Add Component Cache

com.microsoft.mrtk.core/Utilities/ComponentCache.cs

@@ -0,0 +1,45 @@
+// Copyright (c) Microsoft Corporation.
+// Licensed under the MIT License.
+
+using UnityEngine;
+
+namespace Microsoft.MixedReality.Toolkit
+{
+    /// <summary>
+    /// A static helper class which caches instances of a component of type T.
+    /// This is called in place of calling FindFirstObjectByType and FindObjectsByType to improve performance.
+    /// </summary>
+    public static class ComponentCache<T> where T : Component
+    {
+        private static T cacheFirstInstance = null;
+
+        /// <summary>
+        /// Finds the first instance of an object of the given type. 
+        /// </summary>
+        /// <returns>
+        /// The first instance of an object of the given type. 
+        /// </returns>
+        public static T FindFirstActiveInstance()
+        {
+            _ = TryFindFirstActiveInstance(out T result);
+            return result;
+        }
+
+        /// <summary>
+        /// Finds the first instance of an object of the given type. 
+        /// </summary>
+        /// <returns>
+        /// True if an instance was found, and false otherwise. 
+        /// </returns>
+        public static bool TryFindFirstActiveInstance(out T result)
+        {
+            if (cacheFirstInstance == null || !cacheFirstInstance.gameObject.activeInHierarchy)
+            {
+                cacheFirstInstance = Object.FindFirstObjectByType<T>();
+            }
+
+            result = cacheFirstInstance;
+            return result != null;
+        }
+    }
+}

com.microsoft.mrtk.core/Utilities/ControllerLookup.cs

@@ -56,5 +56,12 @@ public XRBaseController RightHandController
             set => rightHandController = value;
         }
 
+        private void OnValidate()
+        {
+            if (FindObjectsByType<ControllerLookup>(FindObjectsSortMode.None).Length > 1)
+            {
+                Debug.LogWarning("Found more than one instance of the ControllerLookup class in the hierarchy. There should only be one");
+            }
+        }
     }
 }

com.microsoft.mrtk.input/InteractionModes/FlatScreenModeDetector.cs

@@ -22,20 +22,7 @@ internal class FlatScreenModeDetector : MonoBehaviour, IInteractionModeDetector
 
         public void Awake()
         {
-            ControllerLookup[] lookups = GameObject.FindObjectsOfType(typeof(ControllerLookup)) as ControllerLookup[];
-            if (lookups.Length == 0)
-            {
-                Debug.LogError("Could not locate an instance of the ControllerLookup class in the hierarchy. It is recommended to add ControllerLookup to your camera rig.");
-            }
-            else if (lookups.Length > 1)
-            {
-                Debug.LogWarning("Found more than one instance of the ControllerLookup class in the hierarchy. Defaulting to the first instance.");
-                controllerLookup = lookups[0];
-            }
-            else
-            {
-                controllerLookup = lookups[0];
-            }
+            controllerLookup = ComponentCache<ControllerLookup>.FindFirstActiveInstance();
         }
 
         /// <inheritdoc />

com.microsoft.mrtk.input/InteractionModes/InteractionModeManager.cs

@@ -188,7 +188,7 @@ internal protected XRInteractionManager InteractionManager
             {
                 if (interactionManager == null)
                 {
-                    interactionManager = FindObjectOfType<XRInteractionManager>();
+                    interactionManager = ComponentCache<XRInteractionManager>.FindFirstActiveInstance();
                 }
 
                 return interactionManager;

com.microsoft.mrtk.input/InteractionModes/ProximityDetector.cs

@@ -63,7 +63,7 @@ private void Awake()
         {
             if (interactionManager == null)
             {
-                interactionManager = FindObjectOfType<XRInteractionManager>();
+                interactionManager = ComponentCache<XRInteractionManager>.FindFirstActiveInstance();
             }
 
             if (interactionManager == null)

com.microsoft.mrtk.spatialmanipulation/Solvers/Solver.cs

@@ -244,25 +244,9 @@ protected virtual void Start()
         {
             // Find the controller lookup class in the hierarchy. Solvers that require access to the
             // left, right or gaze controllers will use the references stored in this class.
-            //
-            // While FindObjectsOfType can be an expensive method, the controllerLookup variable is
-            // static. The hierarchy traversal will occur a maximum of once per scene.
             if (controllerLookup == null)
             {
-                ControllerLookup[] lookups = GameObject.FindObjectsOfType(typeof(ControllerLookup)) as ControllerLookup[];
-                if (lookups.Length == 0)
-                {
-                    Debug.LogError("Could not locate an instance of the ControllerLookup class in the hierarchy. It is recommended to add ControllerLookup to your camera rig.");
-                }
-                else if (lookups.Length > 1)
-                {
-                    Debug.LogWarning("Found more than one instance of the ControllerLookup class in the hierarchy. Defaulting to the first instance.");
-                    controllerLookup = lookups[0];
-                }
-                else
-                {
-                    controllerLookup = lookups[0];
-                }
+                controllerLookup = ComponentCache<ControllerLookup>.FindFirstActiveInstance();
             }
         }
 

com.microsoft.mrtk.spatialmanipulation/Solvers/TapToPlace.cs

@@ -477,7 +477,7 @@ private void RegisterPlacementAction()
 
