Modifies followObject in-place. Invoked after position is resolved each frame.
Called once at drag start and again whenever the drag context resets (e.g. multi-touch → single-pointer transition). Capture any object snapshot (position, rotation, scale) you need to hold fixed during the drag. Constraints that need no dynamic initialization may omit this method.
Used by SnapToSurfacesDragStrategy for two-pointer (multi-touch) drags. Each frame
MultiTouchDragHandleraims the snap ray from the pointer origin(s) through the current two-finger grab midpoint (see setRay); apply() casts that ray into the scene and places the follow object so its bounding-box contact face rests on the hit surface with the object origin at the hit point — the same "snap to what the pointer points at" semantics as the single-pointer surface raycast.Only injected into the constraint pipeline for multi-touch; the single-pointer path continues to use SnapToSurfacesDragStrategy.update (pointer ray + drag plane intersection) unchanged.