getDisplayReach

How far this bone's own cubes reach from the point its display stands on, in blocks at scale 1, through any cube rotation. Moving, turning or scaling the bone keeps its cubes within this distance, times the bone's scale, of that point, which is what makes a ridden display safe to cull. The display stands on the model centre (see BoneTransforms.globalPoint); the centre of the cubes' box is measured too in case the two ever differ. 0 for a bone without cubes.