1 /* 2 * Copyright (C) 2012, Intel Corporation. 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 "modules/webaudio/AudioBasicInspectorNode.h" 30 31 #include "modules/webaudio/AudioContext.h" 32 #include "modules/webaudio/AudioNodeInput.h" 33 #include "modules/webaudio/AudioNodeOutput.h" 34 35 namespace WebCore { 36 37 AudioBasicInspectorNode::AudioBasicInspectorNode(AudioContext* context, float sampleRate, unsigned outputChannelCount) 38 : AudioNode(context, sampleRate) 39 , m_needAutomaticPull(false) 40 { 41 addInput(adoptPtr(new AudioNodeInput(this))); 42 addOutput(adoptPtr(new AudioNodeOutput(this, outputChannelCount))); 43 } 44 45 // We override pullInputs() as an optimization allowing this node to take advantage of in-place processing, 46 // where the input is simply passed through unprocessed to the output. 47 // Note: this only applies if the input and output channel counts match. 48 void AudioBasicInspectorNode::pullInputs(size_t framesToProcess) 49 { 50 // Render input stream - try to render directly into output bus for pass-through processing where process() doesn't need to do anything... 51 input(0)->pull(output(0)->bus(), framesToProcess); 52 } 53 54 void AudioBasicInspectorNode::connect(AudioNode* destination, unsigned outputIndex, unsigned inputIndex, ExceptionState& exceptionState) 55 { 56 ASSERT(isMainThread()); 57 58 AudioContext::AutoLocker locker(context()); 59 60 AudioNode::connect(destination, outputIndex, inputIndex, exceptionState); 61 updatePullStatus(); 62 } 63 64 void AudioBasicInspectorNode::disconnect(unsigned outputIndex, ExceptionState& exceptionState) 65 { 66 ASSERT(isMainThread()); 67 68 AudioContext::AutoLocker locker(context()); 69 70 AudioNode::disconnect(outputIndex, exceptionState); 71 updatePullStatus(); 72 } 73 74 void AudioBasicInspectorNode::checkNumberOfChannelsForInput(AudioNodeInput* input) 75 { 76 ASSERT(context()->isAudioThread() && context()->isGraphOwner()); 77 78 ASSERT(input == this->input(0)); 79 if (input != this->input(0)) 80 return; 81 82 unsigned numberOfChannels = input->numberOfChannels(); 83 84 if (numberOfChannels != output(0)->numberOfChannels()) { 85 // This will propagate the channel count to any nodes connected further downstream in the graph. 86 output(0)->setNumberOfChannels(numberOfChannels); 87 } 88 89 AudioNode::checkNumberOfChannelsForInput(input); 90 91 updatePullStatus(); 92 } 93 94 void AudioBasicInspectorNode::updatePullStatus() 95 { 96 ASSERT(context()->isGraphOwner()); 97 98 if (output(0)->isConnected()) { 99 // When an AudioBasicInspectorNode is connected to a downstream node, it will get pulled by the 100 // downstream node, thus remove it from the context's automatic pull list. 101 if (m_needAutomaticPull) { 102 context()->removeAutomaticPullNode(this); 103 m_needAutomaticPull = false; 104 } 105 } else { 106 unsigned numberOfInputConnections = input(0)->numberOfRenderingConnections(); 107 if (numberOfInputConnections && !m_needAutomaticPull) { 108 // When an AudioBasicInspectorNode is not connected to any downstream node while still connected from 109 // upstream node(s), add it to the context's automatic pull list. 110 context()->addAutomaticPullNode(this); 111 m_needAutomaticPull = true; 112 } else if (!numberOfInputConnections && m_needAutomaticPull) { 113 // The AudioBasicInspectorNode is connected to nothing, remove it from the context's automatic pull list. 114 context()->removeAutomaticPullNode(this); 115 m_needAutomaticPull = false; 116 } 117 } 118 } 119 120 } // namespace WebCore 121 122 #endif // ENABLE(WEB_AUDIO) 123