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gecko-dev/dom/media/webaudio/PannerNode.cpp

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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
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#include "PannerNode.h"
#include "AlignmentUtils.h"
#include "AudioDestinationNode.h"
#include "AudioNodeEngine.h"
#include "AudioNodeStream.h"
#include "AudioListener.h"
#include "PanningUtils.h"
#include "AudioBufferSourceNode.h"
#include "PlayingRefChangeHandler.h"
#include "blink/HRTFPanner.h"
#include "blink/HRTFDatabaseLoader.h"
#include "nsAutoPtr.h"
using WebCore::HRTFDatabaseLoader;
using WebCore::HRTFPanner;
namespace mozilla {
namespace dom {
using namespace std;
NS_IMPL_CYCLE_COLLECTION_CLASS(PannerNode)
NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN_INHERITED(PannerNode, AudioNode)
NS_IMPL_CYCLE_COLLECTION_UNLINK(mPositionX, mPositionY, mPositionZ,
mOrientationX, mOrientationY, mOrientationZ)
NS_IMPL_CYCLE_COLLECTION_UNLINK_END
NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN_INHERITED(PannerNode, AudioNode)
NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mPositionX, mPositionY, mPositionZ,
mOrientationX, mOrientationY, mOrientationZ)
NS_IMPL_CYCLE_COLLECTION_TRAVERSE_END
NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(PannerNode)
NS_INTERFACE_MAP_END_INHERITING(AudioNode)
NS_IMPL_ADDREF_INHERITED(PannerNode, AudioNode)
NS_IMPL_RELEASE_INHERITED(PannerNode, AudioNode)
class PannerNodeEngine final : public AudioNodeEngine {
public:
explicit PannerNodeEngine(AudioNode* aNode,
AudioDestinationNode* aDestination,
AudioListenerEngine* aListenerEngine)
: AudioNodeEngine(aNode),
mDestination(aDestination->Stream()),
mListenerEngine(aListenerEngine)
// Please keep these default values consistent with
// PannerNode::PannerNode below.
,
mPanningModelFunction(&PannerNodeEngine::EqualPowerPanningFunction),
mDistanceModelFunction(&PannerNodeEngine::InverseGainFunction),
mPositionX(0.),
mPositionY(0.),
mPositionZ(0.),
mOrientationX(1.),
mOrientationY(0.),
mOrientationZ(0.),
mRefDistance(1.),
mMaxDistance(10000.),
mRolloffFactor(1.),
mConeInnerAngle(360.),
mConeOuterAngle(360.),
mConeOuterGain(0.),
mLeftOverData(INT_MIN) {}
void RecvTimelineEvent(uint32_t aIndex, AudioTimelineEvent& aEvent) override {
MOZ_ASSERT(mDestination);
WebAudioUtils::ConvertAudioTimelineEventToTicks(aEvent, mDestination);
switch (aIndex) {
case PannerNode::POSITIONX:
mPositionX.InsertEvent<int64_t>(aEvent);
break;
case PannerNode::POSITIONY:
mPositionY.InsertEvent<int64_t>(aEvent);
break;
case PannerNode::POSITIONZ:
mPositionZ.InsertEvent<int64_t>(aEvent);
break;
case PannerNode::ORIENTATIONX:
mOrientationX.InsertEvent<int64_t>(aEvent);
break;
case PannerNode::ORIENTATIONY:
mOrientationY.InsertEvent<int64_t>(aEvent);
break;
case PannerNode::ORIENTATIONZ:
mOrientationZ.InsertEvent<int64_t>(aEvent);
break;
default:
NS_ERROR("Bad PannerNode TimelineParameter");
}
}
void CreateHRTFPanner() {
MOZ_ASSERT(NS_IsMainThread());
if (mHRTFPanner) {
return;
}
// HRTFDatabaseLoader needs to be fetched on the main thread.
