Height query API for Unity

.github/workflows/build.yml

@@ -136,6 +136,8 @@ jobs:
           name: Windows Package
           path: d:\cesium\CesiumForUnityBuildProject\*.tgz
       - name: Run Tests
+        env:
+          CESIUM_ION_TOKEN_FOR_TESTS: ${{ secrets.CESIUM_ION_TOKEN_FOR_TESTS }}
         run: |
           start -FilePath "C:\Program Files\Unity\Hub\Editor\2022.3.41f1\Editor\Unity.exe" -ArgumentList "-runTests -batchmode -projectPath d:\cesium\CesiumForUnityBuildProject -testResults d:\cesium\temp\TestResults.xml -testPlatform PlayMode -logFile d:\cesium\temp\test-log.txt" -Wait
           cat d:\cesium\temp\test-log.txt
@@ -271,6 +273,8 @@ jobs:
           name: macOS Package
           path: ~/cesium/CesiumForUnityBuildProject/*.tgz
       - name: Run Tests
+        env:
+          CESIUM_ION_TOKEN_FOR_TESTS: ${{ secrets.CESIUM_ION_TOKEN_FOR_TESTS }}
         run: |
           /Applications/Unity/Hub/Editor/2022.3.41f1/Unity.app/Contents/MacOS/Unity -runTests -batchmode -projectPath ~/cesium/CesiumForUnityBuildProject -testResults ~/cesium/CesiumForUnityBuildProject/TestResults.xml -testPlatform PlayMode -logFile ~/cesium/CesiumForUnityBuildProject/test-log.txt
           cat ~/cesium/CesiumForUnityBuildProject/test-log.txt

CHANGES.md

@@ -5,6 +5,7 @@
 ##### Additions :tada:
 
 - Added a new `CesiumCameraManager` component. It allows configuration of the cameras to use for Cesium3DTileset culling and level-of-detail.
+- Added `SampleHeightMostDetailed` method to `Cesium3DTileset`. It asynchronously queries the height of a tileset at a list of positions.
 
 ##### Fixes :wrench:
 

Reinterop~/CSharpObjectHandleUtility.cs

@@ -46,7 +46,19 @@ public static void FreeHandle(IntPtr handle)
                         if (handle == IntPtr.Zero)
                             return;
 
-                        GCHandle.FromIntPtr(handle).Free();
+                        try
+                        {
+                            GCHandle.FromIntPtr(handle).Free();
+                        }
+                        catch (ArgumentException e)
+                        {
+                            // The "GCHandle value belongs to a different domain" exception tends
+                            // to happen on AppDomain reload, which is common in Unity.
+                            // Catch the exception to prevent it propagating through our native
+                            // code and blowing things up.
+                            // See: https://github.com/CesiumGS/cesium-unity/issues/18
+                            System.Console.WriteLine(e.ToString());
+                        }
                     }
 
                     public static object GetObjectFromHandle(IntPtr handle)

Reinterop~/MethodsImplementedInCpp.cs

@@ -344,7 +344,7 @@ private static void GenerateMethod(CppGenerationContext context, TypeToGenerate
 
             CSharpType csWrapperType = CSharpType.FromSymbol(context, item.Type);
             CSharpType csReturnType = CSharpType.FromSymbol(context, method.ReturnType);
-            var csParameters = method.Parameters.Select(parameter => (Name: parameter.Name, CallName: parameter.Name, Type: CSharpType.FromSymbol(context, parameter.Type)));
+            var csParameters = method.Parameters.Select(parameter => (Name: parameter.Name, CallName: parameter.Name, Type: CSharpType.FromSymbol(context, parameter.Type), IsParams: parameter.IsParams));
             var csParametersInterop = csParameters;
             var implementationPointer = new CSharpType(context, InteropTypeKind.Primitive, csWrapperType.Namespaces, csWrapperType.Name + ".ImplementationHandle", csWrapperType.SpecialType, null);
 
@@ -354,13 +354,13 @@ private static void GenerateMethod(CppGenerationContext context, TypeToGenerate
                 {
                     csParametersInterop = new[]
                     {
-                        (Name: "implementation", CallName: "_implementation", Type: implementationPointer)
+                        (Name: "implementation", CallName: "_implementation", Type: implementationPointer, IsParams: false)
                     }.Concat(csParametersInterop);
                 }
 
                 csParametersInterop = new[]
                 {
-                    (Name: "thiz", CallName: "this", Type: csWrapperType),
+                    (Name: "thiz", CallName: "this", Type: csWrapperType, IsParams: false),
                 }.Concat(csParametersInterop);
             }
 
