debugShowBoundingVolume does not show correctly

Dear all,
I want to show bounding volume of an picked object.
This is sandcastle link

I picked red polygon but bounding volume draw on both red and blue?
What is the problem with bounding volume?

My best guess is this is because while they are two separate entities, they are one underlying primitive (batched, for performance reasons). I was going to suggest a better approach is to compute the entity’s bounding volume separately and render that, but it seems you’ve figured this out in this thread:

https://groups.google.com/d/msg/cesium-dev/BSXl9QhzlXs/_zbWc20FBAAJ

Hopefully that approach solved your problem!