Vector Tiles: Support 3DTILES_content_gltf_vector and EXT_mesh_polygon

Apps/SampleData/vector/sample-cities-spain-v02.tileset.json

@@ -0,0 +1,20 @@
+{
+  "asset": { "version": "1.1" },
+  "extensionsUsed": [ "3DTILES_content_gltf", "3DTILES_content_gltf_vector" ],
+  "extensions": {
+    "3DTILES_content_gltf": {
+      "extensionsUsed": [ "EXT_mesh_features" ],
+      "extensionsRequired": [  ]
+    }
+  },
+  "geometricError": 2000000.0,
+  "root": {
+    "boundingVolume": { "region": [ -0.14912553056282754, 0.630603674286057, 0.038089971913258434, 0.7585433514898835, -1000, 1000 ] },
+    "geometricError": 0.0,
+    "refine": "REPLACE",
+    "content": {
+      "uri": "sample-cities-spain-v02.glb",
+      "extensions": { "3DTILES_content_gltf_vector": { "vector": true } }
+    }
+  }
+}

Apps/SampleData/vector/sample-us-outline-v02.tileset.json

@@ -0,0 +1,20 @@
+{
+  "asset": { "version": "1.1" },
+  "extensionsUsed": [ "3DTILES_content_gltf", "3DTILES_content_gltf_vector" ],
+  "extensions": {
+    "3DTILES_content_gltf": {
+      "extensionsUsed": [ "EXT_mesh_features", "KHR_mesh_primitive_restart" ],
+      "extensionsRequired": [ "KHR_mesh_primitive_restart" ]
+    }
+  },
+  "geometricError": 2000000.0,
+  "root": {
+    "boundingVolume": { "region": [ -3.1267109291897386, 0.31214887295348465, 3.13772622569785, 1.2453371191800977, -1000, 1000 ] },
+    "geometricError": 0.0,
+    "refine": "REPLACE",
+    "content": {
+      "uri": "sample-us-outline-v02.glb",
+      "extensions": { "3DTILES_content_gltf_vector": { "vector": true } }
+    }
+  }
+}

Apps/SampleData/vector/sample-us-states-v02.tileset.json

@@ -0,0 +1,20 @@
+{
+  "asset": { "version": "1.1" },
+  "extensionsUsed": [ "3DTILES_content_gltf", "3DTILES_content_gltf_vector" ],
+  "extensions": {
+    "3DTILES_content_gltf": {
+      "extensionsUsed": [ "EXT_mesh_features", "EXT_mesh_polygon" ],
+      "extensionsRequired": [  ]
+    }
+  },
+  "geometricError": 2000000.0,
+  "root": {
+    "boundingVolume": { "region": [ -3.1267109291897386, 0.31214887295348465, 3.13772622569785, 1.2453371191800977, -1000, 1000 ] },
+    "geometricError": 0.0,
+    "refine": "REPLACE",
+    "content": {
+      "uri": "sample-us-states-v02.glb",
+      "extensions": { "3DTILES_content_gltf_vector": { "vector": true } }
+    }
+  }
+}

packages/engine/Source/Scene/Cesium3DTileContentFactory.js

@@ -101,7 +101,11 @@ const Cesium3DTileContentFactory = {
       return GaussianSplat3DTileContent.fromGltf(tileset, tile, resource, glb);
     }
 
-    if (tileset.isGltfExtensionUsed("CESIUM_mesh_vector")) {
+    // @deprecated CESIUM_mesh_vector to be removed after v1.142 release.
+    if (
+      tileset.hasExtension("3DTILES_content_gltf_vector") ||
+      tileset.isGltfExtensionUsed("CESIUM_mesh_vector")
+    ) {
       return VectorGltf3DTileContent.fromGltf(tileset, tile, resource, glb);
     }
 
@@ -114,7 +118,11 @@ const Cesium3DTileContentFactory = {
       return GaussianSplat3DTileContent.fromGltf(tileset, tile, resource, json);
     }
 
-    if (tileset.isGltfExtensionUsed("CESIUM_mesh_vector")) {
+    // @deprecated CESIUM_mesh_vector to be removed after v1.142 release.
+    if (
+      tileset.hasExtension("3DTILES_content_gltf_vector") ||
+      tileset.isGltfExtensionUsed("CESIUM_mesh_vector")
+    ) {
       return VectorGltf3DTileContent.fromGltf(tileset, tile, resource, json);
     }
 

packages/engine/Source/Scene/Cesium3DTileset.js

@@ -3686,11 +3686,11 @@ Cesium3DTileset.supportedExtensions = {
   "3DTILES_metadata": true,
   "3DTILES_implicit_tiling": true,
   "3DTILES_content_gltf": true,
+  "3DTILES_content_gltf_vector": true,
   "3DTILES_multiple_contents": true,
   "3DTILES_bounding_volume_S2": true,
   "3DTILES_batch_table_hierarchy": true,
   "3DTILES_draco_point_compression": true,
-  CESIUM_mesh_vector: true,
   MAXAR_content_geojson: true,
 };
 

packages/engine/Source/Scene/GltfLoader.js

@@ -64,6 +64,7 @@ const {
   LineStyle,
   Material,
   Vector,
+  Polygon,
 } = ModelComponents;
 