RefPtr<HRTFDatabaseLoader> loader =
HRTFDatabaseLoader::createAndLoadAsynchronouslyIfNecessary(
NodeMainThread()->Context()->SampleRate());
mHRTFPanner = new HRTFPanner(NodeMainThread()->Context()->SampleRate(),
loader.forget());
}
void SetInt32Parameter(uint32_t aIndex, int32_t aParam) override {
switch (aIndex) {
case PannerNode::PANNING_MODEL:
switch (PanningModelType(aParam)) {
case PanningModelType::Equalpower:
mPanningModelFunction =
&PannerNodeEngine::EqualPowerPanningFunction;
break;
case PanningModelType::HRTF:
mPanningModelFunction = &PannerNodeEngine::HRTFPanningFunction;
break;
default:
MOZ_ASSERT_UNREACHABLE("We should never see alternate names here");
break;
}
break;
case PannerNode::DISTANCE_MODEL:
switch (DistanceModelType(aParam)) {
case DistanceModelType::Inverse:
mDistanceModelFunction = &PannerNodeEngine::InverseGainFunction;
break;
case DistanceModelType::Linear:
mDistanceModelFunction = &PannerNodeEngine::LinearGainFunction;
break;
case DistanceModelType::Exponential:
mDistanceModelFunction = &PannerNodeEngine::ExponentialGainFunction;
break;
default:
MOZ_ASSERT_UNREACHABLE("We should never see alternate names here");
break;
}
break;
default:
NS_ERROR("Bad PannerNodeEngine Int32Parameter");
}
}
void SetDoubleParameter(uint32_t aIndex, double aParam) override {
switch (aIndex) {
case PannerNode::REF_DISTANCE:
mRefDistance = aParam;
break;
case PannerNode::MAX_DISTANCE:
mMaxDistance = aParam;
break;
case PannerNode::ROLLOFF_FACTOR:
mRolloffFactor = aParam;
break;
case PannerNode::CONE_INNER_ANGLE:
mConeInnerAngle = aParam;
break;
case PannerNode::CONE_OUTER_ANGLE:
mConeOuterAngle = aParam;
break;
case PannerNode::CONE_OUTER_GAIN:
mConeOuterGain = aParam;
break;
default:
NS_ERROR("Bad PannerNodeEngine DoubleParameter");
}
}
void ProcessBlock(AudioNodeStream* aStream, GraphTime aFrom,
const AudioBlock& aInput, AudioBlock* aOutput,
bool* aFinished) override {
if (aInput.IsNull()) {
// mLeftOverData != INT_MIN means that the panning model was HRTF and a
// tail-time reference was added. Even if the model is now equalpower,
// the reference will need to be removed.
if (mLeftOverData > 0 &&
mPanningModelFunction == &PannerNodeEngine::HRTFPanningFunction) {
mLeftOverData -= WEBAUDIO_BLOCK_SIZE;
} else {
if (mLeftOverData != INT_MIN) {
mLeftOverData = INT_MIN;
aStream->ScheduleCheckForInactive();
mHRTFPanner->reset();
RefPtr<PlayingRefChangeHandler> refchanged =
new PlayingRefChangeHandler(aStream,
PlayingRefChangeHandler::RELEASE);
aStream->Graph()->DispatchToMainThreadStableState(
refchanged.forget());
}
aOutput->SetNull(WEBAUDIO_BLOCK_SIZE);
return;
}
} else if (mPanningModelFunction ==
&PannerNodeEngine::HRTFPanningFunction) {
if (mLeftOverData == INT_MIN) {
RefPtr<PlayingRefChangeHandler> refchanged =
new PlayingRefChangeHandler(aStream,
PlayingRefChangeHandler::ADDREF);
aStream->Graph()->DispatchToMainThreadStableState(refchanged.forget());
}
mLeftOverData = mHRTFPanner->maxTailFrames();
}
StreamTime tick = mDestination->GraphTimeToStreamTime(aFrom);
(this->*mPanningModelFunction)(aInput, aOutput, tick);
}
bool IsActive() const override { return mLeftOverData != INT_MIN; }
void ComputeAzimuthAndElevation(const ThreeDPoint& position, float& aAzimuth,
float& aElevation);
float ComputeConeGain(const ThreeDPoint& position,
const ThreeDPoint& orientation);
// Compute how much the distance contributes to the gain reduction.
