Specifies the direction of the aim vector relative to the constrained object’s local space. The aim vector will align with the target vector, forcing the constrained object to orient itself accordingly. The default specifies that the object’s local rotation positive X-axis aligns with the aim vector to align with the target vector (1.0000, 0.0000, 0.0000).
Specifies the direction of the up vector relative to the constrained object’s local space. The default specifies that the object’s local rotation positive Y-axis will align with the up vector. In turn, by default, the up vector will try to align with the world up vector. Further, by default, the world up vector will point in the direction of the world space’s positive Y-axis (0.0000, 1.0000, 0.0000).
If you define the up vector to point in the same direction as the aim vector, the constrained object will be motion history dependent. For more information, see Motion history dependence effects.
Specifies that the up vector try to aim at the origin of a specified object instead of aligning with the world up vector. The world up vector is ignored. The object whose origin the up vector tries to aim at is called the world up object. You can specify the world up object with the aimConstraint MEL command (use -wuo flag). If no world up object is specified, the up vector tries to aim at the origin of the scene's world space.