1 /* 2 * Copyright (C) 2011 Google Inc. All rights reserved. 3 * 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that the following conditions 6 * are met: 7 * 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. Neither the name of Apple Computer, Inc. ("Apple") nor the names of 14 * its contributors may be used to endorse or promote products derived 15 * from this software without specific prior written permission. 16 * 17 * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY 18 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED 19 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE 20 * DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY 21 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES 22 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 23 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND 24 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 26 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 27 */ 28 29 #ifndef AudioParamTimeline_h 30 #define AudioParamTimeline_h 31 32 #include "modules/webaudio/AudioContext.h" 33 #include "wtf/Float32Array.h" 34 #include "wtf/PassRefPtr.h" 35 #include "wtf/RefCounted.h" 36 #include "wtf/Threading.h" 37 #include "wtf/Vector.h" 38 39 namespace WebCore { 40 41 class AudioParamTimeline { 42 public: AudioParamTimeline()43 AudioParamTimeline() 44 { 45 } 46 47 void setValueAtTime(float value, double time); 48 void linearRampToValueAtTime(float value, double time); 49 void exponentialRampToValueAtTime(float value, double time, ExceptionState&); 50 void setTargetAtTime(float target, double time, double timeConstant); 51 void setValueCurveAtTime(Float32Array* curve, double time, double duration); 52 void cancelScheduledValues(double startTime); 53 54 // hasValue is set to true if a valid timeline value is returned. 55 // otherwise defaultValue is returned. 56 float valueForContextTime(AudioContext*, float defaultValue, bool& hasValue); 57 58 // Given the time range, calculates parameter values into the values buffer 59 // and returns the last parameter value calculated for "values" or the defaultValue if none were calculated. 60 // controlRate is the rate (number per second) at which parameter values will be calculated. 61 // It should equal sampleRate for sample-accurate parameter changes, and otherwise will usually match 62 // the render quantum size such that the parameter value changes once per render quantum. 63 float valuesForTimeRange(double startTime, double endTime, float defaultValue, float* values, unsigned numberOfValues, double sampleRate, double controlRate); 64 hasValues()65 bool hasValues() { return m_events.size(); } 66 67 private: 68 class ParamEvent { 69 public: 70 enum Type { 71 SetValue, 72 LinearRampToValue, 73 ExponentialRampToValue, 74 SetTarget, 75 SetValueCurve, 76 LastType 77 }; 78 ParamEvent(Type type,float value,double time,double timeConstant,double duration,PassRefPtr<Float32Array> curve)79 ParamEvent(Type type, float value, double time, double timeConstant, double duration, PassRefPtr<Float32Array> curve) 80 : m_type(type) 81 , m_value(value) 82 , m_time(time) 83 , m_timeConstant(timeConstant) 84 , m_duration(duration) 85 , m_curve(curve) 86 { 87 } 88 type()89 unsigned type() const { return m_type; } value()90 float value() const { return m_value; } time()91 double time() const { return m_time; } timeConstant()92 double timeConstant() const { return m_timeConstant; } duration()93 double duration() const { return m_duration; } curve()94 Float32Array* curve() { return m_curve.get(); } 95 96 private: 97 unsigned m_type; 98 float m_value; 99 double m_time; 100 double m_timeConstant; 101 double m_duration; 102 RefPtr<Float32Array> m_curve; 103 }; 104 105 void insertEvent(const ParamEvent&); 106 float valuesForTimeRangeImpl(double startTime, double endTime, float defaultValue, float* values, unsigned numberOfValues, double sampleRate, double controlRate); 107 108 Vector<ParamEvent> m_events; 109 110 Mutex m_eventsLock; 111 }; 112 113 } // namespace WebCore 114 115 #endif // AudioParamTimeline_h 116