This is primarily so we can have a Visitors and a Books sphere off-screen in BoH
FromPath should now be a property on Spheres.
In the case of Thresholds, if FromPath is specified for a greedy threshold, the GreedyAngel will only look for targets in the sphere returned by the path.
(It's up to a Sphere implementation what FromPath actually does in other cases. It might later mean e.g. only draggable from a sphere that satisfies FromPath)
This is primarily so we can have a Visitors and a Books sphere off-screen in BoH
FromPath should now be a property on Spheres. In the case of Thresholds, if FromPath is specified for a greedy threshold, the GreedyAngel will only look for targets in the sphere returned by the path.
(It's up to a Sphere implementation what FromPath actually does in other cases. It might later mean e.g. only draggable from a sphere that satisfies FromPath)