Distance display conditions

[mramato]

I would like to be able to make primitives turn on and off based on distance from the camera. I imagine that in 3D and Columbus view this would be straight line distance. But in 2D it would translate to just difference in height.

For batch primitives, such as BillboardCollection, I would like each item to turn on and off individual instead of distance to the entire batch.

[pjcozzi]

Display conditions in general should support KML Regions.

CC #873

[pjcozzi]

Initial work is in the display-condition branch.

[pjcozzi]

The display-condition branch is now part of the gfx branch, which has a few other odds and ends I am working on. The display condition is really just d604157.

[mramato]

Should we just close this since it will be superseded by the 3D Tiles work?

[pjcozzi]

3D Tiles works for the massive dataset use case. This is for the individual primitive/entity. Won't we need it for KML?

[mramato]

Good point, we can leave it open.

[pjcozzi]

See #3835 for the start of a DistanceDisplayCondition in 3D models.

[pjcozzi]

OK to close this?