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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)
, m_isSilent(true)
, m_isEffectivelyPlayingAudio(false)
, m_muted(false)
{
addInput(std::make_unique<AudioNodeInput>(this));
setNodeType(NodeTypeDestination);
}
AudioDestinationNode::~AudioDestinationNode()
{
uninitialize();
}
void AudioDestinationNode::render(AudioBus*, 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().isInitialized()) {
destinationBus->zero();
setIsSilent(true);
return;
}
ASSERT(numberOfFrames);
if (!numberOfFrames) {
destinationBus->zero();
setIsSilent(true);
return;
}
// Let the context take care of any business at the start of each render quantum.
context().handlePreRenderTasks();
// 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;
setIsSilent(destinationBus->isSilent());
// The reason we are handling mute after the call to setIsSilent() is because the muted state does
// not affect the audio destination node's effective playing state.
if (m_muted)
destinationBus->zero();
}
void AudioDestinationNode::isPlayingDidChange()
{
updateIsEffectivelyPlayingAudio();
}
void AudioDestinationNode::setIsSilent(bool isSilent)
{
if (m_isSilent == isSilent)
return;
m_isSilent = isSilent;
updateIsEffectivelyPlayingAudio();
}
void AudioDestinationNode::updateIsEffectivelyPlayingAudio()
{
bool isEffectivelyPlayingAudio = isPlaying() && !m_isSilent;
if (m_isEffectivelyPlayingAudio == isEffectivelyPlayingAudio)
return;
m_isEffectivelyPlayingAudio = isEffectivelyPlayingAudio;
context().isPlayingAudioDidChange();
}
} // namespace WebCore
#endif // ENABLE(WEB_AUDIO)
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