Function _onPinchStart

modules/core/src/controllers/controller.ts:643–655

(event: MjolnirGestureEvent)

  // Default handler for the `pinchstart` event.
  protected _onPinchStart(event: MjolnirGestureEvent): boolean {
    const pos = this.getCenter(event);
    if (!this.isPointInBounds(pos, event)) {
      return false;
    }

    const newControllerState = this.controllerState.zoomStart({pos}).rotateStart({pos});
    // hack - hammer's `rotation` field doesn't seem to produce the correct angle
    pinchEventWorkaround._startPinchRotation = event.rotation;
    pinchEventWorkaround._lastPinchEvent = event;
    this.updateViewport(newControllerState, NO_TRANSITION_PROPS, {isDragging: true});
    return true;
  }

  // Default handler for the `pinchmove` and `pinchend` events.
  protected _onPinch(event: MjolnirGestureEvent): boolean {