 /**
@@ -899,6 +900,38 @@ function loadAccessor(loader, accessor, useQuaternion) {
   return loadDefaultAccessorValues(accessor, values);
 }
 
+function loadAccessorTypedArray(loader, accessor) {
+  const values = ComponentDatatype.createTypedArray(
+    accessor.componentType,
+    accessor.count * AttributeType.getNumberOfComponents(accessor.type),
+  );
+
+  if (!defined(accessor.bufferView)) {
+    return values;
+  }
+
+  const bufferViewLoader = getBufferViewLoader(loader, accessor.bufferView);
+
+  // Save a link to the gltfJson, which is removed after bufferViewLoader.load()
+  const { gltfJson } = loader;
+
+  const promise = bufferViewLoader.load().then(() => {
+    if (loader.isDestroyed()) {
+      return;
+    }
+    const result = getPackedTypedArray(
+      gltfJson,
+      accessor,
+      bufferViewLoader.typedArray,
+    );
+    values.set(result);
+  });
+
+  loader._loaderPromises.push(promise);
+
+  return values;
+}
+
 function fromArray(MathType, values) {
   if (!defined(values)) {
     return undefined;
@@ -2208,6 +2241,13 @@ function loadPrimitive(loader, gltfPrimitive, hasInstances, frameState) {
   }
 
   const extensions = gltfPrimitive.extensions ?? Frozen.EMPTY_OBJECT;
+
+  const polygonExtension = extensions.EXT_mesh_polygon;
+  if (defined(polygonExtension)) {
+    primitive.polygon = loadMeshPolygonExtension(loader, polygonExtension);
+  }
+
+  // @deprecated CESIUM_mesh_vector to be removed after v1.142 release.
   const meshVectorExtension = extensions.CESIUM_mesh_vector;
   if (defined(meshVectorExtension)) {
     primitive.vector = loadMeshVectorExtension(loader, meshVectorExtension);
@@ -2365,12 +2405,45 @@ function loadPrimitiveOutline(loader, outlineExtension) {
   return loadAccessor(loader, accessor, useQuaternion);
 }
 
+/**
+ * Load EXT_mesh_polygon.
+ * @param {GltfLoader} loader
+ * @param {*} polygonExtension
+ * @returns {ModelComponents.Polygon}
+ * @ignore
+ */
+function loadMeshPolygonExtension(loader, polygonExtension) {
+  const result = new Polygon();
+  const accessors = loader.gltfJson.accessors;
+
+  result.count = polygonExtension.count;
+
+  result.indicesOffsets = loadAccessorTypedArray(
+    loader,
+    accessors[polygonExtension.indicesOffsets],
+  );
+
+  if (defined(polygonExtension.triangleIndices)) {
+    result.triangleIndices = loadAccessorTypedArray(
+      loader,
+      accessors[polygonExtension.triangleIndices],
+    );
+    result.triangleIndicesOffsets = loadAccessorTypedArray(
+      loader,
+      accessors[polygonExtension.triangleIndicesOffsets],
+    );
+  }
+
+  return result;
+}
+
 /**
  * Load CESIUM_mesh_vector.
  * @param {GltfLoader} loader
  * @param {*} meshVectorExtension
  * @returns {ModelComponents.Vector}
  * @ignore
+ * @deprecated
  */
 function loadMeshVectorExtension(loader, meshVectorExtension) {
   if (!defined(meshVectorExtension)) {

packages/engine/Source/Scene/Model/ModelUtility.js

@@ -353,6 +353,7 @@ ModelUtility.supportedExtensions = {
   EXT_instance_features: true,
   EXT_mesh_features: true,
   EXT_mesh_gpu_instancing: true,
+  EXT_mesh_polygon: true,
   EXT_mesh_primitive_edge_visibility: true,
   EXT_meshopt_compression: true,
   EXT_primitive_voxels: true,
@@ -368,6 +369,7 @@ ModelUtility.supportedExtensions = {
   KHR_materials_clearcoat: true,
   KHR_materials_unlit: true,
   KHR_mesh_quantization: true,
+  KHR_mesh_primitive_restart: true,
   KHR_techniques_webgl: true,
   KHR_texture_basisu: true,
   KHR_texture_transform: true,