/* * Copyright (C) 2012, 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. */ #pragma once #include "AudioScheduledSourceNode.h" #include <wtf/Lock.h> namespace WebCore { class PeriodicWave; // OscillatorNode is an audio generator of periodic waveforms. class OscillatorNode final : public AudioScheduledSourceNode { public: // The waveform type. enum class Type { Sine, Square, Sawtooth, Triangle, Custom }; static Ref<OscillatorNode> create(AudioContext&, float sampleRate); virtual ~OscillatorNode(); Type type() const { return m_type; } ExceptionOr<void> setType(Type); AudioParam* frequency() { return m_frequency.get(); } AudioParam* detune() { return m_detune.get(); } void setPeriodicWave(PeriodicWave*); private: OscillatorNode(AudioContext&, float sampleRate); void process(size_t framesToProcess) final; void reset() final; double tailTime() const final { return 0; } double latencyTime() const final { return 0; } // Returns true if there are sample-accurate timeline parameter changes. bool calculateSampleAccuratePhaseIncrements(size_t framesToProcess); bool propagatesSilence() const final; // One of the waveform types defined in the enum. Type m_type { Type::Sine }; // Frequency value in Hertz. RefPtr<AudioParam> m_frequency; // Detune value (deviating from the frequency) in Cents. RefPtr<AudioParam> m_detune; bool m_firstRender; // m_virtualReadIndex is a sample-frame index into our buffer representing the current playback position. // Since it's floating-point, it has sub-sample accuracy. double m_virtualReadIndex; // This synchronizes process(). mutable Lock m_processMutex; // Stores sample-accurate values calculated according to frequency and detune. AudioFloatArray m_phaseIncrements; AudioFloatArray m_detuneValues; RefPtr<PeriodicWave> m_periodicWave; // Cache the wave tables for different waveform types, except CUSTOM. static PeriodicWave* s_periodicWaveSine; static PeriodicWave* s_periodicWaveSquare; static PeriodicWave* s_periodicWaveSawtooth; static PeriodicWave* s_periodicWaveTriangle; }; } // namespace WebCore