PlanetAt(x:Int, y:Int, [flag:Bool]):Int
Get planet by location.
Returns the Id number of the planet at position (x,y). When flag is True (nonzero, nonempty), returns the planet whose gravity wells are in effect at that place; when flag is False or not specified at all, returns only exact matches. If there is no such planet, it returns zero.
Since: PCC 1.0.18, PCC2 1.99.9