Initial Commit

Assets/Oculus/Interaction/Runtime/Scripts/Unity/PhysicsGrabbable.cs

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+/*
+ * 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 System;
+using UnityEngine;
+using UnityEngine.Assertions;
+using UnityEngine.Serialization;
+
+namespace Oculus.Interaction
+{
+    public class PhysicsGrabbable : MonoBehaviour
+    {
+        [SerializeField]
+        private Grabbable _grabbable;
+
+        [SerializeField]
+        private Rigidbody _rigidbody;
+
+        [SerializeField]
+        [Tooltip("If enabled, the object's mass will scale appropriately as the scale of the object changes.")]
+        private bool _scaleMassWithSize = true;
+
+        private bool _savedIsKinematicState = false;
+        private bool _isBeingTransformed = false;
+        private Vector3 _initialScale;
+        private bool _hasPendingForce;
+        private Vector3 _linearVelocity;
+        private Vector3 _angularVelocity;
+
+        protected bool _started = false;
+
+        public event Action<Vector3, Vector3> WhenVelocitiesApplied = delegate { };
+
+        private void Reset()
+        {
+            _grabbable = this.GetComponent<Grabbable>();
+            _rigidbody = this.GetComponent<Rigidbody>();
+        }
+
+        protected virtual void Start()
+        {
+            this.BeginStart(ref _started);
+            this.AssertField(_grabbable, nameof(_grabbable));
+            this.AssertField(_rigidbody, nameof(_rigidbody));
+            this.EndStart(ref _started);
+        }
+
+        protected virtual void OnEnable()
+        {
+            if (_started)
+            {
+                _grabbable.WhenPointerEventRaised += HandlePointerEventRaised;
+            }
+        }
+
+        protected virtual void OnDisable()
+        {
+            if (_started)
+            {
+                _grabbable.WhenPointerEventRaised -= HandlePointerEventRaised;
+            }
+        }
+
+        private void HandlePointerEventRaised(PointerEvent evt)
+        {
+            switch (evt.Type)
+            {
+                case PointerEventType.Select:
+                    if (_grabbable.SelectingPointsCount == 1 && !_isBeingTransformed)
+                    {
+                        DisablePhysics();
+                    }
+
+                    break;
+                case PointerEventType.Unselect:
+                    if (_grabbable.SelectingPointsCount == 0)
+                    {
+                        ReenablePhysics();
+                    }
+
+                    break;
+            }
+        }
+
+        private void DisablePhysics()
+        {
+            _isBeingTransformed = true;
+            CachePhysicsState();
+            _rigidbody.isKinematic = true;
+        }
+
+        private void ReenablePhysics()
+        {
+            _isBeingTransformed = false;
+            // update the mass based on the scale change
+            if (_scaleMassWithSize)
+            {
+                float initialScaledVolume = _initialScale.x * _initialScale.y * _initialScale.z;
+
+                Vector3 currentScale = _rigidbody.transform.localScale;
+                float currentScaledVolume = currentScale.x * currentScale.y * currentScale.z;
+
+                float changeInMassFactor = currentScaledVolume / initialScaledVolume;
+                _rigidbody.mass *= changeInMassFactor;
+            }
+
+            // revert the original kinematic state
+            _rigidbody.isKinematic = _savedIsKinematicState;
+        }
+
+        public void ApplyVelocities(Vector3 linearVelocity, Vector3 angularVelocity)
+        {
+            _hasPendingForce = true;
+            _linearVelocity = linearVelocity;
+            _angularVelocity = angularVelocity;
+        }
+
+        private void FixedUpdate()
+        {
+            if (_hasPendingForce)
+            {
+                _hasPendingForce = false;
+                _rigidbody.AddForce(_linearVelocity, ForceMode.VelocityChange);
+                _rigidbody.AddTorque(_angularVelocity, ForceMode.VelocityChange);
+                WhenVelocitiesApplied(_linearVelocity, _angularVelocity);
+            }
+        }
+
+        private void CachePhysicsState()
+        {
+            _savedIsKinematicState = _rigidbody.isKinematic;
+            _initialScale = _rigidbody.transform.localScale;
+        }
+
+        #region Inject
+
+        public void InjectAllPhysicsGrabbable(Grabbable grabbable, Rigidbody rigidbody)
+        {
+            InjectGrabbable(grabbable);
+            InjectRigidbody(rigidbody);
+        }
+
+        public void InjectGrabbable(Grabbable grabbable)
+        {
+            _grabbable = grabbable;
+        }
+
+        public void InjectRigidbody(Rigidbody rigidbody)
+        {
+            _rigidbody = rigidbody;
+        }
+
+        public void InjectOptionalScaleMassWithSize(bool scaleMassWithSize)
+        {
+            _scaleMassWithSize = scaleMassWithSize;
+        }
+
+        #endregion
+    }
+}