Initial Commit

Assets/Oculus/Interaction/Runtime/Scripts/Selection/Hands/IndexPinchSafeReleaseSelector.cs

@@ -0,0 +1,184 @@
+/*
+ * Copyright (c) Meta Platforms, Inc. and affiliates.
+ * All rights reserved.
+ *
+ * Licensed under the Oculus SDK License Agreement (the "License");
+ * you may not use the Oculus SDK except in compliance with the License,
+ * which is provided at the time of installation or download, or which
+ * otherwise accompanies this software in either electronic or hard copy form.
+ *
+ * You may obtain a copy of the License at
+ *
+ * https://developer.oculus.com/licenses/oculussdk/
+ *
+ * Unless required by applicable law or agreed to in writing, the Oculus SDK
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+using Oculus.Interaction.Input;
+using System;
+using UnityEngine;
+
+namespace Oculus.Interaction
+{
+    /// <summary>
+    /// This Selector selects for a frame when the Pinch is released, as opposed to when it is pinching.
+    /// It uses the system pinch (index and thumb) but due to some false-positives with pinch detection,
+    /// to establish that a pinch has released the index must be not pinching and be extended.
+    /// </summary>
+    public class IndexPinchSafeReleaseSelector : MonoBehaviour,
+        ISelector, IActiveState
+    {
+        [SerializeField, Interface(typeof(IHand))]
+        private UnityEngine.Object _hand;
+        public IHand Hand { get; private set; }
+
+        [SerializeField]
+        private bool _selectOnRelease = true;
+
+        public bool Active => this.enabled && _isIndexFingerPinching && !_cancelled;
+
+        [SerializeField, Interface(typeof(IActiveState))]
+        private UnityEngine.Object _indexReleaseSafeguard;
+        private IActiveState IndexReleaseSafeguard;
+
+        private bool _isIndexFingerPinching;
+        private bool _cancelled;
+        private bool _pendingUnselect;
+
+        public event Action WhenSelected = delegate { };
+        public event Action WhenUnselected = delegate { };
+
+        protected bool _started = false;
+
+        protected virtual void Awake()
+        {
+            Hand = _hand as IHand;
+            IndexReleaseSafeguard = _indexReleaseSafeguard as IActiveState;
+        }
+
+        protected virtual void Start()
+        {
+            this.BeginStart(ref _started);
+            this.AssertField(Hand, nameof(Hand));
+            this.EndStart(ref _started);
+        }
+
+        protected virtual void OnEnable()
+        {
+            if (_started)
+            {
+                Hand.WhenHandUpdated += HandleHandUpdated;
+                _isIndexFingerPinching = false;
+                _pendingUnselect = false;
+            }
+        }
+
+        protected virtual void OnDisable()
+        {
+            if (_started)
+            {
+                Hand.WhenHandUpdated -= HandleHandUpdated;
+            }
+        }
+
+        private void HandleHandUpdated()
+        {
+            bool isPinchDetected = Hand.GetIndexFingerIsPinching();
+            bool isReleaseDetected = !isPinchDetected && IndexReleaseSafeguard.Active;
+
+            if (_selectOnRelease)
+            {
+                ProcessSelectOnRelease(isPinchDetected, isReleaseDetected);
+            }
+            else
+            {
+                ProcessSelectOnPinch(isPinchDetected, isReleaseDetected);
+            }
+        }
+
+        private void ProcessSelectOnPinch(bool isPinchDetected, bool isReleaseDetected)
+        {
+            if (!_isIndexFingerPinching && isPinchDetected && !_cancelled)
+            {
+                _isIndexFingerPinching = true;
+                WhenSelected.Invoke();
+            }
+            else if (_isIndexFingerPinching && isReleaseDetected)
+            {
+                _isIndexFingerPinching = false;
+                WhenUnselected.Invoke();
+            }
+
+            if (!_isIndexFingerPinching && _cancelled)
+            {
+                _cancelled = false;
+            }
+        }
+
+        private void ProcessSelectOnRelease(bool isPinchDetected, bool isReleaseDetected)
+        {
+            if (!_isIndexFingerPinching && isPinchDetected)
+            {
+                _isIndexFingerPinching = true;
+            }
+
+            if (!_isIndexFingerPinching && _pendingUnselect)
+            {
+                _pendingUnselect = false;
+                WhenUnselected.Invoke();
+            }
+
+            if (_isIndexFingerPinching && isReleaseDetected)
+            {
+                _isIndexFingerPinching = false;
+                if (!_cancelled)
+                {
+                    WhenSelected.Invoke();
+                    _pendingUnselect = true;
+                }
+                _cancelled = false;
+            }
+        }
+
+        public void Cancel()
+        {
+            if (_isIndexFingerPinching)
+            {
+                _cancelled = true;
+            }
+        }
+
+        #region Inject
+
+        public void InjectAllIndexPinchSafeReleaseSelector(IHand hand,
+            bool selectOnRelease,
+            IActiveState indexReleaseSafeguard)
+        {
+            InjectHand(hand);
+            InjectSelectOnRelease(selectOnRelease);
+            InjectIndexReleaseSafeguard(indexReleaseSafeguard);
+        }
+
+        public void InjectHand(IHand hand)
+        {
+            _hand = hand as UnityEngine.Object;
+            Hand = hand;
+        }
+
+        public void InjectSelectOnRelease(bool selectOnRelease)
+        {
+            _selectOnRelease = selectOnRelease;
+        }
+
+        public void InjectIndexReleaseSafeguard(IActiveState indexReleaseSafeguard)
+        {
+            _indexReleaseSafeguard = indexReleaseSafeguard as UnityEngine.Object;
+            IndexReleaseSafeguard = indexReleaseSafeguard;
+        }
+        #endregion
+    }
+}