void PannerNode::calculateAzimuthElevation(double* outAzimuth, double* outElevation)
{
double azimuth = 0.0;
// Calculate the source-listener vector
FloatPoint3D listenerPosition = listener()->position();
FloatPoint3D sourceListener = m_position - listenerPosition;
// normalize() does nothing if the length of |sourceListener| is zero.
sourceListener.normalize();
// Align axes
FloatPoint3D listenerFront = listener()->orientation();
FloatPoint3D listenerUp = listener()->upVector();
FloatPoint3D listenerRight = listenerFront.cross(listenerUp);
listenerRight.normalize();
FloatPoint3D listenerFrontNorm = listenerFront;
listenerFrontNorm.normalize();
FloatPoint3D up = listenerRight.cross(listenerFrontNorm);
float upProjection = sourceListener.dot(up);
FloatPoint3D projectedSource = sourceListener - upProjection * up;
projectedSource.normalize();
azimuth = 180.0 * acos(projectedSource.dot(listenerRight)) / piDouble;
fixNANs(azimuth); // avoid illegal values
// Source in front or behind the listener
double frontBack = projectedSource.dot(listenerFrontNorm);
if (frontBack < 0.0)
azimuth = 360.0 - azimuth;
// Make azimuth relative to "front" and not "right" listener vector
if ((azimuth >= 0.0) && (azimuth <= 270.0))
azimuth = 90.0 - azimuth;
else
azimuth = 450.0 - azimuth;
// Elevation
double elevation = 90.0 - 180.0 * acos(sourceListener.dot(up)) / piDouble;
fixNANs(elevation); // avoid illegal values
if (elevation > 90.0)
elevation = 180.0 - elevation;
else if (elevation < -90.0)
elevation = -180.0 - elevation;
if (outAzimuth)
*outAzimuth = azimuth;
if (outElevation)
*outElevation = elevation;
}
double PannerNode::calculateDopplerRate()
{
double dopplerShift = 1.0;
double dopplerFactor = listener()->dopplerFactor();
if (dopplerFactor > 0.0) {
double speedOfSound = listener()->speedOfSound();
const FloatPoint3D &sourceVelocity = m_velocity;
const FloatPoint3D &listenerVelocity = listener()->velocity();
// Don't bother if both source and listener have no velocity
bool sourceHasVelocity = !sourceVelocity.isZero();
bool listenerHasVelocity = !listenerVelocity.isZero();
if (sourceHasVelocity || listenerHasVelocity) {
// Calculate the source to listener vector
FloatPoint3D listenerPosition = listener()->position();
FloatPoint3D sourceToListener = m_position - listenerPosition;
double sourceListenerMagnitude = sourceToListener.length();
if (!sourceListenerMagnitude) {
// Source and listener are at the same position. Skip the computation of the doppler
// shift, and just return the cached value.
dopplerShift = m_cachedDopplerRate;
} else {
double listenerProjection = sourceToListener.dot(listenerVelocity) / sourceListenerMagnitude;
double sourceProjection = sourceToListener.dot(sourceVelocity) / sourceListenerMagnitude;
listenerProjection = -listenerProjection;
sourceProjection = -sourceProjection;
double scaledSpeedOfSound = speedOfSound / dopplerFactor;
listenerProjection = std::min(listenerProjection, scaledSpeedOfSound);
sourceProjection = std::min(sourceProjection, scaledSpeedOfSound);
dopplerShift = ((speedOfSound - dopplerFactor * listenerProjection) / (speedOfSound - dopplerFactor * sourceProjection));
fixNANs(dopplerShift); // avoid illegal values
// Limit the pitch shifting to 4 octaves up and 3 octaves down.
if (dopplerShift > 16.0)
dopplerShift = 16.0;
else if (dopplerShift < 0.125)
dopplerShift = 0.125;
}
}
}
return dopplerShift;
}
float PannerNode::dopplerRate(ContextRenderLock& r)
{
double dopplerShift = 1.0;
// FIXME: optimize for case when neither source nor listener has changed...
