It is now possible to use the geometry of Meshes and/or Lattices as the target of a constraint. All you need to do, is to create a new Vertex-Group and assign all the points that you wish to use as the target, then type that name into the VG: field for the relevant constraints.
One of the cases where this is beneficial is when you need to copy the location of a vertex. Now you don't need to make extra vertex-parents for that.
Additional Notes:
* The code takes the average of the locations of the nominated vertices, and puts that in world-space for constraint solving (and regular space-conversion stuff).
* Currently, rotation and scaling of points is not taken into account. The rotation/scaling used is from the object's matrix. Hopefully, this will only be a temporary problem (will be fixed soon)
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