Displacement/Height maps?!

[Traggey]

The heightmapping in HPL is actually just Parallax Mapping, it just fakes depth in a texture but doesn't actually create any. HPL can not do anything like that for landscaping, your only option is to model it in your modeling package of choise, now depending on the method you use you CAN turn a heightmap into real geometry in maya and then export it to HPL, I have no clue how that would work in Maya since I don't use it myself, but I know it can be done.

For example in Max you would accomplish this using the ''displacement'' modifier.