viewer.scene.clampToHeight giving wrong output

**i have loaded a terrain on top of the globe. To calculate height of the cursor i am subtracting the cursor coordinates from the viewer.scene.clampToHeight (cursorPoint). I am getting the wrong results. The result is not continuous it is varying in discrete manner like 0.4m, 6.4m,12.3 mts. ****The point is on the ground it is showing 0.4m height above ground. **I observed that the viewer.scene.clampToHeight result is varying itself to get that discrete output. Iam not getting the reason behind this wrong results.

I observed that when i am tilting the surface upto tilt nearer to zero then i am getting the correct results.

Have you tried using clampToHeightMostDetailed? clampToHeight will use whatever data is currently loaded, whereas the mostDetailed version will load the highest LOD to get the height:

I have objects to exclude in the clamptoHeight. When I am working with clamptoheightmost detailed that objects are not getting excluded.

How to load the terrain in highest level of detail??

This sounds like a bug. The objects to exclude should work the same way for both functions. Can you reproduce this issue on Sandcastle?