Ground primitive artifact on iPad

[OmarShehata]

Sandcastle link. This works fine on desktop, and mostly fine on iPad:

Until you zoom in a bit on iPad, you can see a seam very similar to the one in #8205 that moves with the camera that will cut out pieces of the polygon:

I believe it's related to #8205 because I can see the same seam across the 3D Tileset, but using that branch the seam is fixed on the 3D Tileset but remains on the ground polygons.

[lilleyse]

How many frustums are being drawn in that view. It might not be #8205 if it's just one.

@likangning93 might have a better idea.

[lilleyse]

Oh except this is iPad which may not support log depth, so there are probably multiple frustums.

[OmarShehata]

Yes, I suspect there's multiple frustums because iPad doesn't support log depth. Although I can't reproduce the issue on desktop by turning off log depth. I updated the Sandcastle to turn off log depth and include the inspector. You can see it's using 2 frustums:

And at that camera distance that "shreds" the polygon, if you show the frustum geometry and rotate around, you can see it's when the frustum plane intersects that building: