Get height for locations on unloaded terrainquads

Hi all,

I’m experimenting a bit with TerrainGrid, and I want to get the heights of location on terrainquads that are not yet loaded/visible. Terraingrid’s getHeight() and getHeightmanHeight() methods seem unable to do this (as they only return NaN’s).
I thought that perhaps I could do it the following way:

[java]//the absolute location of the object
Vector3f worldTreeLocation = new Vector3f(x,0,z);

//the coordinates of the cell/tile/terrainquad where the object location lies in
Vector3f tileCoordinates = terrain.getTileCell(worldTreeLocation );
Vector3f cellCoordinates = Vector3f((float)Math.floor(tileCoordinates.x),0f,(float)Math.floor(tileCoordinates.z));

//location of the object within the cell
Vector3f localTreeLocation = worldTreeLocation.subtract(cellCoordinates.mult(new Vector3f(set.terrainScaleX,0,set.terrainScaleY)));

//retreiving correct terrainquad from the tileLoader and asking it for the height
y = terrain.getGridTileLoader().getTerrainQuadAt(cellCoordinates).getHeight(new Vector2f(localTreeLocation.x,localTreeLocation.z));[/java]

but this method appears to give wrong height values and also lot’s of NaN’s

is there some way to do what i want?

thanks

nobody any ideas?