@@ -370,7 +370,7 @@ private static void GenerateMethod(CppGenerationContext context, TypeToGenerate
             {
                 csParametersInterop = csParametersInterop.Concat(new[]
                 {
-                    (Name: "pReturnValue", CallName: "&returnValue", Type: csInteropReturnType.AsPointer())
+                    (Name : "pReturnValue", CallName : "&returnValue", Type : csInteropReturnType.AsPointer(), IsParams : false)
                 });
                 csInteropReturnType = CSharpType.FromSymbol(context, returnType.Kind == InteropTypeKind.Nullable ? context.Compilation.GetSpecialType(SpecialType.System_Byte) : context.Compilation.GetSpecialType(SpecialType.System_Void));
             }
@@ -429,7 +429,7 @@ private static void GenerateMethod(CppGenerationContext context, TypeToGenerate
             result.CSharpPartialMethodDefinitions.Methods.Add(new(
                 methodDefinition:
                     $$"""
-                    {{modifiers}} partial {{csReturnType.GetFullyQualifiedName()}} {{method.Name}}({{string.Join(", ", csParameters.Select(parameter => $"{parameter.Type.GetFullyQualifiedName()} {parameter.Name}"))}})
+                    {{modifiers}} partial {{csReturnType.GetFullyQualifiedName()}} {{method.Name}}({{string.Join(", ", csParameters.Select(parameter => $"{(parameter.IsParams ? "params " : "")}{parameter.Type.GetFullyQualifiedName()} {parameter.Name}"))}})
                     {
                         unsafe
                         {

Runtime/Cesium3DTileset.cs

@@ -1,5 +1,9 @@
 using Reinterop;
 using System;
+using System.Collections;
+using System.Collections.Generic;
+using System.Threading.Tasks;
+using Unity.Mathematics;
 using UnityEngine;
 
 namespace CesiumForUnity
@@ -714,6 +718,30 @@ public bool createPhysicsMeshes
         /// </summary>
         public partial void FocusTileset();
 
+        /// <summary>
+        /// Initiates an asynchronous query for the height of this tileset at a list of 
+        /// cartographic positions, where the longitude (X) and latitude (Y) are given in degrees.
+        /// The most detailed available tiles are used to determine each height.
+        /// </summary>
+        /// <remarks>
+        /// <para>
+        /// The height of the input positions is ignored, unless height sampling fails
+        /// at that location. The output height is expressed in meters above the ellipsoid 
+        /// (usually WGS84), which should not be confused with a height above mean sea level.
+        /// </para>
+        /// <para>
+        /// Use <see cref="WaitForTask"/> inside a coroutine to wait for the asynchronous height
+        /// query to complete.
+        /// </para>
+        /// </remarks>
+        /// <param name="longitudeLatitudeHeightPositions">
+        /// The cartographic positions for which to sample heights. The X component is the 
+        /// Longitude (degrees), the Y component is the Latitude (degrees), and the Z component
+        /// is the Height (meters).
+        /// </param>
+        /// <returns>An asynchronous task that will provide the requested heights when complete.</returns>
+        public partial Task<CesiumSampleHeightResult> SampleHeightMostDetailed(params double3[] longitudeLatitudeHeightPositions);
+
         #endregion
 
         #region Private Methods
@@ -731,6 +759,8 @@ public bool createPhysicsMeshes
 
         #endregion
 
+        #region Backward Compatibility
+
         void ISerializationCallbackReceiver.OnBeforeSerialize()
         {
         }
@@ -748,5 +778,6 @@ void ISerializationCallbackReceiver.OnAfterDeserialize()
 #if UNITY_EDITOR
         private bool _useDefaultServer = false;
 #endif
+        #endregion
     }
 }

Runtime/CesiumSampleHeightResult.cs

@@ -0,0 +1,47 @@
+using Unity.Mathematics;
+
+namespace CesiumForUnity
+{
+    /// <summary>
+    /// The asynchronous result of a call to <see cref="Cesium3DTileset.SampleHeightMostDetailed"/>.
+    /// </summary>
+    public class CesiumSampleHeightResult
+    {
+        /// <summary>
+        /// The positions and their sampled heights. The X component is Longitude (degrees),
+        /// the Y component is Latitude (degrees), and the Z component is Height (meters) 
+        /// above the ellipsoid (usually WGS84).
+        /// </summary>
+        /// <remarks>
+        /// <para>
+        /// For each resulting position, its longitude and latitude values will match
+        /// values from its input. Its height will either be the height sampled from
+        /// the tileset at that position, or the original input height if the sample
+        /// was unsuccessful. To determine which, look at the value of
+        /// <see cref="CesiumSampleHeightResult.sampleSuccess"/> at the same index.
+        /// </para>
+        /// <para>
+        /// The returned height is measured from the ellipsoid (usually WGS84) and
+        /// should not be confused with a height above Mean Sea Level.
+        /// </para>
+        /// </remarks>
+        public double3[] longitudeLatitudeHeightPositions { get; set; }
+
+        /// <summary>
+        /// Indicates whether the height for the position at the corresponding index was sampled
+        /// successfully.
+        /// </summary>
+        /// <remarks>
+        /// If true, then the corresponding position in
+        /// <see cref="CesiumSampleHeightResult.longitudeLatitudeHeightPositions"/> uses
+        /// the height sampled from the tileset. If false, the height could not be sampled for 
+        /// the position, so its height is the same as the original input height.
+        /// </remarks>
+        public bool[] sampleSuccess { get; set; }
+
+        /// <summary>
+        /// Any warnings that occurred while sampling heights.
+        /// </summary>
+        public string[] warnings { get; set; }
+    }
+}

