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ProModel allows definition of resource points for crane resources on envelope nodes to achieve the three dimensional look for "lowering the hoist" upon arriving at a node. Since cranes can only have one unit, only the first resource point for any crane at any node is meaningful. Also, ProModel only uses the resource points if the crane resource arrives at the node to perform a task. In other words, the hoist does not lower if the crane arrives at a node to park or just ends up there after a bump.
In general, once ProModel makes a match between a resource request and a resource of the requested type, the resource is allocated for that job and the simulation engine does not go on looking for other matches that can actually reach to the requester sooner. Since cranes blocking other crane resources is a common phenomenon in multi-bridge envelopes, extra care should be used while designing the active operation zones and resource request logic in such models.