bug: fix unsafe usage of static variables

examples/src/utils/CustomCameraManager.ts

@@ -1,3 +1,4 @@
+import { Plane, Vector3 } from 'three';
 import * as THREE from 'three';
 import { OrbitControls } from 'three/examples/jsm/controls/OrbitControls.js';
 import pull from 'lodash/pull';
@@ -19,6 +20,7 @@ export class CustomCameraManager implements CameraManager {
   private _controls: OrbitControls;
   private readonly _cameraChangedListener: Array<CameraChangeDelegate> = [];
   private _stopEventHandler: DebouncedCameraStopEventTrigger;
+  private readonly cameraManagerHelper = new CameraManagerHelper();
 
   constructor(domElement: HTMLElement, camera: THREE.PerspectiveCamera) {
     this._domElement = domElement;
@@ -119,7 +121,7 @@ export class CustomCameraManager implements CameraManager {
 
   update(deltaTime: number, boundingBox: THREE.Box3): void {
     this._controls.update();
-    CameraManagerHelper.updateCameraNearAndFar(this._camera, boundingBox);
+    this.cameraManagerHelper.updateCameraNearAndFar(this._camera, boundingBox);
   }
 
   dispose(): void {

viewer/packages/camera-manager/src/CameraManagerHelper.ts

@@ -2,18 +2,54 @@
  * Copyright 2022 Cognite AS
  */
 
-import { Box3, PerspectiveCamera, Plane, Quaternion, Vector3 } from 'three';
-import range from 'lodash/range';
 import { fitCameraToBoundingBox } from '@reveal/utilities';
+import range from 'lodash/range';
+import { Box3, PerspectiveCamera, Plane, Quaternion, Vector3 } from 'three';
+
+type NearAndFarPlaneBuffers = {
+  corners: Vector3[];
+  cameraPosition: Vector3;
+  cameraDirection: Vector3;
+};
+
+type CameraFarBuffers = {
+  nearPlane: Plane;
+  nearPlaneCoplanarPoint: Vector3;
+};
 
 /**
  * Helper methods for implementing a camera manager.
  */
 export class CameraManagerHelper {
   /**
+   * @deprecated usage of mutable static variables is unsafe
    * Reusable buffers used by updateNearAndFarPlane function to avoid allocations.
    */
-  private static readonly _updateNearAndFarPlaneBuffers = {
+  private static readonly _updateNearAndFarPlaneBuffers: NearAndFarPlaneBuffers = {
+    cameraPosition: new Vector3(),
+    cameraDirection: new Vector3(),
+    corners: new Array<Vector3>(
+      new Vector3(),
+      new Vector3(),
+      new Vector3(),
+      new Vector3(),
+      new Vector3(),
+      new Vector3(),
+      new Vector3(),
+      new Vector3()
+    )
+  };
+
+  /**
+   * @deprecated usage of mutable static variables is unsafe
+   * @private
+   */
+  private static readonly _calculateCameraFarBuffers: CameraFarBuffers = {
+    nearPlaneCoplanarPoint: new Vector3(),
+    nearPlane: new Plane()
+  };
+
+  private readonly _instanceUpdateNearAndFarPlaneBuffers: NearAndFarPlaneBuffers = {
     cameraPosition: new Vector3(),
     cameraDirection: new Vector3(),
     corners: new Array<Vector3>(
@@ -28,10 +64,11 @@ export class CameraManagerHelper {
     )
   };
 
-  private static readonly _calculateCameraFarBuffers = {
+  private readonly _instanceCalculateCameraFarBuffers: CameraFarBuffers = {
     nearPlaneCoplanarPoint: new Vector3(),
     nearPlane: new Plane()
   };
+
   /**
    * Calculates camera target based on new camera rotation.
    * @param camera Used camera instance.
@@ -76,9 +113,53 @@ export class CameraManagerHelper {
    * Updates near and far plane of the camera based on the bounding box.
    * @param camera Used camera instance.
    * @param boundingBox Bounding box of all objects on the scene.
+   * @deprecated use instance method instead
    */
   static updateCameraNearAndFar(camera: PerspectiveCamera, boundingBox: Box3): void {
-    const { cameraPosition, cameraDirection, corners } = this._updateNearAndFarPlaneBuffers;
+    CameraManagerHelper.updateCameraNearAndFarInternal(
+      camera,
+      boundingBox,
+      CameraManagerHelper._updateNearAndFarPlaneBuffers,
+      CameraManagerHelper._calculateCameraFarBuffers
+    );
+  }
+
+  /**
+   * Updates near and far plane of the camera based on the bounding box.
+   * @param camera Used camera instance.
+   * @param boundingBox Bounding box of all objects on the scene.
+   */
+  public updateCameraNearAndFar(camera: PerspectiveCamera, boundingBox: Box3): void {
+    CameraManagerHelper.updateCameraNearAndFarInternal(
+      camera,
+      boundingBox,
+      this._instanceUpdateNearAndFarPlaneBuffers,
+      this._instanceCalculateCameraFarBuffers
+    );
+  }
+
+  /**
+   * Calculates camera position and target that allows to see the content of provided bounding box.
+   * @param camera Used camera instance.
+   * @param boundingBox Bounding box to be fitted.
+   * @param radiusFactor The ratio of the distance from camera to center of box and radius of the box.
+   * @returns
+   */
+  static calculateCameraStateToFitBoundingBox(
+    camera: PerspectiveCamera,
+    boundingBox: Box3,
+    radiusFactor: number = 2
+  ): { position: Vector3; target: Vector3 } {
+    return fitCameraToBoundingBox(camera, boundingBox, radiusFactor);
+  }
+
+  private static updateCameraNearAndFarInternal(
+    camera: PerspectiveCamera,
+    boundingBox: Box3,
+    nearAndFarPlaneBuffers: NearAndFarPlaneBuffers,
+    cameraFarBuffers: CameraFarBuffers
+  ): void {
+    const { cameraPosition, cameraDirection, corners } = nearAndFarPlaneBuffers;
     this.getBoundingBoxCorners(boundingBox, corners);
     camera.getWorldPosition(cameraPosition);
     camera.getWorldDirection(cameraDirection);
@@ -89,7 +170,7 @@ export class CameraManagerHelper {
 
