Never mind. I see it in 1.14.
Unfortunately, our billboards have to be pinned at the center of the image.
So even clamped to the ground, the exact alt will still have half of the icon in the ground.
Clamped to ground, and pinned to the bottom is the only way to achieve that treatment of the icon always being above ground.
So let me ask you this. Would it be possible to extend/add to the logic that sets transparency and size based on camera distance?
My thought is to make he altitude of the billboard increase as the camera is farther away, to make sure that the icon continues to appear above the ground completely. (by moving it up as the camera moves away).
The only other option is to adjust the hotspot of the icon as the camera tilts, so that when you are tilted all the way down the hotspot is on the bottom. And when you are topdown, it is in the center.