Link limb sets up a limbs position in the limb hierarchy.
Limbs are arranged in an hierarchy - that means the limbs are arranged in parent child relationships like the branches of a tree. For example, the shoulder of a character could be the parent of the upper arm and thus the upper arm is the child limb of the shoulder. The upper arm could be the parent of the lower arm so the lower arm is the child of the upper arm etc to the hands and even to the fingers if there are that many limbs.
Using link limb sets up the hierarchy in DBC unless the structure is already set up in an external 3d modeler and you are using a loaded 3d object. However you can add additional limbs as long as the count is in sequence - then you could link more limbs to the model.
Whenever you use ADD LIMB to add a limb to a model or primative, the limb is linked to limb 0. You use link limb to link it to another already existing limb.
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