1/*
2 * Copyright (C) 2010, 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 * 1. Redistributions of source code must retain the above copyright
8 * notice, this list of conditions and the following disclaimer.
9 * 2. Redistributions in binary form must reproduce the above copyright
10 * notice, this list of conditions and the following disclaimer in the
11 * documentation and/or other materials provided with the distribution.
12 *
13 * THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS'' AND ANY
14 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
15 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
16 * DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS BE LIABLE FOR ANY
17 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
18 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
19 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
20 * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
21 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
22 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
23 */
24
25#include "config.h"
26
27#if ENABLE(WEB_AUDIO)
28
29#include "AudioNodeOutput.h"
30
31#include "AudioBus.h"
32#include "AudioContext.h"
33#include "AudioNodeInput.h"
34#include "AudioParam.h"
35#include <wtf/Threading.h>
36
37namespace WebCore {
38
39AudioNodeOutput::AudioNodeOutput(AudioNode* node, unsigned numberOfChannels)
40 : m_node(node)
41 , m_numberOfChannels(numberOfChannels)
42 , m_desiredNumberOfChannels(numberOfChannels)
43 , m_isInPlace(false)
44 , m_isEnabled(true)
45 , m_renderingFanOutCount(0)
46 , m_renderingParamFanOutCount(0)
47{
48 ASSERT(numberOfChannels <= AudioContext::maxNumberOfChannels());
49
50 m_internalBus = AudioBus::create(numberOfChannels, AudioNode::ProcessingSizeInFrames);
51}
52
53void AudioNodeOutput::setNumberOfChannels(unsigned numberOfChannels)
54{
55 ASSERT(numberOfChannels <= AudioContext::maxNumberOfChannels());
56 ASSERT(context().isGraphOwner());
57
58 m_desiredNumberOfChannels = numberOfChannels;
59
60 if (context().isAudioThread()) {
61 // If we're in the audio thread then we can take care of it right away (we should be at the very start or end of a rendering quantum).
62 updateNumberOfChannels();
63 } else {
64 // Let the context take care of it in the audio thread in the pre and post render tasks.
65 context().markAudioNodeOutputDirty(this);
66 }
67}
68
69void AudioNodeOutput::updateInternalBus()
70{
71 if (numberOfChannels() == m_internalBus->numberOfChannels())
72 return;
73
74 m_internalBus = AudioBus::create(numberOfChannels(), AudioNode::ProcessingSizeInFrames);
75}
76
77void AudioNodeOutput::updateRenderingState()
78{
79 updateNumberOfChannels();
80 m_renderingFanOutCount = fanOutCount();
81 m_renderingParamFanOutCount = paramFanOutCount();
82}
83
84void AudioNodeOutput::updateNumberOfChannels()
85{
86 ASSERT(context().isAudioThread() && context().isGraphOwner());
87
88 if (m_numberOfChannels != m_desiredNumberOfChannels) {
89 m_numberOfChannels = m_desiredNumberOfChannels;
90 updateInternalBus();
91 propagateChannelCount();
92 }
93}
94
95void AudioNodeOutput::propagateChannelCount()
96{
97 ASSERT(context().isAudioThread() && context().isGraphOwner());
98
99 if (isChannelCountKnown()) {
100 // Announce to any nodes we're connected to that we changed our channel count for its input.
101 for (auto& input : m_inputs) {
102 AudioNode* connectionNode = input->node();
103 connectionNode->checkNumberOfChannelsForInput(input);
104 }
105 }
106}
107
108AudioBus* AudioNodeOutput::pull(AudioBus* inPlaceBus, size_t framesToProcess)
109{
110 ASSERT(context().isAudioThread());
111 ASSERT(m_renderingFanOutCount > 0 || m_renderingParamFanOutCount > 0);
112
113 // Causes our AudioNode to process if it hasn't already for this render quantum.