double ComputeDistanceGain(const ThreeDPoint& position);
void EqualPowerPanningFunction(const AudioBlock& aInput, AudioBlock* aOutput,
StreamTime tick);
void HRTFPanningFunction(const AudioBlock& aInput, AudioBlock* aOutput,
StreamTime tick);
float LinearGainFunction(double aDistance);
float InverseGainFunction(double aDistance);
float ExponentialGainFunction(double aDistance);
ThreeDPoint ConvertAudioParamTimelineTo3DP(AudioParamTimeline& aX,
AudioParamTimeline& aY,
AudioParamTimeline& aZ,
StreamTime& tick);
size_t SizeOfExcludingThis(MallocSizeOf aMallocSizeOf) const override {
size_t amount = AudioNodeEngine::SizeOfExcludingThis(aMallocSizeOf);
if (mHRTFPanner) {
amount += mHRTFPanner->sizeOfIncludingThis(aMallocSizeOf);
}
return amount;
}
size_t SizeOfIncludingThis(MallocSizeOf aMallocSizeOf) const override {
return aMallocSizeOf(this) + SizeOfExcludingThis(aMallocSizeOf);
}
RefPtr<AudioNodeStream> mDestination;
// This member is set on the main thread, but is not accessed on the rendering
// thread untile mPanningModelFunction has changed, and this happens strictly
// later, via a MediaStreamGraph ControlMessage.
nsAutoPtr<HRTFPanner> mHRTFPanner;
RefPtr<AudioListenerEngine> mListenerEngine;
typedef void (PannerNodeEngine::*PanningModelFunction)(
const AudioBlock& aInput, AudioBlock* aOutput, StreamTime tick);
PanningModelFunction mPanningModelFunction;
typedef float (PannerNodeEngine::*DistanceModelFunction)(double aDistance);
DistanceModelFunction mDistanceModelFunction;
AudioParamTimeline mPositionX;
AudioParamTimeline mPositionY;
AudioParamTimeline mPositionZ;
AudioParamTimeline mOrientationX;
AudioParamTimeline mOrientationY;
AudioParamTimeline mOrientationZ;
double mRefDistance;
double mMaxDistance;
double mRolloffFactor;
double mConeInnerAngle;
double mConeOuterAngle;
double mConeOuterGain;
int mLeftOverData;
};
PannerNode::PannerNode(AudioContext* aContext)
: AudioNode(aContext, 2, ChannelCountMode::Clamped_max,
ChannelInterpretation::Speakers)
// Please keep these default values consistent with
// PannerNodeEngine::PannerNodeEngine above.
