Some minor reworks to use TryGetComponent in every-frame pointer code (#10315)

* Some minor reworks to use TryGetComponent in hot loops

* Update to use TryGetComponent

Author: keveleigh

Assets/MRTK/SDK/Features/UX/Scripts/Cursors/BaseCursor.cs

@@ -671,8 +671,12 @@ public virtual CursorContextEnum CheckCursorContext()
                 Transform contextCenter = null;
                 if (TargetedObject)
                 {
+#if UNITY_2019_4_OR_NEWER
+                    if (TargetedObject.TryGetComponent(out CursorContextInfo contextInfo) && contextInfo != null)
+#else
                     var contextInfo = TargetedObject.GetComponent<CursorContextInfo>();
                     if (contextInfo != null)
+#endif
                     {
                         cursorAction = contextInfo.CurrentCursorAction;
                         contextCenter = contextInfo.ObjectCenter;

Assets/MRTK/SDK/Features/UX/Scripts/Pointers/PokePointer.cs

@@ -224,9 +224,13 @@ private bool FindClosestTouchableForLayerMask(LayerMask layerMask, out BaseNearI
                 Camera mainCam = CameraCache.Main;
                 for (int i = 0; i < numColliders; ++i)
                 {
-                    var collider = queryBuffer[i];
-                    var touchable = collider.GetComponent<BaseNearInteractionTouchable>();
-                    if (touchable)
+                    Collider collider = queryBuffer[i];
+#if UNITY_2019_4_OR_NEWER
+                    if (collider.TryGetComponent(out BaseNearInteractionTouchable touchable) && touchable != null)
+#else
+                    BaseNearInteractionTouchable touchable = collider.GetComponent<BaseNearInteractionTouchable>();
+                    if (touchable != null)
+#endif
                     {
                         if (IgnoreCollidersNotInFOV && !mainCam.IsInFOVCached(collider))
                         {

Assets/MRTK/SDK/Features/UX/Scripts/Pointers/SpherePointer.cs

@@ -469,14 +469,11 @@ public SpherePointerQueryInfo(int bufferSize, float radius, float angle, float m
 
             public bool HasValidGrabbable(Vector3 pointerPosition, Vector3 pointerAxis, bool ignoreCollidersNotInFOV, LRUCache<int, NearInteractionGrabbable> componentCache)
             {
-                Vector3 grabbablePosition = pointerPosition;
-                NearInteractionGrabbable currentGrabbable = null;
-
                 for (int i = 0; i < numColliders; i++)
                 {
                     Collider collider = queryBuffer[i];
-                    if (IsColliderValidGrabbable(collider, ignoreCollidersNotInFOV, out currentGrabbable, componentCache)
-                        && IsColliderPositionValid(collider, pointerPosition, pointerAxis, queryAngle, queryMinDistance, out grabbablePosition))
+                    if (IsColliderValidGrabbable(collider, ignoreCollidersNotInFOV, out NearInteractionGrabbable currentGrabbable, componentCache)
+                        && IsColliderPositionValid(collider, pointerPosition, pointerAxis, queryAngle, queryMinDistance, out _))
                     {
                         if (currentGrabbable != null)
                         {
@@ -584,17 +581,23 @@ public void TryUpdateQueryBufferForLayerMask(LayerMask layerMask, Vector3 pointe
             public bool IsColliderValidGrabbable(Collider collider, bool ignoreCollidersNotInFOV, out NearInteractionGrabbable currentGrabbable, LRUCache<int, NearInteractionGrabbable> componentCache)
             {
                 // Check if the collider has a grabbable component which is valid
+                bool isValidGrabbable = true;
                 int instanceId = collider.gameObject.GetInstanceID();
                 if (!componentCache.TryGetValue(instanceId, out currentGrabbable))
                 {
-                    currentGrabbable = collider.gameObject.GetComponent<NearInteractionGrabbable>();
+#if UNITY_2019_4_OR_NEWER
+                    isValidGrabbable &= collider.TryGetComponent(out currentGrabbable);
+#else
+                    currentGrabbable = collider.GetComponent<NearInteractionGrabbable>();
+#endif
                     if (currentGrabbable != null)
                     {
                         componentCache.Add(instanceId, currentGrabbable);
                     }
                 }
 
-                bool isValidGrabbable = (currentGrabbable != null) && !(ignoreBoundsHandlesForQuery && currentGrabbable.IsBoundsHandles);
+                isValidGrabbable &= (currentGrabbable != null) && !(ignoreBoundsHandlesForQuery && currentGrabbable.IsBoundsHandles);
+
                 if (!isValidGrabbable)
                 {
                     // Remove it from the cache if the grabbable is no longer valid for the object