I want to add a note here (and I have to thank Ashley's above clarification for the hour or so I spent deriving this solution), but if you're loading a JSON object from a server, you'll want to make sure it's a 3-dimensional array, and that, for example --and this was my issue-- if you have a 2-dimensional array, you'll have to set it up as a 3-dimensional array anyway with all entries set on 0z. (E.g [123][45][0] in php will serialize correctly with json_encode() as opposed to [123][45]. Similarly, for a 1d array, you'll have to place all entries on the 0y 0z plane.