114 // We try to do in-place processing (using inPlaceBus) if at all possible,
115 // but we can't process in-place if we're connected to more than one input (fan-out > 1).
116 // In this case pull() is called multiple times per rendering quantum, and the processIfNecessary() call below will
117 // cause our node to process() only the first time, caching the output in m_internalOutputBus for subsequent calls.
118
119 m_isInPlace = inPlaceBus && inPlaceBus->numberOfChannels() == numberOfChannels() && (m_renderingFanOutCount + m_renderingParamFanOutCount) == 1;
120
121 m_inPlaceBus = m_isInPlace ? inPlaceBus : 0;
122
123 node()->processIfNecessary(framesToProcess);
124 return bus();
125}
126
127AudioBus* AudioNodeOutput::bus() const
128{
129 ASSERT(const_cast<AudioNodeOutput*>(this)->context().isAudioThread());
130 return m_isInPlace ? m_inPlaceBus.get() : m_internalBus.get();
131}
132
133unsigned AudioNodeOutput::fanOutCount()
134{
135 ASSERT(context().isGraphOwner());
136 return m_inputs.size();
137}
138
139unsigned AudioNodeOutput::paramFanOutCount()
140{
141 ASSERT(context().isGraphOwner());
142 return m_params.size();
143}
144
145unsigned AudioNodeOutput::renderingFanOutCount() const
146{
147 return m_renderingFanOutCount;
148}
149
150unsigned AudioNodeOutput::renderingParamFanOutCount() const
151{
152 return m_renderingParamFanOutCount;
153}
154
155void AudioNodeOutput::addInput(AudioNodeInput* input)
156{
157 ASSERT(context().isGraphOwner());
158
159 ASSERT(input);
160 if (!input)
161 return;
162
163 m_inputs.add(input);
164}
165
166void AudioNodeOutput::removeInput(AudioNodeInput* input)
167{
168 ASSERT(context().isGraphOwner());
169
170 ASSERT(input);
171 if (!input)
172 return;
173
174 m_inputs.remove(input);
175}
176
177void AudioNodeOutput::disconnectAllInputs()
178{
179 ASSERT(context().isGraphOwner());
180
181 // AudioNodeInput::disconnect() changes m_inputs by calling removeInput().
182 while (!m_inputs.isEmpty()) {
183 AudioNodeInput* input = *m_inputs.begin();
184 input->disconnect(this);
185 }
186}
187
188void AudioNodeOutput::addParam(AudioParam* param)
189{
190 ASSERT(context().isGraphOwner());
191
192 ASSERT(param);
193 if (!param)
194 return;
195
196 m_params.add(param);
197}
198
199void AudioNodeOutput::removeParam(AudioParam* param)
200{
201 ASSERT(context().isGraphOwner());
202
203 ASSERT(param);
204 if (!param)
205 return;
206
207 m_params.remove(param);
208}
209
210void AudioNodeOutput::disconnectAllParams()
211{
212 ASSERT(context().isGraphOwner());
213
214 // AudioParam::disconnect() changes m_params by calling removeParam().
215 while (!m_params.isEmpty()) {
216 AudioParam* param = m_params.begin()->get();
217 param->disconnect(this);
218 }
219}
220
221void AudioNodeOutput::disconnectAll()
222{
223 disconnectAllInputs();
224 disconnectAllParams();
225}
226
227void AudioNodeOutput::disable()
228{
229 ASSERT(context().isGraphOwner());
230
231 if (m_isEnabled) {
232 for (auto& input : m_inputs)
233 input->disable(this);
234 m_isEnabled = false;
235 }
236}
237
238void AudioNodeOutput::enable()
239{
240 ASSERT(context().isGraphOwner());
241
242 if (!m_isEnabled) {
243 for (auto& input : m_inputs)
244 input->enable(this);
245 m_isEnabled = true;
246 }
247}
248
249} // namespace WebCore
250
251#endif // ENABLE(WEB_AUDIO)
252