Merge pull request #6673 from hyperlogic/tony/get-palm-thread-safe

Make Avatar palm position/rotation accessors thread safe

interface/src/avatar/Avatar.cpp

@@ -237,6 +237,7 @@ void Avatar::simulate(float deltaTime) {
     measureMotionDerivatives(deltaTime);
 
     simulateAttachments(deltaTime);
+    updatePalms();
 }
 
 bool Avatar::isLookingAtMe(AvatarSharedPointer avatar) const {
@@ -1155,34 +1156,24 @@ void Avatar::rebuildCollisionShape() {
     }
 }
 
+// thread-safe
 glm::vec3 Avatar::getLeftPalmPosition() {
-    glm::vec3 leftHandPosition;
-    getSkeletonModel().getLeftHandPosition(leftHandPosition);
-    glm::quat leftRotation;
-    getSkeletonModel().getJointRotationInWorldFrame(getSkeletonModel().getLeftHandJointIndex(), leftRotation);
-    leftHandPosition += HAND_TO_PALM_OFFSET * glm::inverse(leftRotation);
-    return leftHandPosition;
+    return _leftPalmPositionCache.get();
 }
 
+// thread-safe
 glm::quat Avatar::getLeftPalmRotation() {
-    glm::quat leftRotation;
-    getSkeletonModel().getJointRotationInWorldFrame(getSkeletonModel().getLeftHandJointIndex(), leftRotation);
-    return leftRotation;
+    return _leftPalmRotationCache.get();
 }
 
+// thread-safe
 glm::vec3 Avatar::getRightPalmPosition() {
-    glm::vec3 rightHandPosition;
-    getSkeletonModel().getRightHandPosition(rightHandPosition);
-    glm::quat rightRotation;
-    getSkeletonModel().getJointRotationInWorldFrame(getSkeletonModel().getRightHandJointIndex(), rightRotation);
-    rightHandPosition += HAND_TO_PALM_OFFSET * glm::inverse(rightRotation);
-    return rightHandPosition;
+    return _rightPalmPositionCache.get();
 }
 
+// thread-safe
 glm::quat Avatar::getRightPalmRotation() {
-    glm::quat rightRotation;
-    getSkeletonModel().getJointRotationInWorldFrame(getSkeletonModel().getRightHandJointIndex(), rightRotation);
-    return rightRotation;
+    return _rightPalmRotationCache.get();
 }
 
 void Avatar::setPosition(const glm::vec3& position) {
@@ -1194,3 +1185,24 @@ void Avatar::setOrientation(const glm::quat& orientation) {
     AvatarData::setOrientation(orientation);
     updateAttitude();
 }
+
+void Avatar::updatePalms() {
+
+    // get palm rotations
+    glm::quat leftPalmRotation, rightPalmRotation;
+    getSkeletonModel().getJointRotationInWorldFrame(getSkeletonModel().getLeftHandJointIndex(), leftPalmRotation);
+    getSkeletonModel().getJointRotationInWorldFrame(getSkeletonModel().getRightHandJointIndex(), rightPalmRotation);
+
+    // get palm positions
+    glm::vec3 leftPalmPosition, rightPalmPosition;
+    getSkeletonModel().getLeftHandPosition(leftPalmPosition);
+    getSkeletonModel().getRightHandPosition(rightPalmPosition);
+    leftPalmPosition += HAND_TO_PALM_OFFSET * glm::inverse(leftPalmRotation);
+    rightPalmPosition += HAND_TO_PALM_OFFSET * glm::inverse(rightPalmRotation);
+
+    // update thread-safe caches
+    _leftPalmRotationCache.set(leftPalmRotation);
+    _rightPalmRotationCache.set(rightPalmRotation);
+    _leftPalmPositionCache.set(leftPalmPosition);
+    _rightPalmPositionCache.set(rightPalmPosition);
+}

interface/src/avatar/Avatar.h

@@ -27,6 +27,7 @@
 #include "SkeletonModel.h"
 #include "world.h"
 #include "Rig.h"
+#include <ThreadSafeValueCache.h>
 
 namespace render {
     template <> const ItemKey payloadGetKey(const AvatarSharedPointer& avatar);
@@ -227,8 +228,15 @@ protected:
 
     virtual void updateJointMappings() override;
 
