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..c33c43e572abdc801ad5762d8b0c89b0e4802087 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 +434,69 @@ 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()
+{
+    if (m_cachedPosition != m_position)

[Raymond Toy, 2014/03/10 20:47:20]

Nit:  Add comment:

// Do a quick test and return if possible.

Add similar comment to isDistanceConeGainDirty and isDopplerDirty. Since the
original discussion of this is gone, a comment here is useful so future
developers don't combine them into one.

Recall that boolean operations shortcut, so you could combine the two if
statements into one big if statement and there's no loss in speed.

[KhNo, 2014/03/11 05:32:12]

Done.

+        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()
+{
+    if (m_cachedPosition != m_position || m_cachedOrientation != m_orientation)
+        return true;
+
+    if (m_cachedListener->position() != listener()->position())
+        return true;
+
+    return false;
+}
+
+bool PannerNode::isDopplerRateDirty()
+{
+    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 +529,23 @@ 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)