michael@0: /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
michael@0: /* vim:set ts=2 sw=2 sts=2 et cindent: */
michael@0: /* This Source Code Form is subject to the terms of the Mozilla Public
michael@0:  * License, v. 2.0. If a copy of the MPL was not distributed with this
michael@0:  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
michael@0: 
michael@0: #include "GainNode.h"
michael@0: #include "mozilla/dom/GainNodeBinding.h"
michael@0: #include "AudioNodeEngine.h"
michael@0: #include "AudioNodeStream.h"
michael@0: #include "AudioDestinationNode.h"
michael@0: #include "WebAudioUtils.h"
michael@0: 
michael@0: namespace mozilla {
michael@0: namespace dom {
michael@0: 
michael@0: NS_IMPL_CYCLE_COLLECTION_INHERITED(GainNode, AudioNode,
michael@0:                                    mGain)
michael@0: 
michael@0: NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION_INHERITED(GainNode)
michael@0: NS_INTERFACE_MAP_END_INHERITING(AudioNode)
michael@0: 
michael@0: NS_IMPL_ADDREF_INHERITED(GainNode, AudioNode)
michael@0: NS_IMPL_RELEASE_INHERITED(GainNode, AudioNode)
michael@0: 
michael@0: class GainNodeEngine : public AudioNodeEngine
michael@0: {
michael@0: public:
michael@0:   GainNodeEngine(AudioNode* aNode, AudioDestinationNode* aDestination)
michael@0:     : AudioNodeEngine(aNode)
michael@0:     , mSource(nullptr)
michael@0:     , mDestination(static_cast<AudioNodeStream*> (aDestination->Stream()))
michael@0:     // Keep the default value in sync with the default value in GainNode::GainNode.
michael@0:     , mGain(1.f)
michael@0:   {
michael@0:   }
michael@0: 
michael@0:   void SetSourceStream(AudioNodeStream* aSource)
michael@0:   {
michael@0:     mSource = aSource;
michael@0:   }
michael@0: 
michael@0:   enum Parameters {
michael@0:     GAIN
michael@0:   };
michael@0:   void SetTimelineParameter(uint32_t aIndex,
michael@0:                             const AudioParamTimeline& aValue,
michael@0:                             TrackRate aSampleRate) MOZ_OVERRIDE
michael@0:   {
michael@0:     switch (aIndex) {
michael@0:     case GAIN:
michael@0:       MOZ_ASSERT(mSource && mDestination);
michael@0:       mGain = aValue;
michael@0:       WebAudioUtils::ConvertAudioParamToTicks(mGain, mSource, mDestination);
michael@0:       break;
michael@0:     default:
michael@0:       NS_ERROR("Bad GainNodeEngine TimelineParameter");
michael@0:     }
michael@0:   }
michael@0: 
michael@0:   virtual void ProcessBlock(AudioNodeStream* aStream,
michael@0:                             const AudioChunk& aInput,
michael@0:                             AudioChunk* aOutput,
michael@0:                             bool* aFinished)
michael@0:   {
michael@0:     MOZ_ASSERT(mSource == aStream, "Invalid source stream");
michael@0: 
michael@0:     if (aInput.IsNull()) {
michael@0:       // If input is silent, so is the output
michael@0:       aOutput->SetNull(WEBAUDIO_BLOCK_SIZE);
michael@0:     } else if (mGain.HasSimpleValue()) {
michael@0:       // Optimize the case where we only have a single value set as the volume
michael@0:       float gain = mGain.GetValue();
michael@0:       if (gain == 0.0f) {
michael@0:         aOutput->SetNull(WEBAUDIO_BLOCK_SIZE);
michael@0:       } else {
michael@0:         *aOutput = aInput;
michael@0:         aOutput->mVolume *= gain;
michael@0:       }
michael@0:     } else {
michael@0:       // First, compute a vector of gains for each track tick based on the
michael@0:       // timeline at hand, and then for each channel, multiply the values
michael@0:       // in the buffer with the gain vector.
michael@0:       AllocateAudioBlock(aInput.mChannelData.Length(), aOutput);
michael@0: 
michael@0:       // Compute the gain values for the duration of the input AudioChunk
michael@0:       // XXX we need to add a method to AudioEventTimeline to compute this buffer directly.
