Ground Mesh Expansion

PathEngine includes includes code for very robust 'minkowski expansion' of a ground mesh, so that collision and pathfinding operations can then be performed against the agent origin without taking the agent shape into account.

The result of minkowski expansion is normally a minimal boundary representation that does not include ground attributes or height detail, and that is then mapped back to the surface of the original ground mesh for whenever these details need to be looked up.

In cases where minkowski expansion is desired, but with a more complete ground mesh representation for the result (e.g. to take advantage of PathEngine's robust expansion operation whilst generating ground mesh data for an external application), this is provided through iPathEngine::buildUnobstructedSpaceGround().