threePointDepthTestDistance
The distance from the camera, within which, billboards with a Billboard.heightReference value of HeightReference.CLAMP_TO_GROUND or HeightReference.CLAMP_TO_TERRAIN are depth tested against three key points. This ensures that if any key point of the billboard is visible, the whole billboard will be visible. When set to 0, this feature is disabled and portions of a billboards behind terrain be clipped.
This setting only applies when a billboard's Billboard.disableDepthTestDistance value would otherwise allow depth testing—i.e., distance from the camera to the billboard is less than a billboard's Billboard.disableDepthTestDistance value.