,
mPanningModel(PanningModelType::Equalpower),
mDistanceModel(DistanceModelType::Inverse),
mRefDistance(1.),
mMaxDistance(10000.),
mRolloffFactor(1.),
mConeInnerAngle(360.),
mConeOuterAngle(360.),
mConeOuterGain(0.) {
CreateAudioParam(mPositionX, PannerNode::POSITIONX, this->NodeType(), 0.f);
CreateAudioParam(mPositionY, PannerNode::POSITIONY, this->NodeType(), 0.f);
CreateAudioParam(mPositionZ, PannerNode::POSITIONZ, this->NodeType(), 0.f);
CreateAudioParam(mOrientationX, PannerNode::ORIENTATIONX, this->NodeType(),
1.0f);
CreateAudioParam(mOrientationY, PannerNode::ORIENTATIONY, this->NodeType(),
0.f);
CreateAudioParam(mOrientationZ, PannerNode::ORIENTATIONZ, this->NodeType(),
0.f);
mStream = AudioNodeStream::Create(
aContext,
new PannerNodeEngine(this, aContext->Destination(),
aContext->Listener()->Engine()),
AudioNodeStream::NO_STREAM_FLAGS, aContext->Graph());
}
/* static */
already_AddRefed<PannerNode> PannerNode::Create(AudioContext& aAudioContext,
const PannerOptions& aOptions,
ErrorResult& aRv) {
RefPtr<PannerNode> audioNode = new PannerNode(&aAudioContext);
audioNode->Initialize(aOptions, aRv);
if (NS_WARN_IF(aRv.Failed())) {
return nullptr;
}
audioNode->SetPanningModel(aOptions.mPanningModel);
audioNode->SetDistanceModel(aOptions.mDistanceModel);
audioNode->SetPosition(aOptions.mPositionX, aOptions.mPositionY,
aOptions.mPositionZ);
audioNode->SetOrientation(aOptions.mOrientationX, aOptions.mOrientationY,
aOptions.mOrientationZ);
audioNode->SetRefDistance(aOptions.mRefDistance, aRv);
if (NS_WARN_IF(aRv.Failed())) {
return nullptr;
}
audioNode->SetMaxDistance(aOptions.mMaxDistance, aRv);
if (NS_WARN_IF(aRv.Failed())) {
return nullptr;
}
audioNode->SetRolloffFactor(aOptions.mRolloffFactor, aRv);
if (NS_WARN_IF(aRv.Failed())) {
return nullptr;
}
audioNode->SetConeInnerAngle(aOptions.mConeInnerAngle);
audioNode->SetConeOuterAngle(aOptions.mConeOuterAngle);
audioNode->SetConeOuterGain(aOptions.mConeOuterGain, aRv);
if (NS_WARN_IF(aRv.Failed())) {
return nullptr;
}
return audioNode.forget();
}
void PannerNode::SetPanningModel(PanningModelType aPanningModel) {
mPanningModel = aPanningModel;
if (mPanningModel == PanningModelType::HRTF) {
// We can set the engine's `mHRTFPanner` member here from the main thread,
// because the engine will not touch it from the MediaStreamGraph
// thread until the PANNING_MODEL message sent below is received.
static_cast<PannerNodeEngine*>(mStream->Engine())->CreateHRTFPanner();
}
SendInt32ParameterToStream(PANNING_MODEL, int32_t(mPanningModel));
}
size_t PannerNode::SizeOfExcludingThis(MallocSizeOf aMallocSizeOf) const {
return AudioNode::SizeOfExcludingThis(aMallocSizeOf);
}
size_t PannerNode::SizeOfIncludingThis(MallocSizeOf aMallocSizeOf) const {
return aMallocSizeOf(this) + SizeOfExcludingThis(aMallocSizeOf);
}
JSObject* PannerNode::WrapObject(JSContext* aCx,
JS::Handle<JSObject*> aGivenProto) {
return PannerNode_Binding::Wrap(aCx, this, aGivenProto);
}
// Those three functions are described in the spec.
float PannerNodeEngine::LinearGainFunction(double aDistance) {
return 1 - mRolloffFactor *
(std::max(std::min(aDistance, mMaxDistance), mRefDistance) -
mRefDistance) /
(mMaxDistance - mRefDistance);
}
float PannerNodeEngine::InverseGainFunction(double aDistance) {
return mRefDistance /
(mRefDistance +
mRolloffFactor * (std::max(aDistance, mRefDistance) - mRefDistance));
}
float PannerNodeEngine::ExponentialGainFunction(double aDistance) {
return pow(std::max(aDistance, mRefDistance) / mRefDistance, -mRolloffFactor);
}
void PannerNodeEngine::HRTFPanningFunction(const AudioBlock& aInput,
AudioBlock* aOutput,
StreamTime tick) {
// The output of this node is always stereo, no matter what the inputs are.