Runtime/ConfigureReinterop.cs

@@ -890,6 +890,21 @@ Cesium3DTilesetLoadFailureDetails tilesetDetails
                 camera = manager.additionalCameras[i];
             }
 
+            TaskCompletionSource<CesiumSampleHeightResult> promise = new TaskCompletionSource<CesiumSampleHeightResult>();
+            promise.SetException(new Exception("message"));
+            CesiumSampleHeightResult result = new CesiumSampleHeightResult();
+            result.longitudeLatitudeHeightPositions = null;
+            result.sampleSuccess = null;
+            result.warnings = null;
+            promise.SetResult(result);
+            Task<CesiumSampleHeightResult> task = promise.Task;
+
+            double3[] positions = null;
+            for (int i = 0; i < positions.Length; ++i)
+            {
+                positions[i] = positions[i];
+            }
+
 #if UNITY_EDITOR
             SceneView sv = SceneView.lastActiveSceneView;
             sv.pivot = sv.pivot;

Runtime/WaitForTask.cs

@@ -0,0 +1,25 @@
+using System;
+using UnityEngine;
+
+namespace CesiumForUnity
+{
+    /// <summary>
+    /// A YieldInstruction that can be yielded from a coroutine in order to wait
+    /// until a given task completes.
+    /// </summary>
+    public class WaitForTask : CustomYieldInstruction
+    {
+        private IAsyncResult _task;
+
+        /// <summary>
+        /// Initializes a new instance.
+        /// </summary>
+        /// <param name="task">The task to wait for.</param>
+        public WaitForTask(IAsyncResult task)
+        {
+            this._task = task;
+        }
+
+        public override bool keepWaiting => !this._task.IsCompleted;
+    }
+}

