Apply root tile scale to tileset geometric error

CHANGES.md

@@ -28,6 +28,7 @@
 - Fixed an edge case in `viewer.flyTo` when flying to a imagery layer with certain terrain providers. [#10937](https://github.com/CesiumGS/cesium/issues/10937)
 - Fixed a crash in terrain sampling if any points have an indefined position due to being outside the rectangle. [#10931](https://github.com/CesiumGS/cesium/pull/10931)
 - Fixed label background rendering. [#11040](https://github.com/CesiumGS/cesium/issues/11040)
+- Fixed a bug where scale was not being applied to the top-level tileset geometric error. [#11047](https://github.com/CesiumGS/cesium/pull/11047)
 
 ### 1.101 - 2023-01-02
 

packages/engine/Source/Scene/Cesium3DTile.js

@@ -146,7 +146,7 @@ function Cesium3DTile(tileset, baseResource, header, parent) {
 
   if (!defined(this._geometricError)) {
     this._geometricError = defined(parent)
-      ? parent.geometricError
+      ? parent._geometricError
       : tileset._geometricError;
     Cesium3DTile._deprecationWarning(
       "geometricErrorUndefined",
@@ -874,7 +874,7 @@ Cesium3DTile.prototype.getScreenSpaceError = function (
   const heightFraction = defaultValue(progressiveResolutionHeightFraction, 1.0);
   const parentGeometricError = defined(this.parent)
     ? this.parent.geometricError
-    : tileset._geometricError;
+    : tileset._scaledGeometricError;
   const geometricError = useParentGeometricError
     ? parentGeometricError
     : this.geometricError;
@@ -1791,6 +1791,12 @@ Cesium3DTile.prototype.updateGeometricErrorScale = function () {
   const scale = Matrix4.getScale(this.computedTransform, scratchScale);
   const uniformScale = Cartesian3.maximumComponent(scale);
   this.geometricError = this._geometricError * uniformScale;
+
+  if (!defined(this.parent)) {
+    // Update the tileset's geometric error
+    const tileset = this._tileset;
+    tileset._scaledGeometricError = tileset._geometricError * uniformScale;
+  }
 };
 
 function applyDebugSettings(tile, tileset, frameState, passOptions) {

packages/engine/Source/Scene/Cesium3DTileset.js

@@ -167,6 +167,7 @@ function Cesium3DTileset(options) {
   this._asset = undefined; // Metadata for the entire tileset
   this._properties = undefined; // Metadata for per-model/point/etc properties
   this._geometricError = undefined; // Geometric error when the tree is not rendered at all
+  this._scaledGeometricError = undefined; // Geometric error scaled by root tile scale
   this._extensionsUsed = undefined;
   this._extensions = undefined;
   this._modelUpAxis = undefined;
@@ -1007,6 +1008,11 @@ function Cesium3DTileset(options) {
         return;
       }
 
+      // Set these before loading the tileset since _geometricError
+      // and _scaledGeometricError get accessed during tile creation
+      that._geometricError = tilesetJson.geometricError;
+      that._scaledGeometricError = tilesetJson.geometricError;
+
       that._root = that.loadTileset(resource, tilesetJson);
 
       // Handle legacy gltfUpAxis option
@@ -1019,7 +1025,6 @@ function Cesium3DTileset(options) {
       const asset = tilesetJson.asset;
       that._asset = asset;
       that._properties = tilesetJson.properties;
-      that._geometricError = tilesetJson.geometricError;
       that._extensionsUsed = tilesetJson.extensionsUsed;
       that._extensions = tilesetJson.extensions;
       that._modelUpAxis = modelUpAxis;

packages/engine/Specs/Scene/Cesium3DTileSpec.js

@@ -123,6 +123,7 @@ describe(
       debugShowViewerRequestVolume: true,
       modelMatrix: Matrix4.IDENTITY,
       _geometricError: 2,
+      _scaledGeometricError: 2,
       _heatmap: new Cesium3DTilesetHeatmap(),
     };
 
@@ -672,6 +673,28 @@ describe(
       expect(tile2._priority).toBeGreaterThanOrEqual(foveatedDeferralPenalty);
       tile2._priorityDeferred = false;
     });
+
+    it("tile transform scales geometric error", function () {
+      const header = clone(tileWithContentBoundingSphere, true);
+      header.transform = Matrix4.pack(
+        Matrix4.fromUniformScale(2.0),
+        new Array(16)
+      );
+
+      const mockTilesetScaled = clone(mockTileset, true);
+
+      const tile = new Cesium3DTile(
+        mockTilesetScaled,
+        "/some_url",
+        header,
+        undefined
+      );
+
+      expect(tile._geometricError).toBe(1);
+      expect(tile.geometricError).toBe(2);
+      expect(mockTilesetScaled._geometricError).toBe(2);
+      expect(mockTilesetScaled._scaledGeometricError).toBe(4);
+    });
   },
   "WebGL"
 );