michael@0:       float computedGain[WEBAUDIO_BLOCK_SIZE];
michael@0:       for (size_t counter = 0; counter < WEBAUDIO_BLOCK_SIZE; ++counter) {
michael@0:         TrackTicks tick = aStream->GetCurrentPosition();
michael@0:         computedGain[counter] = mGain.GetValueAtTime(tick, counter) * aInput.mVolume;
michael@0:       }
michael@0: 
michael@0:       // Apply the gain to the output buffer
michael@0:       for (size_t channel = 0; channel < aOutput->mChannelData.Length(); ++channel) {
michael@0:         const float* inputBuffer = static_cast<const float*> (aInput.mChannelData[channel]);
michael@0:         float* buffer = static_cast<float*> (const_cast<void*>
michael@0:                           (aOutput->mChannelData[channel]));
michael@0:         AudioBlockCopyChannelWithScale(inputBuffer, computedGain, buffer);
michael@0:       }
michael@0:     }
michael@0:   }
michael@0: 
michael@0:   virtual size_t SizeOfExcludingThis(MallocSizeOf aMallocSizeOf) const MOZ_OVERRIDE
michael@0:   {
michael@0:     // Not owned:
michael@0:     // - mSource (probably)
michael@0:     // - mDestination (probably)
michael@0:     // - mGain - Internal ref owned by AudioNode
michael@0:     return AudioNodeEngine::SizeOfExcludingThis(aMallocSizeOf);
michael@0:   }
michael@0: 
michael@0:   virtual size_t SizeOfIncludingThis(MallocSizeOf aMallocSizeOf) const MOZ_OVERRIDE
michael@0:   {
michael@0:     return aMallocSizeOf(this) + SizeOfExcludingThis(aMallocSizeOf);
michael@0:   }
michael@0: 
michael@0:   AudioNodeStream* mSource;
michael@0:   AudioNodeStream* mDestination;
michael@0:   AudioParamTimeline mGain;
michael@0: };
michael@0: 
michael@0: GainNode::GainNode(AudioContext* aContext)
michael@0:   : AudioNode(aContext,
michael@0:               2,
michael@0:               ChannelCountMode::Max,
michael@0:               ChannelInterpretation::Speakers)
michael@0:   , mGain(new AudioParam(MOZ_THIS_IN_INITIALIZER_LIST(),
michael@0:                          SendGainToStream, 1.0f))
michael@0: {
michael@0:   GainNodeEngine* engine = new GainNodeEngine(this, aContext->Destination());
michael@0:   mStream = aContext->Graph()->CreateAudioNodeStream(engine, MediaStreamGraph::INTERNAL_STREAM);
michael@0:   engine->SetSourceStream(static_cast<AudioNodeStream*> (mStream.get()));
michael@0: }
michael@0: 
michael@0: size_t
michael@0: GainNode::SizeOfExcludingThis(MallocSizeOf aMallocSizeOf) const
michael@0: {
michael@0:   size_t amount = AudioNode::SizeOfExcludingThis(aMallocSizeOf);
michael@0:   amount += mGain->SizeOfIncludingThis(aMallocSizeOf);
michael@0:   return amount;
michael@0: }
michael@0: 
michael@0: size_t
michael@0: GainNode::SizeOfIncludingThis(MallocSizeOf aMallocSizeOf) const
michael@0: {
michael@0:   return aMallocSizeOf(this) + SizeOfExcludingThis(aMallocSizeOf);
michael@0: }
michael@0: 
michael@0: JSObject*
michael@0: GainNode::WrapObject(JSContext* aCx)
michael@0: {
michael@0:   return GainNodeBinding::Wrap(aCx, this);
michael@0: }
michael@0: 
michael@0: void
michael@0: GainNode::SendGainToStream(AudioNode* aNode)
michael@0: {
michael@0:   GainNode* This = static_cast<GainNode*>(aNode);
michael@0:   SendTimelineParameterToStream(This, GainNodeEngine::GAIN, *This->mGain);
michael@0: }
michael@0: 
michael@0: }
michael@0: }
michael@0: