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25 #ifndef OscillatorNode_h
26 #define OscillatorNode_h
28 #include "platform/audio/AudioBus.h"
29 #include "modules/webaudio/AudioParam.h"
30 #include "modules/webaudio/AudioScheduledSourceNode.h"
31 #include "wtf/OwnPtr.h"
32 #include "wtf/PassRefPtr.h"
33 #include "wtf/RefPtr.h"
34 #include "wtf/Threading.h"
41 // OscillatorNode is an audio generator of periodic waveforms.
43 class OscillatorNode FINAL : public AudioScheduledSourceNode {
46 // These must be defined as in the .idl file.
55 static PassRefPtrWillBeRawPtr<OscillatorNode> create(AudioContext*, float sampleRate);
57 virtual ~OscillatorNode();
60 virtual void process(size_t framesToProcess) OVERRIDE;
64 void setType(const String&);
66 AudioParam* frequency() { return m_frequency.get(); }
67 AudioParam* detune() { return m_detune.get(); }
69 void setPeriodicWave(PeriodicWave*);
71 virtual void trace(Visitor*) OVERRIDE;
74 OscillatorNode(AudioContext*, float sampleRate);
76 bool setType(unsigned); // Returns true on success.
78 // Returns true if there are sample-accurate timeline parameter changes.
79 bool calculateSampleAccuratePhaseIncrements(size_t framesToProcess);
81 virtual bool propagatesSilence() const OVERRIDE;
83 // One of the waveform types defined in the enum.
84 unsigned short m_type;
86 // Frequency value in Hertz.
87 RefPtrWillBeMember<AudioParam> m_frequency;
89 // Detune value (deviating from the frequency) in Cents.
90 RefPtrWillBeMember<AudioParam> m_detune;
94 // m_virtualReadIndex is a sample-frame index into our buffer representing the current playback position.
95 // Since it's floating-point, it has sub-sample accuracy.
96 double m_virtualReadIndex;
98 // This synchronizes process().
99 mutable Mutex m_processLock;
101 // Stores sample-accurate values calculated according to frequency and detune.
102 AudioFloatArray m_phaseIncrements;
103 AudioFloatArray m_detuneValues;
105 RefPtrWillBeMember<PeriodicWave> m_periodicWave;
108 } // namespace WebCore
110 #endif // OscillatorNode_h