Update based on review

Runtime/CesiumOriginShift.cs

@@ -29,20 +29,6 @@ namespace CesiumForUnity
     [IconAttribute("Packages/com.cesium.unity/Editor/Resources/Cesium-24x24.png")]
     public class CesiumOriginShift : MonoBehaviour
     {
-        /// <summary>
-        /// When false, the origin will be shifted every frame.
-        /// When true, <see cref="activationDistance"/> will be used to specify the distance from the old
-        /// origin after which the origin will be shifted.
-        /// </summary>
-        public bool useActivationDistance
-        {
-            get => _useActivationDistance;
-            set => _useActivationDistance = value;
-        }
-
-        [SerializeField]
-        private bool _useActivationDistance = false;
-
         /// <summary>
         /// Specifies the minimum distance in meters from the old origin to the current origin before the 
         /// origin of the parent <see cref="CesiumGeoreference"/> will be shifted.
@@ -54,7 +40,7 @@ public double activationDistance
         }
 
         [SerializeField]
-        private double _activationDistance = 1.0;
+        private double _activationDistance = 0.0;
 
         void LateUpdate()
         {
@@ -69,15 +55,13 @@ void LateUpdate()
                 return;
             }
 
-            this.UpdateFromEcef(georeference, anchor);
+            this.UpdateFromEcef(georeference, anchor.positionGlobeFixed);
         }
 
         private List<CesiumSubScene> _sublevelsScratch = new List<CesiumSubScene>();
 
-        private void UpdateFromEcef(CesiumGeoreference georeference, CesiumGlobeAnchor anchor)
+        private void UpdateFromEcef(CesiumGeoreference georeference, double3 ecef)
         {
-            double3 ecef = anchor.positionGlobeFixed;
-
             CesiumSubScene closestLevel = null;
             double distanceSquaredToClosest = double.MaxValue;
 
@@ -128,9 +112,9 @@ private void UpdateFromEcef(CesiumGeoreference georeference, CesiumGlobeAnchor a
 
                 double distance = math.length(new double3(georeference.ecefX, georeference.ecefY, georeference.ecefZ) - ecef);
 
-                if (!this.useActivationDistance || distance >= this._activationDistance)
+                if (distance >= this._activationDistance)
                 {
-                    // Update the origin continuously.
+                    // Update the origin if we've surpassed the distance threshold.
                     georeference.SetOriginEarthCenteredEarthFixed(ecef.x, ecef.y, ecef.z);
                     // Make sure the physics system is informed that things have moved
                     Physics.SyncTransforms();

Tests/Comparers.cs

@@ -5,26 +5,45 @@ internal class Comparers
 {
     private class DoubleComparer : IEqualityComparer<double>
     {
-        private readonly double _epsilon;
+        private readonly double _absoluteEpsilon;
+        private readonly double _relativeEpsilon;
 
-        public DoubleComparer(double epsilon)
+        public DoubleComparer(double absoluteEpsilon)
         {
-            this._epsilon = epsilon;
+            this._absoluteEpsilon = absoluteEpsilon;
+            this._relativeEpsilon = 0.0;
+        }
+
+        public DoubleComparer(double absoluteEpsilon, double relativeEpsilon) : this(absoluteEpsilon)
+        {
+            this._relativeEpsilon = relativeEpsilon;
         }
 
         public bool Equals(double x, double y)
         {
-            return Math.Abs(x - y) <= this._epsilon;
+            double diff = Math.Abs(x - y);
+            return diff <= this._absoluteEpsilon ||
+                diff <= RelativeToAbsoluteEpsilon(x, y, this._relativeEpsilon);
         }
 
         public int GetHashCode(double obj)
         {
             throw new NotImplementedException();
         }
+
+        private double RelativeToAbsoluteEpsilon(double left, double right, double relativeEpsilon)
+        {
+            return relativeEpsilon * Math.Max(Math.Abs(left), Math.Abs(right));
+        }
     }
 
     public static IEqualityComparer<double> Double(double absoluteEpsilon)
     {
         return new DoubleComparer(absoluteEpsilon);
     }
+
+    public static IEqualityComparer<double> Double(double absoluteEpsilon, double relativeEpsilon)
+    {
+        return new DoubleComparer(absoluteEpsilon, relativeEpsilon);
+    }
 }

