Cache values for panning and spatialization effects to enhance performance on pannerNode.

Source/modules/webaudio/PannerNode.cpp

Index: Source/modules/webaudio/PannerNode.cpp
diff --git a/Source/modules/webaudio/PannerNode.cpp b/Source/modules/webaudio/PannerNode.cpp
index 27e06244babb4cedc8f5a3bf61d400684df839df..3f2dde89def0dc6e3f5920d71ebb7663e6bd3d12 100644
--- a/Source/modules/webaudio/PannerNode.cpp
+++ b/Source/modules/webaudio/PannerNode.cpp
@@ -49,7 +49,17 @@ static void fixNANs(double &x)
 PannerNode::PannerNode(AudioContext* context, float sampleRate)
     : AudioNode(context, sampleRate)
     , m_panningModel(Panner::PanningModelHRTF)
+    , m_position(0, 0, 0)
+    , m_orientation(1, 0, 0)
+    , m_velocity(0, 0, 0)
+    , m_cachedPosition(0, 0, 0)
+    , m_cachedOrientation(1, 0, 0)
+    , m_cachedVelocity(0, 0, 0)
     , m_lastGain(-1.0)
+    , m_cachedAzimuth(0)
+    , m_cachedElevation(0)
+    , m_cachedDistanceConeGain(0)
+    , m_cachedDopplerRate(1)
     , m_connectionCount(0)
 {
     // Load the HRTF database asynchronously so we don't block the Javascript thread while creating the HRTF database.
@@ -68,9 +78,7 @@ PannerNode::PannerNode(AudioContext* context, float sampleRate)
     m_distanceGain = AudioParam::create(context, "distanceGain", 1.0, 0.0, 1.0);
     m_coneGain = AudioParam::create(context, "coneGain", 1.0, 0.0, 1.0);
 
-    m_position = FloatPoint3D(0, 0, 0);
-    m_orientation = FloatPoint3D(1, 0, 0);
-    m_velocity = FloatPoint3D(0, 0, 0);
+    m_cachedListener = AudioListener::create();
 
     setNodeType(NodeTypePanner);
 
@@ -131,11 +139,12 @@ void PannerNode::process(size_t framesToProcess)
         // Apply the panning effect.
         double azimuth;
         double elevation;
-        getAzimuthElevation(&azimuth, &elevation);
+        azimuthElevation(&azimuth, &elevation);
+
         m_panner->pan(azimuth, elevation, source, destination, framesToProcess);
 
         // Get the distance and cone gain.
-        double totalGain = distanceConeGain();
+        float totalGain = distanceConeGain();
 
         // Snap to desired gain at the beginning.
         if (m_lastGain == -1.0)
@@ -143,6 +152,11 @@ void PannerNode::process(size_t framesToProcess)
 
         // Apply gain in-place with de-zippering.
         destination->copyWithGainFrom(*destination, &m_lastGain, totalGain);
+
+        // Update the cached listener in case listener has moved.
+        updateCachedListener();
+        // Now update the cached source location in case the source has changed.
+        updateCachedSourceLocationInfo();
     } else {
         // Too bad - The tryLock() failed. We must be in the middle of changing the panner.
         destination->zero();
@@ -217,6 +231,42 @@ bool PannerNode::setPanningModel(unsigned model)
     return true;
 }
 
+void PannerNode::setPosition(float x, float y, float z)
+{
+    // FIXME : consider thread safety about m_position in audio thread.
+    // See http://crbugs.com/350583.
+    FloatPoint3D position = FloatPoint3D(x, y, z);
+
+    if (m_position == position)
+        return;
+
+    m_position = position;
+}
+
+void PannerNode::setOrientation(float x, float y, float z)
+{
+    // FIXME : consider thread safety about m_orientation in audio thread.
+    // See http://crbugs.com/350583.
+    FloatPoint3D orientation = FloatPoint3D(x, y, z);
+
+    if (m_orientation == orientation)
+        return;
+
+    m_orientation = orientation;
+}
+
+void PannerNode::setVelocity(float x, float y, float z)
+{
+    // FIXME : consider thread safety about m_velocity in audio thread.
+    // See http://crbugs.com/350583.
+    FloatPoint3D velocity = FloatPoint3D(x, y, z);
+
+    if (m_velocity == velocity)
+        return;
+
+    m_velocity = velocity;
+}
+
 String PannerNode::distanceModel() const
 {
     switch (const_cast<PannerNode*>(this)->m_distanceEffect.model()) {
@@ -259,10 +309,8 @@ bool PannerNode::setDistanceModel(unsigned model)
     return true;
 }
 