double dopplerFactor = listener(r)->dopplerFactor();
if (dopplerFactor > 0.0)
{
double speedOfSound = listener(r)->speedOfSound();
const FloatPoint3D &sourceVelocity = m_velocity;
const FloatPoint3D &listenerVelocity = listener(r)->velocity();
// Don't bother if both source and listener have no velocity
bool sourceHasVelocity = !sourceVelocity.isZero();
bool listenerHasVelocity = !listenerVelocity.isZero();
if (sourceHasVelocity || listenerHasVelocity)
{
// Calculate the source to listener vector
FloatPoint3D listenerPosition = listener(r)->position();
FloatPoint3D sourceToListener = m_position - listenerPosition;
double sourceListenerMagnitude = sourceToListener.length();
double listenerProjection = sourceToListener.dot(listenerVelocity) / sourceListenerMagnitude;
double sourceProjection = sourceToListener.dot(sourceVelocity) / sourceListenerMagnitude;
listenerProjection = -listenerProjection;
sourceProjection = -sourceProjection;
double scaledSpeedOfSound = speedOfSound / dopplerFactor;
listenerProjection = min(listenerProjection, scaledSpeedOfSound);
sourceProjection = min(sourceProjection, scaledSpeedOfSound);
dopplerShift = ((speedOfSound - dopplerFactor * listenerProjection) / (speedOfSound - dopplerFactor * sourceProjection));
fixNANs(dopplerShift); // avoid illegal values
// Limit the pitch shifting to 4 octaves up and 3 octaves down.
if (dopplerShift > 16.0)
dopplerShift = 16.0;
else if (dopplerShift < 0.125)
dopplerShift = 0.125;
}
}
return static_cast<float>(dopplerShift);
}
void PannerNode::getAzimuthElevation(double* outAzimuth, double* outElevation)
{
// FIXME: we should cache azimuth and elevation (if possible), so we only re-calculate if a change has been made.
double azimuth = 0.0;
// Calculate the source-listener vector
FloatPoint3D listenerPosition = listener()->position();
FloatPoint3D sourceListener = m_position - listenerPosition;
if (sourceListener.isZero()) {
// degenerate case if source and listener are at the same point
*outAzimuth = 0.0;
*outElevation = 0.0;
return;
}
sourceListener.normalize();
// Align axes
FloatPoint3D listenerFront = listener()->orientation();
FloatPoint3D listenerUp = listener()->upVector();
FloatPoint3D listenerRight = listenerFront.cross(listenerUp);
listenerRight.normalize();
FloatPoint3D listenerFrontNorm = listenerFront;
listenerFrontNorm.normalize();
FloatPoint3D up = listenerRight.cross(listenerFrontNorm);
float upProjection = sourceListener.dot(up);
FloatPoint3D projectedSource = sourceListener - upProjection * up;
projectedSource.normalize();
azimuth = 180.0 * acos(projectedSource.dot(listenerRight)) / piDouble;
fixNANs(azimuth); // avoid illegal values
// Source in front or behind the listener
double frontBack = projectedSource.dot(listenerFrontNorm);
if (frontBack < 0.0)
azimuth = 360.0 - azimuth;
// Make azimuth relative to "front" and not "right" listener vector
if ((azimuth >= 0.0) && (azimuth <= 270.0))
azimuth = 90.0 - azimuth;
else
azimuth = 450.0 - azimuth;
// Elevation
double elevation = 90.0 - 180.0 * acos(sourceListener.dot(up)) / piDouble;
fixNANs(elevation); // avoid illegal values
if (elevation > 90.0)
elevation = 180.0 - elevation;
else if (elevation < -90.0)
elevation = -180.0 - elevation;
if (outAzimuth)
*outAzimuth = azimuth;
if (outElevation)
*outElevation = elevation;
}
