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 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#pragma once
30
31#include "AudioContext.h"
32#include <JavaScriptCore/Float32Array.h>
33#include <wtf/Lock.h>
34#include <wtf/Vector.h>
35
36namespace WebCore {
37
38class AudioParamTimeline {
39 WTF_MAKE_NONCOPYABLE(AudioParamTimeline);
40 WTF_MAKE_FAST_ALLOCATED;
41public:
42 AudioParamTimeline()
43 {
44 }
45
46 void setValueAtTime(float value, float time);
47 void linearRampToValueAtTime(float value, float time);
48 void exponentialRampToValueAtTime(float value, float time);
49 void setTargetAtTime(float target, float time, float timeConstant);
50 void setValueCurveAtTime(Float32Array* curve, float time, float duration);
51 void cancelScheduledValues(float startTime);
52
53 // hasValue is set to true if a valid timeline value is returned.
54 // otherwise defaultValue is returned.
55 float valueForContextTime(AudioContext&, float defaultValue, bool& hasValue);
56
57 // Given the time range, calculates parameter values into the values buffer
58 // and returns the last parameter value calculated for "values" or the defaultValue if none were calculated.
59 // controlRate is the rate (number per second) at which parameter values will be calculated.
60 // It should equal sampleRate for sample-accurate parameter changes, and otherwise will usually match
61 // the render quantum size such that the parameter value changes once per render quantum.
62 float valuesForTimeRange(double startTime, double endTime, float defaultValue, float* values, unsigned numberOfValues, double sampleRate, double controlRate);
63
64 bool hasValues() { return m_events.size(); }
65
66private:
67 class ParamEvent {
68 public:
69 enum Type {
70 SetValue,
71 LinearRampToValue,
72 ExponentialRampToValue,
73 SetTarget,
74 SetValueCurve,
75 LastType
76 };
77
78 ParamEvent(Type type, float value, float time, float timeConstant, float duration, RefPtr<Float32Array>&& curve)
79 : m_type(type)
80 , m_value(value)
81 , m_time(time)
82 , m_timeConstant(timeConstant)
83 , m_duration(duration)
84 , m_curve(WTFMove(curve))
85 {
86 }
87
88 unsigned type() const { return m_type; }
89 float value() const { return m_value; }
90 float time() const { return m_time; }
91 float timeConstant() const { return m_timeConstant; }
92 float duration() const { return m_duration; }
93 Float32Array* curve() { return m_curve.get(); }
94
95 private:
96 unsigned m_type;
97 float m_value;
98 float m_time;
99 float m_timeConstant;
100 float m_duration;
101 RefPtr<Float32Array> m_curve;
102 };
103
104 void insertEvent(const ParamEvent&);
105 float valuesForTimeRangeImpl(double startTime, double endTime, float defaultValue, float* values, unsigned numberOfValues, double sampleRate, double controlRate);
106
107 Vector<ParamEvent> m_events;
108
109 Lock m_eventsMutex;
110};
111
112} // namespace WebCore
113