+    virtual void updatePalms();
+
     render::ItemID _renderItemID;
 
+    ThreadSafeValueCache<glm::vec3> _leftPalmPositionCache { glm::vec3() };
+    ThreadSafeValueCache<glm::quat> _leftPalmRotationCache { glm::quat() };
+    ThreadSafeValueCache<glm::vec3> _rightPalmPositionCache { glm::vec3() };
+    ThreadSafeValueCache<glm::quat> _rightPalmRotationCache { glm::quat() };
+
 private:
     bool _initialized;
     NetworkTexturePointer _billboardTexture;

interface/src/avatar/MyAvatar.cpp

@@ -417,6 +417,8 @@ void MyAvatar::updateSensorToWorldMatrix() {
     // position when driven from the head.
     glm::mat4 desiredMat = createMatFromQuatAndPos(getOrientation(), getPosition());
     _sensorToWorldMatrix = desiredMat * glm::inverse(_bodySensorMatrix);
+
+    lateUpdatePalms();
 }
 
 //  Update avatar head rotation with sensor data
@@ -1839,3 +1841,8 @@ QScriptValue audioListenModeToScriptValue(QScriptEngine* engine, const AudioList
 void audioListenModeFromScriptValue(const QScriptValue& object, AudioListenerMode& audioListenerMode) {
     audioListenerMode = (AudioListenerMode)object.toUInt16();
 }
+
+
+void MyAvatar::lateUpdatePalms() {
+    Avatar::updatePalms();
+}

interface/src/avatar/MyAvatar.h

@@ -311,12 +311,14 @@ private:
 
     void setVisibleInSceneIfReady(Model* model, render::ScenePointer scene, bool visiblity);
 
-    PalmData getActivePalmData(int palmIndex) const;
-
     // derive avatar body position and orientation from the current HMD Sensor location.
     // results are in HMD frame
     glm::mat4 deriveBodyFromHMDSensor() const;
 
+    virtual void updatePalms() override {}
+    void lateUpdatePalms();
+
+
     float _driveKeys[MAX_DRIVE_KEYS];
     bool _wasPushing;
     bool _isPushing;

libraries/shared/src/ThreadSafeValueCache.h

@@ -0,0 +1,49 @@
+//
+//  ThreadSafeValueCache.h
+//  interface/src/avatar
+//
+//  Copyright 2012 High Fidelity, Inc.
+//
+//  Distributed under the Apache License, Version 2.0.
+//  See the accompanying file LICENSE or http://www.apache.org/licenses/LICENSE-2.0.html
+//
+
+#ifndef hifi_ThreadSafeValueCache_h
+#define hifi_ThreadSafeValueCache_h
+
+#include <mutex>
+
+// Helper class for for sharing a value type between threads.
+// It allows many threads to get or set a value atomically.
+// This provides cache semantics, any get will return the last set value.
+//
+// For example: This can be used to copy values between C++ code running on the application thread
+// and JavaScript which is running on a different thread.
+
+template <typename T>
+class ThreadSafeValueCache {
+public:
+    ThreadSafeValueCache(const T& v) : _value { v } {}
+
+    // returns atomic copy of the cached value.
+    T get() const {
+        std::lock_guard<std::mutex> guard(_mutex);
+        return _value;
+    }
+
+    // will reflect copy of value into the cache.
+    void set(const T& v) {
+        std::lock_guard<std::mutex> guard(_mutex);
+        _value = v;
+    }
+
+private:
+    mutable std::mutex _mutex;
+    T _value;
+
+    // no copies
+    ThreadSafeValueCache(const ThreadSafeValueCache&) = delete;
+    ThreadSafeValueCache& operator=(const ThreadSafeValueCache&) = delete;
+};
+
+#endif // #define hifi_ThreadSafeValueCache_h