             if (interactionManager == null)
             {
-                interactionManager = FindObjectOfType<XRInteractionManager>();
+                interactionManager = ComponentCache<XRInteractionManager>.FindFirstActiveInstance();
                 if (interactionManager == null)
                 {
                     Debug.LogError("No interaction manager found in scene. Please add an interaction manager to the scene.");

com.microsoft.mrtk.uxcore/Interop/UGUIInputAdapter.cs

@@ -93,7 +93,7 @@ internal protected XRInteractionManager InteractionManager
                     else
                     {
                         // Otherwise, go find one.
-                        interactionManager = FindObjectOfType<XRInteractionManager>();
+                        interactionManager = ComponentCache<XRInteractionManager>.FindFirstActiveInstance();
                     }
                 }
 

com.microsoft.mrtk.uxcore/SeeItSayIt/SeeItSayItLabelEnabler.cs

@@ -3,6 +3,9 @@
 
 using TMPro;
 using UnityEngine;
+#if MRTK_INPUT_PRESENT && MRTK_SPEECH_PRESENT
+using Microsoft.MixedReality.Toolkit.Input;
+#endif
 
 namespace Microsoft.MixedReality.Toolkit.UX
 {
@@ -47,6 +50,12 @@ private void Start()
             {
                 // Check if input and speech packages are present
 #if MRTK_INPUT_PRESENT && MRTK_SPEECH_PRESENT
+                // If we can't find any active speech interactors, then do not enable the labels.
+                if (!ComponentCache<SpeechInteractor>.FindFirstActiveInstance())
+                {
+                    return;
+                }
+
                 SeeItSayItLabel.SetActive(true);
 
                 // Children must be disabled so that they are not initially visible 

com.microsoft.mrtk.uxcore/Tests/Runtime/SeeItSayItLabelEnablerTests.cs

@@ -2,8 +2,10 @@
 // Licensed under the MIT License.
 
 using System.Collections;
+using System.Text.RegularExpressions;
 using System.Threading.Tasks;
 using Microsoft.MixedReality.Toolkit.Core.Tests;
+using Microsoft.MixedReality.Toolkit.Input;
 using Microsoft.MixedReality.Toolkit.Input.Tests;
 using NUnit.Framework;
 using TMPro;
@@ -21,11 +23,19 @@ public class SeeItSayItLabelEnablerTests : BaseRuntimeInputTests
         [UnityTest]
         public IEnumerator TestEnableAndSetLabel()
         {
+#if MRTK_INPUT_PRESENT && MRTK_SPEECH_PRESENT
+            SpeechInteractor interactor = Object.FindAnyObjectByType<SpeechInteractor>(FindObjectsInactive.Include);
+            interactor.gameObject.SetActive(true);
+
             GameObject testButton = SetUpButton(true, Control.None);
             yield return null;
+            if (Application.isBatchMode)
+            {
+                LogAssert.Expect(LogType.Exception, new Regex("Speech recognition is not supported on this machine"));
+            }
 
             Transform label = testButton.transform.GetChild(0);
-#if MRTK_INPUT_PRESENT && MRTK_SPEECH_PRESENT
+
             Transform sublabel = label.transform.GetChild(0);
             Assert.IsTrue(label.gameObject.activeSelf, "Label is enabled");
             Assert.IsTrue(!sublabel.gameObject.activeSelf, "Child objects are disabled");
@@ -57,11 +67,18 @@ public IEnumerator TestVoiceCommandsUnavailable()
         [UnityTest]
         public IEnumerator TestPositionCanvasLabel()
         {
+#if MRTK_INPUT_PRESENT && MRTK_SPEECH_PRESENT
+            SpeechInteractor interactor = Object.FindAnyObjectByType<SpeechInteractor>(FindObjectsInactive.Include);
+            interactor.gameObject.SetActive(true);
+
             GameObject testButton = SetUpButton(true, Control.Canvas);
             yield return null;
+            if (Application.isBatchMode)
+            {
+                LogAssert.Expect(LogType.Exception, new Regex("Speech recognition is not supported on this machine"));
+            }
 
             Transform label = testButton.transform.GetChild(0);
-#if MRTK_INPUT_PRESENT && MRTK_SPEECH_PRESENT
             RectTransform sublabel = label.transform.GetChild(0) as RectTransform;
             Assert.AreEqual(sublabel.anchoredPosition3D, new Vector3(10, -30, -10), "Label is positioned correctly");
 #else
@@ -76,11 +93,18 @@ public IEnumerator TestPositionCanvasLabel()
         [UnityTest]
         public IEnumerator TestPositionNonCanvasLabel()
         {
+#if MRTK_INPUT_PRESENT && MRTK_SPEECH_PRESENT
+            SpeechInteractor interactor = Object.FindAnyObjectByType<SpeechInteractor>(FindObjectsInactive.Include);
+            interactor.gameObject.SetActive(true);
+
             GameObject testButton = SetUpButton(true, Control.NonCanvas);
             yield return null;
+            if (Application.isBatchMode)
+            {
+                LogAssert.Expect(LogType.Exception, new Regex("Speech recognition is not supported on this machine"));
+            }
 
             Transform label = testButton.transform.GetChild(0);
-#if MRTK_INPUT_PRESENT && MRTK_SPEECH_PRESENT
             Assert.AreEqual(label.transform.localPosition, new Vector3(10f, -.504f, -.004f), "Label is positioned correctly");
 #else
             Assert.IsTrue(!label.gameObject.activeSelf, "Did not enable label because voice commands unavailable.");