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* Copyright (C) 2010, Google Inc. All rights reserved.
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#ifndef AudioNodeInput_h
#define AudioNodeInput_h
#include "platform/audio/AudioBus.h"
#include "modules/webaudio/AudioNode.h"
#include "modules/webaudio/AudioSummingJunction.h"
#include "wtf/HashSet.h"
#include "wtf/Vector.h"
namespace WebCore {
class AudioNode;
class AudioNodeOutput;
// An AudioNodeInput represents an input to an AudioNode and can be connected from one or more AudioNodeOutputs.
// In the case of multiple connections, the input will act as a unity-gain summing junction, mixing all the outputs.
// The number of channels of the input's bus is the maximum of the number of channels of all its connections.
class AudioNodeInput FINAL : public AudioSummingJunction {
public:
explicit AudioNodeInput(AudioNode*);
// AudioSummingJunction
virtual bool canUpdateState() OVERRIDE { return !node()->isMarkedForDeletion(); }
virtual void didUpdate() OVERRIDE;
// Can be called from any thread.
AudioNode* node() const { return m_node; }
// Must be called with the context's graph lock.
void connect(AudioNodeOutput*);
void disconnect(AudioNodeOutput*);
// disable() will take the output out of the active connections list and set aside in a disabled list.
// enable() will put the output back into the active connections list.
// Must be called with the context's graph lock.
void enable(AudioNodeOutput*);
void disable(AudioNodeOutput*);
// pull() processes all of the AudioNodes connected to us.
// In the case of multiple connections it sums the result into an internal summing bus.
// In the single connection case, it allows in-place processing where possible using inPlaceBus.
// It returns the bus which it rendered into, returning inPlaceBus if in-place processing was performed.
// Called from context's audio thread.
AudioBus* pull(AudioBus* inPlaceBus, size_t framesToProcess);
// bus() contains the rendered audio after pull() has been called for each time quantum.
// Called from context's audio thread.
AudioBus* bus();
// updateInternalBus() updates m_internalSummingBus appropriately for the number of channels.
// This must be called when we own the context's graph lock in the audio thread at the very start or end of the render quantum.
void updateInternalBus();
// The number of channels of the connection with the largest number of channels.
unsigned numberOfChannels() const;
private:
AudioNode* m_node;
// m_disabledOutputs contains the AudioNodeOutputs which are disabled (will not be processed) by the audio graph rendering.
// But, from JavaScript's perspective, these outputs are still connected to us.
// Generally, these represent disabled connections from "notes" which have finished playing but are not yet garbage collected.
HashSet<AudioNodeOutput*> m_disabledOutputs;
// Called from context's audio thread.
AudioBus* internalSummingBus();
void sumAllConnections(AudioBus* summingBus, size_t framesToProcess);
RefPtr<AudioBus> m_internalSummingBus;
};
} // namespace WebCore
#endif // AudioNodeInput_h