1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/content/media/webaudio/AudioNode.h Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,274 @@
1.4 +/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
1.5 +/* vim:set ts=2 sw=2 sts=2 et cindent: */
1.6 +/* This Source Code Form is subject to the terms of the Mozilla Public
1.7 + * License, v. 2.0. If a copy of the MPL was not distributed with this
1.8 + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
1.9 +
1.10 +#ifndef AudioNode_h_
1.11 +#define AudioNode_h_
1.12 +
1.13 +#include "mozilla/DOMEventTargetHelper.h"
1.14 +#include "mozilla/dom/AudioNodeBinding.h"
1.15 +#include "nsCycleCollectionParticipant.h"
1.16 +#include "nsAutoPtr.h"
1.17 +#include "nsTArray.h"
1.18 +#include "AudioContext.h"
1.19 +#include "MediaStreamGraph.h"
1.20 +#include "WebAudioUtils.h"
1.21 +#include "mozilla/MemoryReporting.h"
1.22 +
1.23 +namespace mozilla {
1.24 +
1.25 +namespace dom {
1.26 +
1.27 +class AudioContext;
1.28 +class AudioBufferSourceNode;
1.29 +class AudioParam;
1.30 +class AudioParamTimeline;
1.31 +struct ThreeDPoint;
1.32 +
1.33 +template<class T>
1.34 +class SelfReference {
1.35 +public:
1.36 + SelfReference() : mHeld(false) {}
1.37 + ~SelfReference()
1.38 + {
1.39 + NS_ASSERTION(!mHeld, "Forgot to drop the self reference?");
1.40 + }
1.41 +
1.42 + void Take(T* t)
1.43 + {
1.44 + if (!mHeld) {
1.45 + mHeld = true;
1.46 + t->AddRef();
1.47 + }
1.48 + }
1.49 + void Drop(T* t)
1.50 + {
1.51 + if (mHeld) {
1.52 + mHeld = false;
1.53 + t->Release();
1.54 + }
1.55 + }
1.56 +
1.57 + operator bool() const { return mHeld; }
1.58 +
1.59 +private:
1.60 + bool mHeld;
1.61 +};
1.62 +
1.63 +/**
1.64 + * The DOM object representing a Web Audio AudioNode.
1.65 + *
1.66 + * Each AudioNode has a MediaStream representing the actual
1.67 + * real-time processing and output of this AudioNode.
1.68 + *
1.69 + * We track the incoming and outgoing connections to other AudioNodes.
1.70 + * Outgoing connections have strong ownership. Also, AudioNodes that will
1.71 + * produce sound on their output even when they have silent or no input ask
1.72 + * the AudioContext to keep playing or tail-time references to keep them alive
1.73 + * until the context is finished.
1.74 + *
1.75 + * Explicit disconnections will only remove references from output nodes after
1.76 + * the graph is notified and the main thread receives a reply. Similarly,
1.77 + * nodes with playing or tail-time references release these references only
1.78 + * after receiving notification from their engine on the graph thread that
1.79 + * playing has stopped. Engines notifying the main thread that they have
1.80 + * finished do so strictly *after* producing and returning their last block.
1.81 + * In this way, an engine that receives non-null input knows that the input
1.82 + * comes from nodes that are still alive and will keep their output nodes
1.83 + * alive for at least as long as it takes to process messages from the graph
1.84 + * thread. i.e. the engine receiving non-null input knows that its node is
1.85 + * still alive, and will still be alive when it receives a message from the
1.86 + * engine.
1.87 + */
1.88 +class AudioNode : public DOMEventTargetHelper
1.89 +{
1.90 +protected:
1.91 + // You can only use refcounting to delete this object
1.92 + virtual ~AudioNode();
1.93 +
1.94 +public:
1.95 + AudioNode(AudioContext* aContext,
1.96 + uint32_t aChannelCount,
1.97 + ChannelCountMode aChannelCountMode,
1.98 + ChannelInterpretation aChannelInterpretation);
1.99 +
1.100 + // This should be idempotent (safe to call multiple times).
