DataSourceDisplay stays ready once loaded

Author: jjspace

CHANGES.md

@@ -4,6 +4,10 @@
 
 #### @cesium/engine
 
+##### Breaking Changes :mega:
+
+- Changed behavior of `DataSourceDisplay.ready` to always stay `true` once it is initially set to `true`.
+
 ##### Fixes :wrench:
 
 - Fixed error when resetting `Cesium3DTileset.modelMatrix` to its initial value. [#12409](https://github.com/CesiumGS/cesium/pull/12409)

packages/engine/Source/DataSources/BoundingSphereState.js

@@ -3,7 +3,7 @@
  * @enum {number}
  * @private
  */
-const BoundingSphereState = {
+const BoundingSphereState = Object.freeze({
   /**
    * The BoundingSphere has been computed.
    * @type BoundingSphereState
@@ -22,5 +22,5 @@ const BoundingSphereState = {
    * @constant
    */
   FAILED: 2,
-};
-export default Object.freeze(BoundingSphereState);
+});
+export default BoundingSphereState;

packages/engine/Source/DataSources/DataSourceDisplay.js

@@ -330,7 +330,10 @@ DataSourceDisplay.prototype.update = function (time) {
   if (!this._ready && result) {
     this._scene.requestRender();
   }
-  this._ready = result;
+
+  // once the DataSourceDisplay is ready it should stay ready to prevent
+  // entities from breaking updates when they become "un-ready"
+  this._ready = this._ready || result;
 
   return result;
 };
@@ -386,7 +389,7 @@ DataSourceDisplay.prototype.getBoundingSphere = function (
   Check.defined("result", result);
   //>>includeEnd('debug');
 
-  if (!this._ready && !allowPartial) {
+  if (!this._ready) {
     return BoundingSphereState.PENDING;
   }
 

packages/engine/Source/Widget/CesiumWidget.js

@@ -1134,8 +1134,6 @@ CesiumWidget.prototype._updateCanAnimate = function (isUpdated) {
   this._clock.canAnimate = isUpdated;
 };
 
-const boundingSphereScratch = new BoundingSphere();
-
 /**
  * @private
  */
@@ -1152,11 +1150,11 @@ CesiumWidget.prototype._onTick = function (clock) {
     const trackedEntity = this._trackedEntity;
     const trackedState = this._dataSourceDisplay.getBoundingSphere(
       trackedEntity,
-      true,
-      boundingSphereScratch,
+      false,
+      entityView.boundingSphere,
     );
     if (trackedState === BoundingSphereState.DONE) {
-      entityView.update(time, boundingSphereScratch);
+      entityView.update(time, entityView.boundingSphere);
     }
   }
 };
@@ -1414,6 +1412,8 @@ CesiumWidget.prototype._postRender = function () {
   updateTrackedEntity(this);
 };
 
+const zoomTargetBoundingSphereScratch = new BoundingSphere();
+
 function updateZoomTarget(widget) {
   const target = widget._zoomTarget;
   if (!defined(target) || widget.scene.mode === SceneMode.MORPHING) {
@@ -1511,13 +1511,15 @@ function updateZoomTarget(widget) {
     const state = widget._dataSourceDisplay.getBoundingSphere(
       entities[i],
       false,
-      boundingSphereScratch,
+      zoomTargetBoundingSphereScratch,
     );
 
     if (state === BoundingSphereState.PENDING) {
       return;
     } else if (state !== BoundingSphereState.FAILED) {
-      boundingSpheres.push(BoundingSphere.clone(boundingSphereScratch));
+      boundingSpheres.push(
+        BoundingSphere.clone(zoomTargetBoundingSphereScratch),
+      );
     }
   }
 
@@ -1552,6 +1554,8 @@ function updateZoomTarget(widget) {
   }
 }
 
+const trackedEntityBoundingSphereScratch2 = new BoundingSphere();
+
 function updateTrackedEntity(widget) {
   if (!widget._needTrackedEntityUpdate) {
     return;
@@ -1577,7 +1581,7 @@ function updateTrackedEntity(widget) {
   const state = widget._dataSourceDisplay.getBoundingSphere(
     trackedEntity,
     false,
-    boundingSphereScratch,
+    trackedEntityBoundingSphereScratch2,
   );
   if (state === BoundingSphereState.PENDING) {
     return;
@@ -1599,7 +1603,9 @@ function updateTrackedEntity(widget) {
   }
 
   const bs =
-    state !== BoundingSphereState.FAILED ? boundingSphereScratch : undefined;
+    state !== BoundingSphereState.FAILED
+      ? trackedEntityBoundingSphereScratch2
+      : undefined;
   widget._entityView = new EntityView(trackedEntity, scene, scene.ellipsoid);
   widget._entityView.update(currentTime, bs);
   widget._needTrackedEntityUpdate = false;