import { Vector3 } from "three" ; import { MapView } from "./MapView" ; import { MapViewUtils } from "./Utils" ; /**
 * The default value for camera movement throttling, in milliseconds.
 */ const DEFAULT_THROTTLING_TIMEOUT = 300 ; /**
 * The `CameraMovementDetector` class checks for changes in camera position and orientation, to
 * detect continuous movements without the animation mode activated in  MapView . If the
 * interaction is not continuous enough, you can use a throttling timer to reduce the number of
 * callbacks.
  export class CameraMovementDetector { private m_lastAttitude ? : MapViewUtils . Attitude ; private readonly m_lastCameraPos = new Vector3 ( ) ; private readonly m_newCameraPos = new Vector3 ( ) ; private m_cameraMovedLastFrame : boolean | undefined ; private m_throttlingTimerId ? : number = undefined ; private m_movementDetectorDeadline : number = 0 ; /**
     * Initializes the detector with timeout value and callbacks.  MapView also provides
     * events for client code to be notified when these cues occur.
     *
     *  param m_throttlingTimeout param m_movementStartedFunc param m_movementFinishedFunc constructor ( private readonly m_throttlingTimeout , private m_movementStartedFunc , private m_movementFinishedFunc ) { if ( this . m_throttlingTimeout === undefined ) { this . m_throttlingTimeout = DEFAULT_THROTTLING_TIMEOUT ; } } param mapView checkCameraMoved ( mapView , now ) { const newAttitude = MapViewUtils . extractAttitude ( mapView , mapView . camera ) ; const newCameraPos = mapView . camera . getWorldPosition ( this . m_newCameraPos ) ; if ( this . m_lastAttitude === undefined ) { this . m_lastCameraPos . copy ( newCameraPos ) ; this . m_lastAttitude = newAttitude ; return false ; } const cameraMoved = ! this . m_lastCameraPos . equals ( newCameraPos ) || newAttitude . yaw !== this . m_lastAttitude . yaw || newAttitude . pitch !== this . m_lastAttitude . pitch || newAttitude . roll !== this . m_lastAttitude . roll ; if ( cameraMoved ) { this . m_lastCameraPos . copy ( newCameraPos ) ; this . m_lastAttitude = newAttitude ; } if ( cameraMoved !== this . m_cameraMovedLastFrame ) { if ( cameraMoved ) { this . movementStarted ( ) ; } this . m_cameraMovedLastFrame = cameraMoved ; } if ( cameraMoved ) { this . m_movementDetectorDeadline = now + this . m_throttlingTimeout ! ; this . startMovementFinishedTimer ( now ) ; } return this . m_cameraMovedLastFrame ; } /**
     * Reset the saved camera position. Next time checkCameraMoved is called, it will return
     * `false`.
     */ clear ( mapView ) { const newCameraPos = mapView . camera . getWorldPosition ( this . m_newCameraPos ) ; this . m_lastCameraPos . set ( newCameraPos . x , newCameraPos . y , newCameraPos . z ) ; const newAttitude = MapViewUtils . extractAttitude ( mapView , mapView . camera ) ; this . m_lastAttitude = newAttitude ; } /**
     * Force change of camera position. Next time checkCameraMoved is called, it will return `true`.
     */ forceMoved ( ) { this . m_lastCameraPos . set ( Number . NaN , Number . NaN , Number . NaN ) ; } /**
     * Returns `true` if the camera of this  MapView is currently moving. In this case the
     * `m_movementFinishedFunc` is waiting to be called after the throttling timer runs out.
      get cameraIsMoving ( ) { return this . m_throttlingTimerId !== undefined ; } /**
     * Disposes resources and kills the throttling timer.
     */ dispose ( ) { this . removeMovementFinishedTimer ( ) ; this . m_movementStartedFunc = undefined ; this . m_movementFinishedFunc = undefined ; } /**
     * Returns `true` if the camera has moved in the last frame.
     */ get cameraMovedLastFrame ( ) : boolean { return this . m_cameraMovedLastFrame === true ; } private movementStarted ( ) { if ( this . m_movementStartedFunc !== undefined ) { this . m_movementStartedFunc ( ) ; } } private movementFinished ( ) { this . removeMovementFinishedTimer ( ) ; if ( this . m_movementFinishedFunc !== undefined ) { this . m_movementFinishedFunc ( ) ; } } private startMovementFinishedTimer ( now ) { if ( this . m_throttlingTimerId === undefined ) { const remainingTime = Math . max ( 0 , this . m_movementDetectorDeadline - now ) ; this . m_throttlingTimerId = setTimeout ( this . onDeadlineTimer , remainingTime ) as any ; } } private readonly onDeadlineTimer = ( ) => { this . m_throttlingTimerId = undefined ; const now = performance . now ( ) ; if ( now >= this . m_movementDetectorDeadline ) { this . movementFinished ( ) ; } else { this . startMovementFinishedTimer ( now ) ; } } ; private removeMovementFinishedTimer ( ) { if ( this . m_throttlingTimerId !== undefined ) { clearTimeout ( this . m_throttlingTimerId ) ; this . m_throttlingTimerId = undefined ; } } }