aOutput->AllocateChannels(2);
float azimuth, elevation;
ThreeDPoint position =
ConvertAudioParamTimelineTo3DP(mPositionX, mPositionY, mPositionZ, tick);
ThreeDPoint orientation = ConvertAudioParamTimelineTo3DP(
mOrientationX, mOrientationY, mOrientationZ, tick);
if (!orientation.IsZero()) {
orientation.Normalize();
}
ComputeAzimuthAndElevation(position, azimuth, elevation);
AudioBlock input = aInput;
// Gain is applied before the delay and convolution of the HRTF.
input.mVolume *=
ComputeConeGain(position, orientation) * ComputeDistanceGain(position);
mHRTFPanner->pan(azimuth, elevation, &input, aOutput);
}
ThreeDPoint PannerNodeEngine::ConvertAudioParamTimelineTo3DP(
AudioParamTimeline& aX, AudioParamTimeline& aY, AudioParamTimeline& aZ,
StreamTime& tick) {
return ThreeDPoint(aX.GetValueAtTime(tick), aY.GetValueAtTime(tick),
aZ.GetValueAtTime(tick));
}
void PannerNodeEngine::EqualPowerPanningFunction(const AudioBlock& aInput,
AudioBlock* aOutput,
StreamTime tick) {
float azimuth, elevation, gainL, gainR, normalizedAzimuth, distanceGain,
coneGain;
int inputChannels = aInput.ChannelCount();
// Optimize the case where the position and orientation is constant for this
// processing block: we can just apply a constant gain on the left and right
// channel
if (mPositionX.HasSimpleValue() && mPositionY.HasSimpleValue() &&
mPositionZ.HasSimpleValue() && mOrientationX.HasSimpleValue() &&
mOrientationY.HasSimpleValue() && mOrientationZ.HasSimpleValue()) {
ThreeDPoint position = ConvertAudioParamTimelineTo3DP(
mPositionX, mPositionY, mPositionZ, tick);
ThreeDPoint orientation = ConvertAudioParamTimelineTo3DP(
mOrientationX, mOrientationY, mOrientationZ, tick);
if (!orientation.IsZero()) {
orientation.Normalize();
}
// For a stereo source, when both the listener and the panner are in
// the same spot, and no cone gain is specified, this node is noop.
if (inputChannels == 2 && mListenerEngine->Position() == position &&
mConeInnerAngle == 360 && mConeOuterAngle == 360) {
*aOutput = aInput;
return;
}
ComputeAzimuthAndElevation(position, azimuth, elevation);
coneGain = ComputeConeGain(position, orientation);
// The following algorithm is described in the spec.
// Clamp azimuth in the [-90, 90] range.
azimuth = min(180.f, max(-180.f, azimuth));
// Wrap around
if (azimuth < -90.f) {
azimuth = -180.f - azimuth;
} else if (azimuth > 90) {
azimuth = 180.f - azimuth;
}
// Normalize the value in the [0, 1] range.
if (inputChannels == 1) {
normalizedAzimuth = (azimuth + 90.f) / 180.f;
} else {
if (azimuth <= 0) {
normalizedAzimuth = (azimuth + 90.f) / 90.f;
} else {
normalizedAzimuth = azimuth / 90.f;
}
}
distanceGain = ComputeDistanceGain(position);
// Actually compute the left and right gain.
gainL = cos(0.5 * M_PI * normalizedAzimuth);
gainR = sin(0.5 * M_PI * normalizedAzimuth);
// Compute the output.