1.101 + virtual void DestroyMediaStream();
1.102 +
1.103 + NS_DECL_ISUPPORTS_INHERITED
1.104 + NS_DECL_CYCLE_COLLECTION_CLASS_INHERITED(AudioNode,
1.105 + DOMEventTargetHelper)
1.106 +
1.107 + virtual AudioBufferSourceNode* AsAudioBufferSourceNode() {
1.108 + return nullptr;
1.109 + }
1.110 +
1.111 + virtual const DelayNode* AsDelayNode() const {
1.112 + return nullptr;
1.113 + }
1.114 +
1.115 + AudioContext* GetParentObject() const
1.116 + {
1.117 + return mContext;
1.118 + }
1.119 +
1.120 + AudioContext* Context() const
1.121 + {
1.122 + return mContext;
1.123 + }
1.124 +
1.125 + virtual void Connect(AudioNode& aDestination, uint32_t aOutput,
1.126 + uint32_t aInput, ErrorResult& aRv);
1.127 +
1.128 + virtual void Connect(AudioParam& aDestination, uint32_t aOutput,
1.129 + ErrorResult& aRv);
1.130 +
1.131 + virtual void Disconnect(uint32_t aOutput, ErrorResult& aRv);
1.132 +
1.133 + // The following two virtual methods must be implemented by each node type
1.134 + // to provide their number of input and output ports. These numbers are
1.135 + // constant for the lifetime of the node. Both default to 1.
1.136 + virtual uint16_t NumberOfInputs() const { return 1; }
1.137 + virtual uint16_t NumberOfOutputs() const { return 1; }
1.138 +
1.139 + uint32_t ChannelCount() const { return mChannelCount; }
1.140 + virtual void SetChannelCount(uint32_t aChannelCount, ErrorResult& aRv)
1.141 + {
1.142 + if (aChannelCount == 0 ||
1.143 + aChannelCount > WebAudioUtils::MaxChannelCount) {
1.144 + aRv.Throw(NS_ERROR_DOM_NOT_SUPPORTED_ERR);
1.145 + return;
1.146 + }
1.147 + mChannelCount = aChannelCount;
1.148 + SendChannelMixingParametersToStream();
1.149 + }
1.150 + ChannelCountMode ChannelCountModeValue() const
1.151 + {
1.152 + return mChannelCountMode;
1.153 + }
1.154 + virtual void SetChannelCountModeValue(ChannelCountMode aMode, ErrorResult& aRv)
1.155 + {
1.156 + mChannelCountMode = aMode;
1.157 + SendChannelMixingParametersToStream();
1.158 + }
1.159 + ChannelInterpretation ChannelInterpretationValue() const
1.160 + {
1.161 + return mChannelInterpretation;
1.162 + }
1.163 + void SetChannelInterpretationValue(ChannelInterpretation aMode)
1.164 + {
1.165 + mChannelInterpretation = aMode;
1.166 + SendChannelMixingParametersToStream();
1.167 + }
1.168 +
1.169 + struct InputNode {
1.170 + ~InputNode()
1.171 + {
1.172 + if (mStreamPort) {
1.173 + mStreamPort->Destroy();
1.174 + }
1.175 + }
1.176 +
1.177 + size_t SizeOfExcludingThis(MallocSizeOf aMallocSizeOf) const
1.178 + {
1.179 + size_t amount = 0;
1.180 + if (mStreamPort) {
1.181 + amount += mStreamPort->SizeOfIncludingThis(aMallocSizeOf);
1.182 + }
1.183 +
1.184 + return amount;
1.185 + }
1.186 +
1.187 + // Weak reference.
1.188 + AudioNode* mInputNode;
1.189 + nsRefPtr<MediaInputPort> mStreamPort;
1.190 + // The index of the input port this node feeds into.
1.191 + // This is not used for connections to AudioParams.
1.192 + uint32_t mInputPort;
1.193 + // The index of the output port this node comes out of.
