Skip to main content

Layer Overlay IC

Layer Overlay IC​

LayerOverlayInputController handles overlay tooling interaction:

  • selection controls
  • transform handles
  • interaction overlays synchronized with world camera

Typical setup​

import { LayerOverlayInputController } from '@flowscape-ui/core-sdk';

let overlayInteractionOwner: string | null = null;
const overlayController = new LayerOverlayInputController();

scene.inputManager.add(layerOverlay, overlayController, {
  stage: host.getRenderNode(),
  world: layerWorld,
  overlay: layerOverlay,
  emitChange: () => scene.invalidate(),
  getInteractionOwner: () => overlayInteractionOwner,
  tryBeginInteraction: (ownerId: string) => {
    if (overlayInteractionOwner !== null) {
      return overlayInteractionOwner === ownerId;
    }
    overlayInteractionOwner = ownerId;
    return true;
  },
  endInteraction: (ownerId: string) => {
    if (overlayInteractionOwner === ownerId) {
      overlayInteractionOwner = null;
    }
  },
});

Why ownership exists​

Overlay tools can compete for pointer control.

Ownership callbacks guarantee that one tool owns interaction at a time.

OverlayInputOptions API​

OverlayInputOptions currently exists as an empty type:

export type OverlayInputOptions = {};

This keeps the API symmetrical with world controller options and allows non-breaking expansion later.

Practical notes​

  • Keep ownerId stable for each tool.
  • Always release ownership in endInteraction(...).
  • Call emitChange() after overlay state mutations.

Next​