Efficient transfer of dynamic 3D world model data

A system in a mobile platform creates a three-dimensional world model from sets of volume elements organized into sets of volume elements of increasing size and converted into an octree data structure. The system receives a request for a map of a specific, limited region and at a specific, limited level of detail and produces a reduced three-dimensional world model to conform to the limited region and level of detail. The reduced map is transmitted to the requesting platform and periodically updated. The map may be reduced by categorizing the lowest level of volume elements according to the worst case of any constituent volume elements. Alternatively, the system may indicate in the lowest level of volume elements whether the receiving platform would benefit from an increased level of detail.