Legacy Reference

Setting up a Skeleton

The system requires certain joints to determine where a character is aiming. You can use existing joints in the skeleton or add extra joints to improve your setup.


The joint names that are referenced for the attributes in the .chrparams file should match the names of the joints in your skeleton. The joint names don't have any specific naming requirements.

You can add the following types of joints.

  • ParameterJoint – A joint that indicates the aim direction, with the y-axis forward.

  • StartJoint – A joint that indicates the positional center of the aim. Orientation is not important because only position information is used from this joint. For more stable results, use a less animated joint that is less influenced by other joint animation. For example, use a joint that is connected to the root joint (the first skeleton joint, which is placed at origin 0,0,0).

  • ReferenceJoint – (Optional) A joint that indicates the forward direction of the character with the y-axis pointing forward. If a value is not specified, the joint at index 1 (usually the pelvis) is used. This joint is primarily used for characters in cinematics because they might have an offset on top of the root joint. In this case, don't use the root joint as the reference joint. Instead use the joint that acts as the translation or position driving joint to determine the point that is underneath the character.