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29 #include "AudioDestinationNode.h"
32 #include "AudioContext.h"
33 #include "AudioNodeInput.h"
34 #include "AudioNodeOutput.h"
35 #include "DenormalDisabler.h"
39 AudioDestinationNode::AudioDestinationNode(AudioContext* context, double sampleRate)
40 : AudioNode(context, sampleRate)
43 addInput(adoptPtr(new AudioNodeInput(this)));
45 setType(NodeTypeDestination);
48 AudioDestinationNode::~AudioDestinationNode()
53 // The audio hardware calls us back here to gets its input stream.
54 void AudioDestinationNode::provideInput(AudioBus* destinationBus, size_t numberOfFrames)
56 // We don't want denormals slowing down any of the audio processing
57 // since they can very seriously hurt performance.
58 // This will take care of all AudioNodes because they all process within this scope.
59 DenormalDisabler denormalDisabler;
61 context()->setAudioThread(currentThread());
63 if (!context()->isRunnable()) {
64 destinationBus->zero();
68 // Let the context take care of any business at the start of each render quantum.
69 context()->handlePreRenderTasks();
71 // This will cause the node(s) connected to us to process, which in turn will pull on their input(s),
72 // all the way backwards through the rendering graph.
73 AudioBus* renderedBus = input(0)->pull(destinationBus, numberOfFrames);
76 destinationBus->zero();
77 else if (renderedBus != destinationBus) {
78 // in-place processing was not possible - so copy
79 destinationBus->copyFrom(*renderedBus);
82 // Let the context take care of any business at the end of each render quantum.
83 context()->handlePostRenderTasks();
85 // Advance current time.
86 m_currentTime += numberOfFrames / sampleRate();
89 } // namespace WebCore
91 #endif // ENABLE(WEB_AUDIO)