1.194 + uint32_t mOutputPort;
1.195 + };
1.196 +
1.197 + MediaStream* Stream() { return mStream; }
1.198 +
1.199 + const nsTArray<InputNode>& InputNodes() const
1.200 + {
1.201 + return mInputNodes;
1.202 + }
1.203 + const nsTArray<nsRefPtr<AudioNode> >& OutputNodes() const
1.204 + {
1.205 + return mOutputNodes;
1.206 + }
1.207 + const nsTArray<nsRefPtr<AudioParam> >& OutputParams() const
1.208 + {
1.209 + return mOutputParams;
1.210 + }
1.211 +
1.212 + void RemoveOutputParam(AudioParam* aParam);
1.213 +
1.214 + // MarkActive() asks the context to keep the AudioNode alive until the
1.215 + // context is finished. This takes care of "playing" references and
1.216 + // "tail-time" references.
1.217 + void MarkActive() { Context()->RegisterActiveNode(this); }
1.218 + // Active nodes call MarkInactive() when they have finished producing sound
1.219 + // for the foreseeable future.
1.220 + // Do not call MarkInactive from a node destructor. If the destructor is
1.221 + // called, then the node is already inactive.
1.222 + // MarkInactive() may delete |this|.
1.223 + void MarkInactive() { Context()->UnregisterActiveNode(this); }
1.224 +
1.225 + virtual size_t SizeOfExcludingThis(MallocSizeOf aMallocSizeOf) const;
1.226 + virtual size_t SizeOfIncludingThis(MallocSizeOf aMallocSizeOf) const;
1.227 +
1.228 + virtual const char* NodeType() const = 0;
1.229 +
1.230 +private:
1.231 + friend class AudioBufferSourceNode;
1.232 + // This could possibly delete 'this'.
1.233 + void DisconnectFromGraph();
1.234 +
1.235 +protected:
1.236 + static void Callback(AudioNode* aNode) { /* not implemented */ }
1.237 +
1.238 + // Helpers for sending different value types to streams
1.239 + void SendDoubleParameterToStream(uint32_t aIndex, double aValue);
1.240 + void SendInt32ParameterToStream(uint32_t aIndex, int32_t aValue);
1.241 + void SendThreeDPointParameterToStream(uint32_t aIndex, const ThreeDPoint& aValue);
1.242 + void SendChannelMixingParametersToStream();
1.243 + static void SendTimelineParameterToStream(AudioNode* aNode, uint32_t aIndex,
1.244 + const AudioParamTimeline& aValue);
1.245 +
1.246 +private:
1.247 + nsRefPtr<AudioContext> mContext;
1.248 +
1.249 +protected:
1.250 + // Must be set in the constructor. Must not be null.
1.251 + // If MaxNumberOfInputs() is > 0, then mStream must be a ProcessedMediaStream.
1.252 + nsRefPtr<MediaStream> mStream;
1.253 +
1.254 +private:
1.255 + // For every InputNode, there is a corresponding entry in mOutputNodes of the
1.256 + // InputNode's mInputNode.
1.257 + nsTArray<InputNode> mInputNodes;
1.258 + // For every mOutputNode entry, there is a corresponding entry in mInputNodes
1.259 + // of the mOutputNode entry. We won't necessarily be able to identify the
1.260 + // exact matching entry, since mOutputNodes doesn't include the port
1.261 + // identifiers and the same node could be connected on multiple ports.
1.262 + nsTArray<nsRefPtr<AudioNode> > mOutputNodes;
1.263 + // For every mOutputParams entry, there is a corresponding entry in
1.264 + // AudioParam::mInputNodes of the mOutputParams entry. We won't necessarily be
1.265 + // able to identify the exact matching entry, since mOutputParams doesn't
1.266 + // include the port identifiers and the same node could be connected on
1.267 + // multiple ports.
1.268 + nsTArray<nsRefPtr<AudioParam> > mOutputParams;
1.269 + uint32_t mChannelCount;
1.270 + ChannelCountMode mChannelCountMode;
1.271 + ChannelInterpretation mChannelInterpretation;
1.272 +};
1.273 +
1.274 +}
1.275 +}
1.276 +
1.277 +#endif