Tests/TestCesium3DTileset.cs

@@ -0,0 +1,129 @@
+using CesiumForUnity;
+using NUnit.Framework;
+using System;
+using System.Collections;
+using System.Threading.Tasks;
+using Unity.Mathematics;
+using UnityEngine;
+using UnityEngine.TestTools;
+
+public class TestCesium3DTileset
+{
+    [UnityTest]
+    public IEnumerator SampleHeightMostDetailedWorksWithAnEmptyArrayOfPositions()
+    {
+        GameObject go = new GameObject();
+        go.name = "Cesium World Terrain";
+        Cesium3DTileset tileset = go.AddComponent<Cesium3DTileset>();
+        tileset.ionAccessToken = Environment.GetEnvironmentVariable("CESIUM_ION_TOKEN_FOR_TESTS") ?? "";
+        tileset.ionAssetID = 1;
+
+        Task<CesiumSampleHeightResult> task = tileset.SampleHeightMostDetailed();
+
+        yield return new WaitForTask(task);
+
+        CesiumSampleHeightResult result = task.Result;
+        Assert.IsNotNull(result);
+        Assert.IsNotNull(result.longitudeLatitudeHeightPositions);
+        Assert.IsNotNull(result.sampleSuccess);
+        Assert.IsNotNull(result.warnings);
+        Assert.AreEqual(result.longitudeLatitudeHeightPositions.Length, 0);
+        Assert.AreEqual(result.sampleSuccess.Length, 0);
+        Assert.AreEqual(result.warnings.Length, 0);
+    }
+
+    [UnityTest]
+    public IEnumerator SampleHeightMostDetailedWorksWithASinglePosition()
+    {
+        GameObject go = new GameObject();
+        go.name = "Cesium World Terrain";
+        Cesium3DTileset tileset = go.AddComponent<Cesium3DTileset>();
+        tileset.ionAccessToken = Environment.GetEnvironmentVariable("CESIUM_ION_TOKEN_FOR_TESTS") ?? "";
+        tileset.ionAssetID = 1;
+
+        Task<CesiumSampleHeightResult> task = tileset.SampleHeightMostDetailed(new double3(-105.1, 40.1, 1.0));
+
+        yield return new WaitForTask(task);
+
+        CesiumSampleHeightResult result = task.Result;
+        Assert.IsNotNull(result);
+        Assert.IsNotNull(result.longitudeLatitudeHeightPositions);
+        Assert.IsNotNull(result.sampleSuccess);
+        Assert.IsNotNull(result.warnings);
+        Assert.AreEqual(result.longitudeLatitudeHeightPositions.Length, 1);
+        Assert.AreEqual(result.sampleSuccess.Length, 1);
+        Assert.AreEqual(result.warnings.Length, 0);
+
+        Assert.AreEqual(result.sampleSuccess[0], true);
+        Assert.AreEqual(result.longitudeLatitudeHeightPositions[0].x, -105.1, 1e-12);
+        Assert.AreEqual(result.longitudeLatitudeHeightPositions[0].y, 40.1, 1e-12);
+        // Returned height should be different from the original height (1.0) by at least one meter.
+        Assert.IsTrue(math.abs(result.longitudeLatitudeHeightPositions[0].z - 1.0) > 1.0);
+    }
+
+    [UnityTest]
+    public IEnumerator SampleHeightMostDetailedWorksWithMultiplePositions()
+    {
+        GameObject go = new GameObject();
+        go.name = "Cesium World Terrain";
+        Cesium3DTileset tileset = go.AddComponent<Cesium3DTileset>();
+        tileset.ionAccessToken = Environment.GetEnvironmentVariable("CESIUM_ION_TOKEN_FOR_TESTS") ?? "";
+        tileset.ionAssetID = 1;
+
+        Task<CesiumSampleHeightResult> task = tileset.SampleHeightMostDetailed(
+            new double3(-105.1, 40.1, 1.0),
+            new double3(105.1, -40.1, 1.0));
+
+        yield return new WaitForTask(task);
+
+        CesiumSampleHeightResult result = task.Result;
+        Assert.IsNotNull(result);
+        Assert.IsNotNull(result.longitudeLatitudeHeightPositions);
+        Assert.IsNotNull(result.sampleSuccess);
+        Assert.IsNotNull(result.warnings);
+        Assert.AreEqual(result.longitudeLatitudeHeightPositions.Length, 2);
+        Assert.AreEqual(result.sampleSuccess.Length, 2);
+        Assert.AreEqual(result.warnings.Length, 0);
+
+        Assert.AreEqual(result.sampleSuccess[0], true);
+        Assert.AreEqual(result.longitudeLatitudeHeightPositions[0].x, -105.1, 1e-12);
+        Assert.AreEqual(result.longitudeLatitudeHeightPositions[0].y, 40.1, 1e-12);
+        // Returned height should be different from the original height (1.0) by at least one meter.
+        Assert.IsTrue(math.abs(result.longitudeLatitudeHeightPositions[0].z - 1.0) > 1.0);
+
+        Assert.AreEqual(result.sampleSuccess[1], true);
+        Assert.AreEqual(result.longitudeLatitudeHeightPositions[1].x, 105.1, 1e-12);
+        Assert.AreEqual(result.longitudeLatitudeHeightPositions[1].y, -40.1, 1e-12);
+        // Returned height should be different from the original height (1.0) by at least one meter.
+        Assert.IsTrue(math.abs(result.longitudeLatitudeHeightPositions[1].z - 1.0) > 1.0);
+    }
+
+    [UnityTest]
+    public IEnumerator SampleHeightMostDetailedIndicatesNotSampledForPositionOutsideTileset()
+    {
+        GameObject go = new GameObject();
+        go.name = "Melbourne Photogrammetry";
+        Cesium3DTileset tileset = go.AddComponent<Cesium3DTileset>();
+        tileset.ionAccessToken = Environment.GetEnvironmentVariable("CESIUM_ION_TOKEN_FOR_TESTS") ?? "";
+        tileset.ionAssetID = 69380;
+
+        // Somewhere in Sydney, not Melbourne
+        Task<CesiumSampleHeightResult> task = tileset.SampleHeightMostDetailed(new double3(151.20972, -33.87100, 1.0));
+
+        yield return new WaitForTask(task);
+
+        CesiumSampleHeightResult result = task.Result;
+        Assert.IsNotNull(result);
+        Assert.IsNotNull(result.longitudeLatitudeHeightPositions);
+        Assert.IsNotNull(result.sampleSuccess);
+        Assert.IsNotNull(result.warnings);
+        Assert.AreEqual(result.longitudeLatitudeHeightPositions.Length, 1);
+        Assert.AreEqual(result.sampleSuccess.Length, 1);
+        Assert.AreEqual(result.warnings.Length, 0);
+
+        Assert.AreEqual(result.sampleSuccess[0], false);
+        Assert.AreEqual(result.longitudeLatitudeHeightPositions[0].x, 151.20972, 1e-12);
+        Assert.AreEqual(result.longitudeLatitudeHeightPositions[0].y, -33.87100, 1e-12);
+        Assert.AreEqual(result.longitudeLatitudeHeightPositions[0].z, 1.0, 1e-12);
+    }
+}