ApplyStereoPanning(aInput, aOutput, gainL, gainR, azimuth <= 0);
aOutput->mVolume *= distanceGain * coneGain;
} else {
float positionX[WEBAUDIO_BLOCK_SIZE];
float positionY[WEBAUDIO_BLOCK_SIZE];
float positionZ[WEBAUDIO_BLOCK_SIZE];
float orientationX[WEBAUDIO_BLOCK_SIZE];
float orientationY[WEBAUDIO_BLOCK_SIZE];
float orientationZ[WEBAUDIO_BLOCK_SIZE];
if (!mPositionX.HasSimpleValue()) {
mPositionX.GetValuesAtTime(tick, positionX, WEBAUDIO_BLOCK_SIZE);
} else {
positionX[0] = mPositionX.GetValueAtTime(tick);
}
if (!mPositionY.HasSimpleValue()) {
mPositionY.GetValuesAtTime(tick, positionY, WEBAUDIO_BLOCK_SIZE);
} else {
positionY[0] = mPositionY.GetValueAtTime(tick);
}
if (!mPositionZ.HasSimpleValue()) {
mPositionZ.GetValuesAtTime(tick, positionZ, WEBAUDIO_BLOCK_SIZE);
} else {
positionZ[0] = mPositionZ.GetValueAtTime(tick);
}
if (!mOrientationX.HasSimpleValue()) {
mOrientationX.GetValuesAtTime(tick, orientationX, WEBAUDIO_BLOCK_SIZE);
} else {
orientationX[0] = mOrientationX.GetValueAtTime(tick);
}
if (!mOrientationY.HasSimpleValue()) {
mOrientationY.GetValuesAtTime(tick, orientationY, WEBAUDIO_BLOCK_SIZE);
} else {
orientationY[0] = mOrientationY.GetValueAtTime(tick);
}
if (!mOrientationZ.HasSimpleValue()) {
mOrientationZ.GetValuesAtTime(tick, orientationZ, WEBAUDIO_BLOCK_SIZE);
} else {
orientationZ[0] = mOrientationZ.GetValueAtTime(tick);
}
float buffer[3 * WEBAUDIO_BLOCK_SIZE + 4];
bool onLeft[WEBAUDIO_BLOCK_SIZE];
float* alignedPanningL = ALIGNED16(buffer);
float* alignedPanningR = alignedPanningL + WEBAUDIO_BLOCK_SIZE;
float* alignedGain = alignedPanningR + WEBAUDIO_BLOCK_SIZE;
ASSERT_ALIGNED16(alignedPanningL);
ASSERT_ALIGNED16(alignedPanningR);
ASSERT_ALIGNED16(alignedGain);
for (size_t counter = 0; counter < WEBAUDIO_BLOCK_SIZE; ++counter) {
ThreeDPoint position(
mPositionX.HasSimpleValue() ? positionX[0] : positionX[counter],
mPositionY.HasSimpleValue() ? positionY[0] : positionY[counter],
mPositionZ.HasSimpleValue() ? positionZ[0] : positionZ[counter]);
ThreeDPoint orientation(
mOrientationX.HasSimpleValue() ? orientationX[0]
: orientationX[counter],
mOrientationY.HasSimpleValue() ? orientationY[0]
: orientationY[counter],
mOrientationZ.HasSimpleValue() ? orientationZ[0]
: orientationZ[counter]);
if (!orientation.IsZero()) {
orientation.Normalize();
}
ComputeAzimuthAndElevation(position, azimuth, elevation);
coneGain = ComputeConeGain(position, orientation);
// The following algorithm is described in the spec.
// Clamp azimuth in the [-90, 90] range.
azimuth = min(180.f, max(-180.f, azimuth));
// Wrap around
if (azimuth < -90.f) {
azimuth = -180.f - azimuth;
} else if (azimuth > 90) {
azimuth = 180.f - azimuth;
}
// Normalize the value in the [0, 1] range.
if (inputChannels == 1) {
normalizedAzimuth = (azimuth + 90.f) / 180.f;
} else {
if (azimuth <= 0) {
normalizedAzimuth = (azimuth + 90.f) / 90.f;
} else {
normalizedAzimuth = azimuth / 90.f;
}
}
distanceGain = ComputeDistanceGain(position);
// Actually compute the left and right gain.
float gainL = cos(0.5 * M_PI * normalizedAzimuth);
float gainR = sin(0.5 * M_PI * normalizedAzimuth);
alignedPanningL[counter] = gainL;
alignedPanningR[counter] = gainR;
alignedGain[counter] = distanceGain * coneGain;
onLeft[counter] = azimuth <= 0;
}
// Apply the panning to the output buffer
ApplyStereoPanning(aInput, aOutput, alignedPanningL, alignedPanningR,
onLeft);
// Apply the input volume, cone and distance gain to the output buffer.
