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/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim:set ts=2 sw=2 sts=2 et cindent: */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
#include "StereoPannerNode.h"
#include "mozilla/dom/StereoPannerNodeBinding.h"
#include "AudioNodeEngine.h"
#include "AudioNodeTrack.h"
#include "AudioDestinationNode.h"
#include "AlignmentUtils.h"
#include "WebAudioUtils.h"
#include "PanningUtils.h"
#include "AudioParamTimeline.h"
#include "AudioParam.h"
#include "Tracing.h"
namespace mozilla::dom {
NS_IMPL_CYCLE_COLLECTION_INHERITED(StereoPannerNode, AudioNode, mPan)
NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(StereoPannerNode)
NS_INTERFACE_MAP_END_INHERITING(AudioNode)
NS_IMPL_ADDREF_INHERITED(StereoPannerNode, AudioNode)
NS_IMPL_RELEASE_INHERITED(StereoPannerNode, AudioNode)
class StereoPannerNodeEngine final : public AudioNodeEngine {
public:
StereoPannerNodeEngine(AudioNode* aNode, AudioDestinationNode* aDestination)
: AudioNodeEngine(aNode),
mDestination(aDestination->Track())
// Keep the default value in sync with the default value in
// StereoPannerNode::StereoPannerNode.
,
mPan(0.f) {}
enum Parameters { PAN };
void RecvTimelineEvent(uint32_t aIndex, AudioParamEvent& aEvent) override {
MOZ_ASSERT(mDestination);
aEvent.ConvertToTicks(mDestination);
switch (aIndex) {
case PAN:
mPan.InsertEvent<int64_t>(aEvent);
break;
default:
NS_ERROR("Bad StereoPannerNode TimelineParameter");
}
}
void GetGainValuesForPanning(float aPanning, bool aMonoToStereo,
float& aLeftGain, float& aRightGain) {
// Clamp and normalize the panning in [0; 1]
aPanning = std::min(std::max(aPanning, -1.f), 1.f);
if (aMonoToStereo) {
aPanning += 1;
aPanning /= 2;
} else if (aPanning <= 0) {
aPanning += 1;
}
aLeftGain = fdlibm_cos(0.5 * M_PI * aPanning);
aRightGain = fdlibm_sin(0.5 * M_PI * aPanning);
}
void SetToSilentStereoBlock(AudioBlock* aChunk) {
for (uint32_t channel = 0; channel < 2; channel++) {
float* samples = aChunk->ChannelFloatsForWrite(channel);
for (uint32_t i = 0; i < WEBAUDIO_BLOCK_SIZE; i++) {
samples[i] = 0.f;
}
}
}
void UpmixToStereoIfNeeded(const AudioBlock& aInput, AudioBlock* aOutput) {
if (aInput.ChannelCount() == 2) {
*aOutput = aInput;
} else {
MOZ_ASSERT(aInput.ChannelCount() == 1);
aOutput->SetBuffer(aInput.GetBuffer());
aOutput->mChannelData.SetLength(2);
for (uint32_t i = 0; i < 2; ++i) {
aOutput->mChannelData[i] = aInput.ChannelData<float>()[0];
}
// 1/sqrt(2) multiplier is because StereoPanner up-mixing differs from
// input up-mixing.
aOutput->mVolume = M_SQRT1_2 * aInput.mVolume;
aOutput->mBufferFormat = AUDIO_FORMAT_FLOAT32;
}
}
virtual void ProcessBlock(AudioNodeTrack* aTrack, GraphTime aFrom,
const AudioBlock& aInput, AudioBlock* aOutput,
bool* aFinished) override {
// The output of this node is always stereo, no matter what the inputs are.
