create test with gpu instancing and ext_instance_features

src/SharpGLTF.Cesium/Schema2/MeshExtInstanceFeatures.cs

@@ -29,7 +29,7 @@ namespace SharpGLTF.Schema2
 
         protected override void OnValidateContent(ValidationContext validate)
         {
-            var extInstanceFeatures = (MeshExtInstanceFeatures)_node.Extensions.FirstOrDefault();
+            var extInstanceFeatures = (MeshExtInstanceFeatures)_node.Extensions.Where(item => item is MeshExtInstanceFeatures).FirstOrDefault();
 
             validate.NotNull(nameof(FeatureIds), extInstanceFeatures.FeatureIds);
             validate.IsTrue(nameof(FeatureIds), extInstanceFeatures.FeatureIds.Count > 0, "Instance FeatureIds has items");
@@ -40,6 +40,10 @@ namespace SharpGLTF.Schema2
 
     public partial class MeshExtInstanceFeatureID
     {
+        public MeshExtInstanceFeatureID()
+        {
+        }
+
         public MeshExtInstanceFeatureID(int featureCount, int? attribute = null, int? propertyTable = null, string label = null, int? nullFeatureId = null)
         {
             _featureCount = featureCount;

tests/SharpGLTF.Cesium.Tests/ExtInstanceFeaturesTests.cs

@@ -1,13 +1,12 @@
 using NUnit.Framework;
-using SharpGLTF.Geometry;
-using SharpGLTF.Geometry.VertexTypes;
-using SharpGLTF.Materials;
 using SharpGLTF.Scenes;
 using SharpGLTF.Schema2;
+using SharpGLTF.Transforms;
 using SharpGLTF.Validation;
 using System.Collections.Generic;
 using System.Linq;
 using System.Numerics;
+using System.Text.Json.Nodes;
 
 namespace SharpGLTF.Cesium
 {
@@ -21,33 +20,35 @@ namespace SharpGLTF.Cesium
         }
 
         [Test(Description = "Creates a simple triangle with Cesium EXT_Instance_Features")]
-        public void AddExtInstanceFeatures()
+        public void AddExtGpuInstanceFeatures()
         {
-            TestContext.CurrentContext.AttachGltfValidatorLinks();
+            var settings = SceneBuilderSchema2Settings.WithGpuInstancing;
+            settings.GpuMeshInstancingMinCount = 0;
 
-            // todo: create a test with ext_mesh_gpu_instancing
+            var modelRoot = ModelRoot.Load(ResourceInfo.From("tree.glb"));
+            var meshBuilder = modelRoot.LogicalMeshes.First().ToMeshBuilder();
+            var sceneBuilder = new SceneBuilder();
+            var quaternion = Quaternion.CreateFromYawPitchRoll(0, 0, 0);
+            var scale = Vector3.One;
 
-            var material = MaterialBuilder.CreateDefault();
+            sceneBuilder.
+                    AddRigidMesh(meshBuilder, new AffineTransform(scale, quaternion, new Vector3(-10, 0, 10))).
+                    WithExtras(JsonNode.Parse("{\"_FEATURE_ID_0\":0}"));
+            sceneBuilder.
+                    AddRigidMesh(meshBuilder, new AffineTransform(scale, quaternion, new Vector3(0, 0, 0))).
+                    WithExtras(JsonNode.Parse("{\"_FEATURE_ID_0\":1}"));
 
-            var mesh = new MeshBuilder<VertexPosition>("mesh");
 
-            var prim = mesh.UsePrimitive(material);
-            prim.AddTriangle(new VertexPosition(-10, 0, 0), new VertexPosition(10, 0, 0), new VertexPosition(0, 10, 0));
-
-            var scene = new SceneBuilder();
-
-            scene.AddRigidMesh(mesh, Matrix4x4.Identity);
-
-            var model = scene.ToGltf2();
-
-            // following the sample at https://github.com/CesiumGS/glTF/tree/3d-tiles-next/extensions/2.0/Vendor/EXT_instance_features#feature-id-by-gpu-instance
-            var featureId0 = new MeshExtInstanceFeatureID(2, 0, 0, "Forests",2);
+            var featureId0 = new MeshExtInstanceFeatureID(2, 0, 0, "Forests", 2);
             var featureId1 = new MeshExtInstanceFeatureID(9, propertyTable: 1, label: "Trees");
 
             var featureIds = new List<MeshExtInstanceFeatureID>() { featureId0, featureId1 };
+
+            var model = sceneBuilder.ToGltf2(settings);
             model.LogicalNodes[0].SetFeatureIds(featureIds);
 
-            var cesiumExtInstanceFeaturesExtension = (MeshExtInstanceFeatures)model.LogicalNodes[0].Extensions.FirstOrDefault();
+            var cesiumExtInstanceFeaturesExtension = (MeshExtInstanceFeatures)model.LogicalNodes[0].Extensions.Where(item => item is MeshExtInstanceFeatures).FirstOrDefault();
+
             Assert.NotNull(cesiumExtInstanceFeaturesExtension.FeatureIds);
 
             Assert.IsTrue(cesiumExtInstanceFeaturesExtension.FeatureIds.Equals(featureIds));
@@ -57,9 +58,9 @@ namespace SharpGLTF.Cesium
             var ctx = new ValidationResult(model, ValidationMode.Strict, true);
             model.ValidateContent(ctx.GetContext());
 
-            scene.AttachToCurrentTest("cesium_ext_instance_features.glb");
-            scene.AttachToCurrentTest("cesium_ext_instance_features.gltf");
-            scene.AttachToCurrentTest("cesium_ext_instance_features.plotly");
+            model.AttachToCurrentTest("cesium_ext_instance_features.glb");
+            model.AttachToCurrentTest("cesium_ext_instance_features.gltf");
+            model.AttachToCurrentTest("cesium_ext_instance_features.plotly");
         }
     }
 }

tests/SharpGLTF.Cesium.Tests/SharpGLTF.Cesium.Tests.csproj

@@ -20,4 +20,10 @@
     <PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.8.0" />
   </ItemGroup>
 
+  <ItemGroup>
+    <None Update="tree.glb">
+      <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
+    </None>
+  </ItemGroup>
+
 </Project>