Changeset 142687 in webkit

Timestamp:

Feb 12, 2013 4:10:45 PM (11 years ago)

Author:

Raymond Toy

Message:

Synchronize setting of panner node model and processing
​https://bugs.webkit.org/show_bug.cgi?id=109599

Reviewed by Chris Rogers.

No new tests.

• Modules/webaudio/PannerNode.cpp:

(WebCore::PannerNode::process):
(WebCore::PannerNode::setPanningModel):

• Modules/webaudio/PannerNode.h:

Location:

trunk/Source/WebCore

Files:

• ChangeLog (modified) (1 diff)
• Modules/webaudio/PannerNode.cpp (modified) (2 diffs)
• Modules/webaudio/PannerNode.h (modified) (1 diff)

trunk/Source/WebCore/ChangeLog

@@ +1 @@
+2013-02-12  Raymond Toy  <rtoy@google.com>
+
+        Synchronize setting of panner node model and processing
+        https://bugs.webkit.org/show_bug.cgi?id=109599
+
+        Reviewed by Chris Rogers.
+
+        No new tests.
+
+        * Modules/webaudio/PannerNode.cpp:
+        (WebCore::PannerNode::process):
+        (WebCore::PannerNode::setPanningModel):
+        * Modules/webaudio/PannerNode.h:
+
 2013-02-12  Dean Jackson  <dino@apple.com>
 

trunk/Source/WebCore/Modules/webaudio/PannerNode.cpp

@@ -105 +105 @@
     }
 
-    // Apply the panning effect.
-    double azimuth;
-    double elevation;
-    getAzimuthElevation(&azimuth, &elevation);
-    m_panner->pan(azimuth, elevation, source, destination, framesToProcess);
-
-    // Get the distance and cone gain.
-    double totalGain = distanceConeGain();
-
-    // Snap to desired gain at the beginning.
-    if (m_lastGain == -1.0)
-        m_lastGain = totalGain;
+    // The audio thread can't block on this lock, so we call tryLock() instead.
+    MutexTryLocker tryLocker(m_pannerLock);
+    if (tryLocker.locked()) {
+        // Apply the panning effect.
+        double azimuth;
+        double elevation;
+        getAzimuthElevation(&azimuth, &elevation);
+        m_panner->pan(azimuth, elevation, source, destination, framesToProcess);
+
+        // Get the distance and cone gain.
+        double totalGain = distanceConeGain();
+
+        // Snap to desired gain at the beginning.
+        if (m_lastGain == -1.0)
+            m_lastGain = totalGain;
         
-    // Apply gain in-place with de-zippering.
-    destination->copyWithGainFrom(*destination, &m_lastGain, totalGain);
+        // Apply gain in-place with de-zippering.
+        destination->copyWithGainFrom(*destination, &m_lastGain, totalGain);
+    } else {
+        // Too bad - The tryLock() failed. We must be in the middle of changing the panner.
+        destination->zero();
+    }
 }
 
@@ -186 +193 @@
     case HRTF:
         if (!m_panner.get() || model != m_panningModel) {
+            // This synchronizes with process().
+            MutexLocker processLocker(m_pannerLock);
+            
             OwnPtr<Panner> newPanner = Panner::create(model, sampleRate());
             m_panner = newPanner.release();

trunk/Source/WebCore/Modules/webaudio/PannerNode.h

@@ -155 +155 @@
 
     unsigned m_connectionCount;
+
+    // Synchronize process() and setPanningModel() which can change the panner.
+    mutable Mutex m_pannerLock;
 };