-void PannerNode::getAzimuthElevation(double* outAzimuth, double* outElevation)
+void PannerNode::calculateAzimuthElevation(double* outAzimuth, double* outElevation)
 {
-    // FIXME: we should cache azimuth and elevation (if possible), so we only re-calculate if a change has been made.
-
     double azimuth = 0.0;
 
     // Calculate the source-listener vector
@@ -323,11 +371,10 @@ void PannerNode::getAzimuthElevation(double* outAzimuth, double* outElevation)
         *outElevation = elevation;
 }
 
-float PannerNode::dopplerRate()
+
+double PannerNode::calculateDopplerRate()
 {
     double dopplerShift = 1.0;
-
-    // FIXME: optimize for case when neither source nor listener has changed...
     double dopplerFactor = listener()->dopplerFactor();
 
     if (dopplerFactor > 0.0) {
@@ -368,10 +415,10 @@ float PannerNode::dopplerRate()
         }
     }
 
-    return static_cast<float>(dopplerShift);
+    return dopplerShift;
 }
 
-float PannerNode::distanceConeGain()
+float PannerNode::calculateDistanceConeGain()
 {
     FloatPoint3D listenerPosition = listener()->position();
 
@@ -380,7 +427,6 @@ float PannerNode::distanceConeGain()
 
     m_distanceGain->setValue(static_cast<float>(distanceGain));
 
-    // FIXME: could optimize by caching coneGain
     double coneGain = m_coneEffect.gain(m_position, m_orientation, listenerPosition);
 
     m_coneGain->setValue(static_cast<float>(coneGain));
@@ -388,6 +434,72 @@ float PannerNode::distanceConeGain()
     return float(distanceGain * coneGain);
 }
 
+void PannerNode::azimuthElevation(double* outAzimuth, double* outElevation)
+{
+    if (isAzimuthElevationDirty())
+        calculateAzimuthElevation(&m_cachedAzimuth, &m_cachedElevation);
+
+    *outAzimuth = m_cachedAzimuth;
+    *outElevation = m_cachedElevation;
+}
+
+double PannerNode::dopplerRate()
+{
+    if (isDopplerRateDirty())
+        m_cachedDopplerRate = calculateDopplerRate();
+
+    return m_cachedDopplerRate;
+}
+
+float PannerNode::distanceConeGain()
+{
+    if (isDistanceConeGainDirty())
+        m_cachedDistanceConeGain = calculateDistanceConeGain();
+
+    return m_cachedDistanceConeGain;
+}
+
+bool PannerNode::isAzimuthElevationDirty()
+{
+    // Do a quick test and return if possible.
+    if (m_cachedPosition != m_position)
+        return true;
+
+    if (m_cachedListener->position() != listener()->position()
+        || m_cachedListener->orientation() != listener()->orientation()
+        || m_cachedListener->upVector() != listener()->upVector())
+        return true;
+
+    return false;
+}
+
+bool PannerNode::isDistanceConeGainDirty()
+{
+    // Do a quick test and return if possible.
+    if (m_cachedPosition != m_position || m_cachedOrientation != m_orientation)
+        return true;
+
+    if (m_cachedListener->position() != listener()->position())
+        return true;
+
+    return false;
+}
+
+bool PannerNode::isDopplerRateDirty()
+{
+    // Do a quick test and return if possible.
+    if (m_cachedPosition != m_position || m_cachedVelocity != m_velocity)
+        return true;
+
+    if (m_cachedListener->position() != listener()->position()
+        || m_cachedListener->velocity() != listener()->velocity()
+        || m_cachedListener->dopplerFactor() != listener()->dopplerFactor()
+        || m_cachedListener->speedOfSound() != listener()->speedOfSound())
+        return true;
+
+    return false;
+}
+
 void PannerNode::notifyAudioSourcesConnectedToNode(AudioNode* node, HashMap<AudioNode*, bool>& visitedNodes)
 {
     ASSERT(node);
@@ -420,6 +532,23 @@ void PannerNode::notifyAudioSourcesConnectedToNode(AudioNode* node, HashMap<Audi
     }
 }
 
+void PannerNode::updateCachedListener()
+{
+    m_cachedListener->setPosition(listener()->position());
+    m_cachedListener->setOrientation(listener()->orientation());
+    m_cachedListener->setUpVector(listener()->upVector());
+    m_cachedListener->setVelocity(listener()->velocity());
+    m_cachedListener->setDopplerFactor(listener()->dopplerFactor());
+    m_cachedListener->setSpeedOfSound(listener()->speedOfSound());
+}
+
+void PannerNode::updateCachedSourceLocationInfo()
+{
+    m_cachedPosition = m_position;
+    m_cachedOrientation = m_orientation;
+    m_cachedVelocity = m_velocity;
+}
+
 } // namespace WebCore
 
 #endif // ENABLE(WEB_AUDIO)