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/*
* Copyright (C) 2010, Google Inc. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS'' AND ANY
* EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS BE LIABLE FOR ANY
* DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
* ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include "config.h"
#if ENABLE(WEB_AUDIO)
#include "AudioDestinationNode.h"
#include "AudioContext.h"
#include "AudioNodeInput.h"
#include "AudioNodeOutput.h"
#include "AudioUtilities.h"
#include "DenormalDisabler.h"
namespace WebCore {
AudioDestinationNode::AudioDestinationNode(AudioContext* context, float sampleRate)
: AudioNode(context, sampleRate)
, m_currentSampleFrame(0)
{
addInput(adoptPtr(new AudioNodeInput(this)));
setNodeType(NodeTypeDestination);
}
AudioDestinationNode::~AudioDestinationNode()
{
uninitialize();
}
void AudioDestinationNode::render(AudioBus* sourceBus, AudioBus* destinationBus, size_t numberOfFrames)
{
// We don't want denormals slowing down any of the audio processing
// since they can very seriously hurt performance.
// This will take care of all AudioNodes because they all process within this scope.
DenormalDisabler denormalDisabler;
context()->setAudioThread(currentThread());
if (!context()->isRunnable()) {
destinationBus->zero();
return;
}
if (context()->userGestureRequiredForAudioStart()) {
destinationBus->zero();
return;
}
if (context()->pageConsentRequiredForAudioStart()) {
destinationBus->zero();
return;
}
// Let the context take care of any business at the start of each render quantum.
context()->handlePreRenderTasks();
// Prepare the local audio input provider for this render quantum.
if (sourceBus)
m_localAudioInputProvider.set(sourceBus);
// This will cause the node(s) connected to us to process, which in turn will pull on their input(s),
// all the way backwards through the rendering graph.
AudioBus* renderedBus = input(0)->pull(destinationBus, numberOfFrames);
if (!renderedBus)
destinationBus->zero();
else if (renderedBus != destinationBus) {
// in-place processing was not possible - so copy
destinationBus->copyFrom(*renderedBus);
}
// Process nodes which need a little extra help because they are not connected to anything, but still need to process.
context()->processAutomaticPullNodes(numberOfFrames);
// Let the context take care of any business at the end of each render quantum.
context()->handlePostRenderTasks();
// Advance current sample-frame.
m_currentSampleFrame += numberOfFrames;
}
} // namespace WebCore
#endif // ENABLE(WEB_AUDIO)
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