones which meet one of the six conditions in regards to the selected mask. The conditions filter for bones that: have an zero influence from the mask, have full (1) influence from the mask, have influence from the mask equal to the current value entered, and the inverse of those three (NOT zero, NOT 1, NOT the entered value).
When using 3DS Max Biped and attempting to create an UpperBody channel, the lowest spine bone, just above the pelvis, will affect the root-bone and consenquently the legs even when the lower body bones are set to "0" for UpperBody.
You can work around this by leaving the lowest spine bone set to "0" for an UpperBody channel and animating appropriately.