float* outputL = aOutput->ChannelFloatsForWrite(0);
float* outputR = aOutput->ChannelFloatsForWrite(1);
AudioBlockInPlaceScale(outputL, alignedGain);
AudioBlockInPlaceScale(outputR, alignedGain);
}
}
// This algorithm is specified in the webaudio spec.
void PannerNodeEngine::ComputeAzimuthAndElevation(const ThreeDPoint& position,
float& aAzimuth,
float& aElevation) {
ThreeDPoint sourceListener = position - mListenerEngine->Position();
if (sourceListener.IsZero()) {
aAzimuth = 0.0;
aElevation = 0.0;
return;
}
sourceListener.Normalize();
// Project the source-listener vector on the x-z plane.
const ThreeDPoint& listenerFront = mListenerEngine->FrontVector();
const ThreeDPoint& listenerRight = mListenerEngine->RightVector();
ThreeDPoint up = listenerRight.CrossProduct(listenerFront);
double upProjection = sourceListener.DotProduct(up);
aElevation = 90 - 180 * acos(upProjection) / M_PI;
if (aElevation > 90) {
aElevation = 180 - aElevation;
} else if (aElevation < -90) {
aElevation = -180 - aElevation;
}
ThreeDPoint projectedSource = sourceListener - up * upProjection;
if (projectedSource.IsZero()) {
// source - listener direction is up or down.
aAzimuth = 0.0;
return;
}
projectedSource.Normalize();
// Actually compute the angle, and convert to degrees
double projection = projectedSource.DotProduct(listenerRight);
aAzimuth = 180 * acos(projection) / M_PI;
// Compute whether the source is in front or behind the listener.
double frontBack = projectedSource.DotProduct(listenerFront);
if (frontBack < 0) {
aAzimuth = 360 - aAzimuth;
}
// Rotate the azimuth so it is relative to the listener front vector instead
// of the right vector.
if ((aAzimuth >= 0) && (aAzimuth <= 270)) {
aAzimuth = 90 - aAzimuth;
} else {
aAzimuth = 450 - aAzimuth;
}
}
// This algorithm is described in the WebAudio spec.
float PannerNodeEngine::ComputeConeGain(const ThreeDPoint& position,
const ThreeDPoint& orientation) {
// Omnidirectional source
if (orientation.IsZero() ||
((mConeInnerAngle == 360) && (mConeOuterAngle == 360))) {
return 1;
}
// Normalized source-listener vector
ThreeDPoint sourceToListener = mListenerEngine->Position() - position;
sourceToListener.Normalize();
// Angle between the source orientation vector and the source-listener vector
double dotProduct = sourceToListener.DotProduct(orientation);
double angle = 180 * acos(dotProduct) / M_PI;
double absAngle = fabs(angle);
// Divide by 2 here since API is entire angle (not half-angle)
double absInnerAngle = fabs(mConeInnerAngle) / 2;
double absOuterAngle = fabs(mConeOuterAngle) / 2;
double gain = 1;
if (absAngle <= absInnerAngle) {
// No attenuation
gain = 1;
} else if (absAngle >= absOuterAngle) {
// Max attenuation
gain = mConeOuterGain;
} else {
// Between inner and outer cones
// inner -> outer, x goes from 0 -> 1
double x = (absAngle - absInnerAngle) / (absOuterAngle - absInnerAngle);
gain = (1 - x) + mConeOuterGain * x;
}
return gain;
}
double PannerNodeEngine::ComputeDistanceGain(const ThreeDPoint& position) {
ThreeDPoint distanceVec = position - mListenerEngine->Position();
float distance = sqrt(distanceVec.DotProduct(distanceVec));
return std::max(0.0f, (this->*mDistanceModelFunction)(distance));
}
} // namespace dom
} // namespace mozilla
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