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[edit] Copy Location Constraint

[edit] Description

Copy Location forces the object to have the same location as its target. When this constraint is used on a bone and another bone is the target, a new button--labeled Local--appears next to the X Y Z buttons. Using the local button causes the local translation values of the target to be given to the constrained object. In rest position, all bones are at the local location of (0,0,0).

[edit] Options

Target

Object of which location to copy.

X Y Z

Axis to constraint. Use - to invert it.

Head/Tail - With Bone targets only

A number from 0.0 to 1.0 that represents the place on the target bone to use for the Copy (0.0 = the bone's root; 1.0 = the bone's head)

[edit] Example

Left: Using global space. This is the default behavior; it's what happens when the local button is not activated. Right: Using local space, with local button activated.

In these last two images, the constrained bone (shown in green) is actually a child of the root bone (the bone at the beginning of the chain). This demo shows possible uses for the location constraint in a rig. Note that the green bone still inherits rotation from the root because the root is its parent. This is by design though; the green bone could be the child of any of these bones, or none of them.