MOZ_ASSERT(aInput.ChannelCount() <= 2);
TRACE("StereoPannerNodeEngine::ProcessBlock");
bool monoToStereo = aInput.ChannelCount() == 1;
if (aInput.IsNull()) {
// If input is silent, so is the output
aOutput->SetNull(WEBAUDIO_BLOCK_SIZE);
} else if (mPan.HasSimpleValue()) {
float panning = mPan.GetValue();
// If the panning is 0.0, we can simply copy the input to the
// output with gain applied, up-mixing to stereo if needed.
if (panning == 0.0f) {
UpmixToStereoIfNeeded(aInput, aOutput);
} else {
// Optimize the case where the panning is constant for this processing
// block: we can just apply a constant gain on the left and right
// channel
float gainL, gainR;
GetGainValuesForPanning(panning, monoToStereo, gainL, gainR);
ApplyStereoPanning(aInput, aOutput, gainL, gainR, panning <= 0);
}
} else {
float computedGain[2 * WEBAUDIO_BLOCK_SIZE + 4];
bool onLeft[WEBAUDIO_BLOCK_SIZE];
float values[WEBAUDIO_BLOCK_SIZE];
TrackTime tick = mDestination->GraphTimeToTrackTime(aFrom);
mPan.GetValuesAtTime(tick, values, WEBAUDIO_BLOCK_SIZE);
float* alignedComputedGain = ALIGNED16(computedGain);
ASSERT_ALIGNED16(alignedComputedGain);
for (size_t counter = 0; counter < WEBAUDIO_BLOCK_SIZE; ++counter) {
float left, right;
GetGainValuesForPanning(values[counter], monoToStereo, left, right);
alignedComputedGain[counter] = left;
alignedComputedGain[WEBAUDIO_BLOCK_SIZE + counter] = right;
onLeft[counter] = values[counter] <= 0;
}
// Apply the gain to the output buffer
ApplyStereoPanning(aInput, aOutput, alignedComputedGain,
&alignedComputedGain[WEBAUDIO_BLOCK_SIZE], onLeft);
}
}
virtual size_t SizeOfIncludingThis(
MallocSizeOf aMallocSizeOf) const override {
return aMallocSizeOf(this) + SizeOfExcludingThis(aMallocSizeOf);
}
RefPtr<AudioNodeTrack> mDestination;
AudioParamTimeline mPan;
};
StereoPannerNode::StereoPannerNode(AudioContext* aContext)
: AudioNode(aContext, 2, ChannelCountMode::Clamped_max,
ChannelInterpretation::Speakers) {
mPan =
CreateAudioParam(StereoPannerNodeEngine::PAN, u"pan"_ns, 0.f, -1.f, 1.f);
StereoPannerNodeEngine* engine =
new StereoPannerNodeEngine(this, aContext->Destination());
mTrack = AudioNodeTrack::Create(
aContext, engine, AudioNodeTrack::NO_TRACK_FLAGS, aContext->Graph());
}
/* static */
already_AddRefed<StereoPannerNode> StereoPannerNode::Create(
AudioContext& aAudioContext, const StereoPannerOptions& aOptions,
ErrorResult& aRv) {
RefPtr<StereoPannerNode> audioNode = new StereoPannerNode(&aAudioContext);
audioNode->Initialize(aOptions, aRv);
if (NS_WARN_IF(aRv.Failed())) {
return nullptr;
}
audioNode->Pan()->SetInitialValue(aOptions.mPan);
return audioNode.forget();
}
size_t StereoPannerNode::SizeOfExcludingThis(MallocSizeOf aMallocSizeOf) const {
size_t amount = AudioNode::SizeOfExcludingThis(aMallocSizeOf);
amount += mPan->SizeOfIncludingThis(aMallocSizeOf);
return amount;
}
size_t StereoPannerNode::SizeOfIncludingThis(MallocSizeOf aMallocSizeOf) const {
return aMallocSizeOf(this) + SizeOfExcludingThis(aMallocSizeOf);
}
JSObject* StereoPannerNode::WrapObject(JSContext* aCx,
JS::Handle<JSObject*> aGivenProto) {
return StereoPannerNode_Binding::Wrap(aCx, this, aGivenProto);
}
} // namespace mozilla::dom