has
Per-frame flag set by earth.worldwind.shape.RealtimeSightline.makeDrawable when a visible sightline is enqueued. Read by Ogc3dTilesProgram.get (and any other program that splices earth.worldwind.layer.sightline.SightlineReceiverGlsl) to pick the sightline-aware variant up front. Independent of DrawContext.sightlineState, which is populated later during the depth pass.