introduce MovementConstraintType.FixDistanceFromHead in ManipulationHandler

Author: nonemec-havok

Assets/MixedRealityToolkit.SDK/Features/Input/Handlers/ManipulationHandler.cs

@@ -57,6 +57,10 @@ private enum TwoHandedManipulation
         [Tooltip("Constrain rotation along an axis")]
         private RotationConstraintType constraintOnRotation = RotationConstraintType.None;
 
+        [SerializeField]
+        [Tooltip("Constrain movement")]
+        private MovementConstraintType constraintOnMovement = MovementConstraintType.None;
+
         [SerializeField]
         private HandMovementType handMoveType = HandMovementType.OneAndTwoHanded;
 
@@ -88,7 +92,7 @@ private enum State
         private void Awake()
         {
             gazeHandHelper = new GazeHandHelper();
-            m_moveLogic = new TwoHandMoveLogic();
+            m_moveLogic = new TwoHandMoveLogic(constraintOnMovement);
             m_rotateLogic = new TwoHandRotateLogic(constraintOnRotation);
             m_scaleLogic = new TwoHandScaleLogic();
         }

Assets/MixedRealityToolkit/Definitions/Utilities/MovementConstraintType.cs

@@ -0,0 +1,11 @@
+// Copyright (c) Microsoft Corporation. All rights reserved.
+// Licensed under the MIT License. See LICENSE in the project root for license information.
+
+namespace Microsoft.MixedReality.Toolkit.Core.Definitions.Utilities
+{
+    public enum MovementConstraintType
+    {
+        None,
+        FixDistanceFromHead
+    }
+}

Assets/MixedRealityToolkit/Definitions/Utilities/MovementConstraintType.cs.meta

@@ -1,6 +1,7 @@
 // Copyright (c) Microsoft Corporation. All rights reserved.
 // Licensed under the MIT License. See LICENSE in the project root for license information.
 
+using Microsoft.MixedReality.Toolkit.Core.Definitions.Utilities;
 using UnityEngine;
 
 namespace Microsoft.MixedReality.Toolkit.Core.Utilities.Physics
@@ -17,9 +18,20 @@ namespace Microsoft.MixedReality.Toolkit.Core.Utilities.Physics
     public class TwoHandMoveLogic
     {
         private static readonly Vector3 offsetPosition = new Vector3(0, -0.2f, 0);
+        private readonly MovementConstraintType movementConstraint;
+
         private float handRefDistance;
         private float objRefDistance;
 
+        /// <summary>
+        /// Constructor.
+        /// </summary>
+        /// <param name="rotationConstraint"></param>
+        public TwoHandMoveLogic(MovementConstraintType _movementConstraint)
+        {
+            movementConstraint = _movementConstraint;
+        }
+
         /// <summary>
         /// The initial angle between the hand and the object
         /// </summary>
@@ -61,11 +73,17 @@ public Vector3 Update(Vector3 centroid, Vector3 manipulationObjectPosition)
             var targetDirection = Vector3.Normalize(gazeAngularOffset * newHandDirection);
             targetDirection = CameraCache.Main.transform.TransformDirection(targetDirection);
 
-            // Compute how far away the object should be based on the ratio of the current to original hand distance
-            var currentHandDistance = Vector3.Magnitude(newHandPosition - pivotPosition);
-            var distanceRatio = currentHandDistance / handRefDistance;
-            var distanceOffset = distanceRatio > 0 ? (distanceRatio - 1f) * DistanceScale : 0;
-            var targetDistance = objRefDistance + distanceOffset;
+            var targetDistance = objRefDistance;
+
+            if(movementConstraint != MovementConstraintType.FixDistanceFromHead)
+            {
+                // Compute how far away the object should be based on the ratio of the current to original hand distance
+                var currentHandDistance = Vector3.Magnitude(newHandPosition - pivotPosition);
+                var distanceRatio = currentHandDistance / handRefDistance;
+                var distanceOffset = distanceRatio > 0 ? (distanceRatio - 1f) * DistanceScale : 0;
+                targetDistance += distanceOffset;
+            }
+
             var newPosition = pivotPosition + (targetDirection * targetDistance);
             var newDistance = Vector3.Distance(newPosition, pivotPosition);