     // 2. Compute the far distance to the distance from camera to furthest
     // corner of the bounding box that is "in front" of the near plane
-    const far = this.calculateCameraFar(near, cameraPosition, cameraDirection, corners);
+    const far = this.calculateCameraFar(near, cameraPosition, cameraDirection, corners, cameraFarBuffers);
 
     // 3. Handle when camera is inside the model by adjusting the near value
     if (boundingBox.containsPoint(cameraPosition)) {
@@ -101,28 +182,14 @@ export class CameraManagerHelper {
     camera.updateProjectionMatrix();
   }
 
-  /**
-   * Calculates camera position and target that allows to see the content of provided bounding box.
-   * @param camera Used camera instance.
-   * @param boundingBox Bounding box to be fitted.
-   * @param radiusFactor The ratio of the distance from camera to center of box and radius of the box.
-   * @returns
-   */
-  static calculateCameraStateToFitBoundingBox(
-    camera: PerspectiveCamera,
-    boundingBox: Box3,
-    radiusFactor: number = 2
-  ): { position: Vector3; target: Vector3 } {
-    return fitCameraToBoundingBox(camera, boundingBox, radiusFactor);
-  }
-
   private static calculateCameraFar(
     near: number,
     cameraPosition: Vector3,
     cameraDirection: Vector3,
-    corners: Array<Vector3>
+    corners: Array<Vector3>,
+    cameraFarBuffers: CameraFarBuffers
   ): number {
-    const { nearPlane, nearPlaneCoplanarPoint } = this._calculateCameraFarBuffers;
+    const { nearPlane, nearPlaneCoplanarPoint } = cameraFarBuffers;
 
     nearPlaneCoplanarPoint.copy(cameraPosition).addScaledVector(cameraDirection, near);
     nearPlane.setFromNormalAndCoplanarPoint(cameraDirection, nearPlaneCoplanarPoint);

viewer/packages/camera-manager/src/DefaultCameraManager.ts

@@ -56,6 +56,8 @@ export class DefaultCameraManager implements CameraManager {
   private _isDisposed = false;
   private _nearAndFarNeedsUpdate = false;
 
+  private readonly cameraManagerHelper = new CameraManagerHelper();
+
   // The active/inactive state of this manager. Does not always match up with the controls
   // as these are temporarily disabled to block onWheel input during `zoomToCursor`-mode
   private _isEnabled = true;
@@ -427,7 +429,7 @@ export class DefaultCameraManager implements CameraManager {
       return;
     }
     if (this.automaticNearFarPlane) {
-      CameraManagerHelper.updateCameraNearAndFar(camera, boundingBox);
+      this.cameraManagerHelper.updateCameraNearAndFar(camera, boundingBox);
     }
     if (this.automaticControlsSensitivity) {
       const diagonal = boundingBox.min.distanceTo(boundingBox.max);

viewer/packages/camera-manager/src/Flexible/FlexibleCameraManager.ts

@@ -50,6 +50,8 @@ export class FlexibleCameraManager extends PointerEvents implements IFlexibleCam
   private readonly _raycastCallback: RaycastCallback;
   private readonly _haveEventListeners: boolean;
 
+  private readonly cameraManagerHelper = new CameraManagerHelper();
+
   //================================================
   // CONSTRUCTOR
   //================================================
@@ -470,7 +472,7 @@ export class FlexibleCameraManager extends PointerEvents implements IFlexibleCam
     if (!this.options.automaticNearFarPlane) {
       return;
     }
-    CameraManagerHelper.updateCameraNearAndFar(this.camera, boundingBox);
+    this.cameraManagerHelper.updateCameraNearAndFar(this.camera, boundingBox);
   }
 
   private updateControlsSensitivity(boundingBox: Box3): void {

viewer/packages/camera-manager/src/StationaryCameraManager.ts

@@ -29,6 +29,7 @@ export class StationaryCameraManager implements CameraManager {
   private readonly _stopEventTrigger: DebouncedCameraStopEventTrigger;
   private _isDragging = false;
   private _pointerEventCache: Array<PointerEvent> = [];
+  private readonly cameraManagerHelper = new CameraManagerHelper();
 
   constructor(domElement: HTMLElement, camera: PerspectiveCamera) {
     this._domElement = domElement;
@@ -156,7 +157,7 @@ export class StationaryCameraManager implements CameraManager {
   }
 
   update(_: number, boundingBox: Box3): void {
-    CameraManagerHelper.updateCameraNearAndFar(this._camera, boundingBox);
+    this.cameraManagerHelper.updateCameraNearAndFar(this._camera, boundingBox);
   }
 
   dispose(): void {

viewer/reveal.api.md

@@ -333,7 +333,9 @@ export class CameraManagerHelper {
     };
     static calculateNewRotationFromTarget(camera: PerspectiveCamera, newTarget: Vector3): Quaternion;
     static calculateNewTargetFromRotation(camera: PerspectiveCamera, rotation: Quaternion, currentTarget: Vector3, position: Vector3): Vector3;
+    // @deprecated
     static updateCameraNearAndFar(camera: PerspectiveCamera, boundingBox: Box3): void;
+    updateCameraNearAndFar(camera: PerspectiveCamera, boundingBox: Box3): void;
 }
 
 // @public (undocumented)