TerrainEye

directionreadonly

Eye direction in the body's rotating axes.

distancereadonly

Eye distance from the body's center.

radiusreadonly

reliefreadonly

Peak-to-datum relief, meters.

Bounds the shell [radius − relief, radius + relief] that ground can occupy. It is used for the distance and for the horizon and nothing else, so an over-estimate costs patches and an under-estimate cuts off a peak — surface.maxElevation is the generator's own bound and is the right number.