Tests/TestCesiumOriginShift.cs

@@ -1,6 +1,7 @@
 using CesiumForUnity;
 using NUnit.Framework;
 using System.Collections;
+using System.Collections.Generic;
 using Unity.Mathematics;
 using UnityEngine;
 using UnityEngine.TestTools;
@@ -114,7 +115,6 @@ public IEnumerator UsesActivationDistanceProperty()
         CesiumGlobeAnchor globeAnchor = goOriginShift.AddComponent<CesiumGlobeAnchor>();
 
         CesiumOriginShift originShift = goOriginShift.AddComponent<CesiumOriginShift>();
-        originShift.useActivationDistance = true;
         originShift.activationDistance = 5000;
 
         yield return null;
@@ -123,19 +123,23 @@ public IEnumerator UsesActivationDistanceProperty()
 
         yield return null;
 
-        Assert.AreEqual(baseEcef.x + 4999.0, globeAnchor.positionGlobeFixed.x);
-        Assert.AreEqual(baseEcef.x + 0, georeference.ecefX);
+        IEqualityComparer<double> epsilon6 = Comparers.Double(1e-6);
+
+        // The anchor is still within the distance threshold, so the georeference should remain unchanged.
+        Assert.That(baseEcef.x + 4999.0, Is.EqualTo(globeAnchor.positionGlobeFixed.x).Using(epsilon6));
+        Assert.That(baseEcef.x, Is.EqualTo(georeference.ecefX).Using(epsilon6));
 
         globeAnchor.positionGlobeFixed = baseEcef + new double3(5010.0, 0, 0);
         yield return null;
 
-        Assert.AreEqual(baseEcef.x + 5010.0, globeAnchor.positionGlobeFixed.x);
-        Assert.AreEqual(baseEcef.x + 5010.0, georeference.ecefX);
+        // The anchor has surpassed the distance threshold, so the georeference should shift to the anchor's ECEF coordinates.
+        Assert.That(baseEcef.x + 5010.0, Is.EqualTo(globeAnchor.positionGlobeFixed.x).Using(epsilon6));
+        Assert.That(globeAnchor.positionGlobeFixed.x, Is.EqualTo(georeference.ecefX).Using(epsilon6));
     }
 
     // Testing a bug where the character controller would cause a jump ahead when the activation distance is hit.
     [UnityTest]
-    public IEnumerator ShiftingOriginWithCharacterController()
+    public IEnumerator ShiftsOriginWithCharacterController()
     {
         double3 baseEcef = new double3(-2694020, -4297355, 3854720);
 
@@ -150,7 +154,6 @@ public IEnumerator ShiftingOriginWithCharacterController()
         CesiumGlobeAnchor globeAnchor = goOriginShift.AddComponent<CesiumGlobeAnchor>();
 
         CesiumOriginShift originShift = goOriginShift.AddComponent<CesiumOriginShift>();
-        originShift.useActivationDistance = true;
         originShift.activationDistance = 5000;
 
         CharacterController controller = goOriginShift.AddComponent<CharacterController>();
@@ -161,7 +164,9 @@ public IEnumerator ShiftingOriginWithCharacterController()
 
         yield return new WaitForEndOfFrame();
 
-        Assert.AreEqual((float)baseEcef.x, (float)globeAnchor.positionGlobeFixed.x);
+        IEqualityComparer<double> epsilon6 = Comparers.Double(1e-6, 1e-6);
+
+        Assert.That(baseEcef.x, Is.EqualTo(globeAnchor.positionGlobeFixed.x).Using(epsilon6));
 
         // speed per second
         double speed = 1000.0;
@@ -182,11 +187,8 @@ public IEnumerator ShiftingOriginWithCharacterController()
             yield return new WaitForEndOfFrame();
 
             globeAnchor.Sync();
-            Assert.AreEqual((float)(previousPositionEcef.x + unitsEcef), (float)globeAnchor.positionGlobeFixed.x);
+            Assert.That(previousPositionEcef.x + unitsEcef, Is.EqualTo(globeAnchor.positionGlobeFixed.x).Using(epsilon6));
             Assert.Less(georeference.ecefX - globeAnchor.positionGlobeFixed.x, 5000.0);
-
-            Debug.Log($"georeference d: ({georeference.ecefX - baseEcef.x}, {georeference.ecefY - baseEcef.y}, {georeference.ecefZ - baseEcef.z})");
-            Debug.Log($"anchor d: {globeAnchor.positionGlobeFixed - baseEcef}");
         }
     }
 }