renderMode

Selects which phases this drawable runs. The sightline shapes enqueue two drawables per frame: RenderMode.DEPTH_ONLY in BACKGROUND so the depth cube and DrawContext.sightlineState are populated before any embedded-receiver fragment shader runs (3D tiles need this), and RenderMode.OVERLAY_ONLY in SURFACE so terrain gets tinted after opaque receivers have rendered. RenderMode.DEPTH_AND_OVERLAY preserves the legacy single-drawable path for callers that don't split the work.