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#include "effects/builtin/tremoloeffect.h"
namespace {
// Used to avoid gain discontinuities when changing parameters too fast
constexpr double kMaxGainIncrement = 0.001;
}
// static
QString TremoloEffect::getId() {
return "org.mixxx.effects.tremolo";
}
// static
EffectManifestPointer TremoloEffect::getManifest() {
EffectManifestPointer pManifest(new EffectManifest());
pManifest->setId(getId());
pManifest->setName(QObject::tr("Tremolo"));
pManifest->setShortName(QObject::tr("Tremolo"));
pManifest->setAuthor("The Mixxx Team");
pManifest->setVersion("1.0");
pManifest->setDescription(QObject::tr(
"Cycles the volume up and down"));
pManifest->setMetaknobDefault(1.0);
EffectManifestParameterPointer depth = pManifest->addParameter();
depth->setId("depth");
depth->setName(QObject::tr("Depth"));
depth->setShortName(QObject::tr("Depth"));
depth->setDescription(QObject::tr(
"How much the effect changes the volume"));
depth->setControlHint(EffectManifestParameter::ControlHint::KNOB_LINEAR);
depth->setSemanticHint(EffectManifestParameter::SemanticHint::UNKNOWN);
depth->setUnitsHint(EffectManifestParameter::UnitsHint::UNKNOWN);
depth->setDefaultLinkType(EffectManifestParameter::LinkType::LINKED);
depth->setDefault(1);
depth->setMinimum(0);
depth->setMaximum(1);
EffectManifestParameterPointer rate = pManifest->addParameter();
rate->setId("rate");
rate->setName(QObject::tr("Rate"));
rate->setShortName(QObject::tr("Rate"));
rate->setDescription(QObject::tr(
"Rate of the volume changes\n"
"4 beats - 1/8 beat if tempo is detected\n"
"1/4 Hz - 8 Hz if no tempo is detected"));
rate->setControlHint(
EffectManifestParameter::ControlHint::KNOB_LOGARITHMIC);
rate->setSemanticHint(EffectManifestParameter::SemanticHint::UNKNOWN);
rate->setUnitsHint(EffectManifestParameter::UnitsHint::BEATS);
rate->setDefault(1);
rate->setMinimum(1.0/4);
rate->setMaximum(8);
EffectManifestParameterPointer width = pManifest->addParameter();
width->setId("width");
width->setName(QObject::tr("Width"));
width->setShortName(QObject::tr("Width"));
width->setDescription(QObject::tr(
"Width of the volume peak\n"
"10% - 90% of the effect period"));
width->setControlHint(EffectManifestParameter::ControlHint::KNOB_LINEAR);
width->setSemanticHint(EffectManifestParameter::SemanticHint::UNKNOWN);
width->setUnitsHint(EffectManifestParameter::UnitsHint::UNKNOWN);
width->setMinimum(0.1);
width->setDefault(0.5);
width->setMaximum(0.9);
EffectManifestParameterPointer waveform = pManifest->addParameter();
waveform->setId("waveform");
waveform->setName(QObject::tr("Waveform"));
waveform->setShortName(QObject::tr("Waveform"));
waveform->setDescription(QObject::tr(
"Shape of the volume modulation wave\n"
"Fully left: Square wave\n"
"Fully right: Sine wave"));
waveform->setControlHint(
EffectManifestParameter::ControlHint::KNOB_LOGARITHMIC);
waveform->setSemanticHint(EffectManifestParameter::SemanticHint::UNKNOWN);
waveform->setUnitsHint(EffectManifestParameter::UnitsHint::UNKNOWN);
waveform->setMinimum(0.005);
waveform->setDefault(0.5);
waveform->setMaximum(1);
EffectManifestParameterPointer phase = pManifest->addParameter();
phase->setId("phase");
phase->setName(QObject::tr("Phase"));
phase->setShortName(QObject::tr("Phase"));
phase->setDescription(QObject::tr(
"Shifts the position of the volume peak within the period\n"
"Fully left: beginning of the effect period\n"
"Fully right: end of the effect period"));
phase->setControlHint(
EffectManifestParameter::ControlHint::KNOB_LINEAR);
phase->setSemanticHint(EffectManifestParameter::SemanticHint::UNKNOWN);
phase->setUnitsHint(EffectManifestParameter::UnitsHint::UNKNOWN);
phase->setDefault(0);
phase->setMinimum(0);
phase->setMaximum(1);
EffectManifestParameterPointer quantize = pManifest->addParameter();
quantize->setId("quantize");
quantize->setName(QObject::tr("Quantize"));
quantize->setShortName(QObject::tr("Quantize"));
quantize->setDescription(QObject::tr(
"Round the Rate parameter to the nearest whole division of a beat."));
quantize->setControlHint(
EffectManifestParameter::ControlHint::TOGGLE_STEPPING);
quantize->setSemanticHint(EffectManifestParameter::SemanticHint::UNKNOWN);
quantize->setUnitsHint(EffectManifestParameter::UnitsHint::UNKNOWN);
quantize->setDefault(1);
quantize->setMinimum(0);
quantize->setMaximum(1);
EffectManifestParameterPointer triplet = pManifest->addParameter();
triplet->setId("triplet");
triplet->setName(QObject::tr("Triplets"));
triplet->setShortName(QObject::tr("Triplet"));
triplet->setDescription(QObject::tr(
"When the Quantize parameter is enabled, divide the effect period by 3."));
triplet->setControlHint(
EffectManifestParameter::ControlHint::TOGGLE_STEPPING);
triplet->setSemanticHint(EffectManifestParameter::SemanticHint::UNKNOWN);
triplet->setUnitsHint(EffectManifestParameter::UnitsHint::UNKNOWN);
triplet->setDefault(0);
triplet->setMinimum(0);
triplet->setMaximum(1);
return pManifest;
}
TremoloEffect::TremoloEffect(EngineEffect* pEffect)
: m_pDepthParameter(pEffect->getParameterById("depth")),
m_pRateParameter(pEffect->getParameterById("rate")),
m_pWidthParameter(pEffect->getParameterById("width")),
m_pWaveformParameter(pEffect->getParameterById("waveform")),
m_pPhaseParameter(pEffect->getParameterById("phase")),
m_pQuantizeParameter(pEffect->getParameterById("quantize")),
m_pTripletParameter(pEffect->getParameterById("triplet")) {
}
void TremoloEffect::processChannel(const ChannelHandle& handle,
TremoloState* pState,
const CSAMPLE* pInput, CSAMPLE* pOutput,
const mixxx::EngineParameters& bufferParameters,
const EffectEnableState enableState,
const GroupFeatureState& groupFeatures) {
Q_UNUSED(handle);
const double width = m_pWidthParameter->value();
const double smooth = m_pWaveformParameter->value();
const double depth = m_pDepthParameter->value();
unsigned int currentFrame = pState->currentFrame;
double gain = pState->gain;
const GroupFeatureState& gf = groupFeatures;
bool quantizeEnabling = !pState->quantizeEnabled
&& m_pQuantizeParameter->toBool();
bool tripletDisabling = pState->tripletEnabled
&& !m_pTripletParameter->toBool();
if (enableState == EffectEnableState::Enabling
|| quantizeEnabling
|| tripletDisabling) {
if (gf.has_beat_length_sec && gf.has_beat_fraction) {
currentFrame = static_cast<unsigned int>(gf.beat_fraction *
gf.beat_length_sec * bufferParameters.sampleRate());
} else {
currentFrame = 0;
}
gain = 0;
}
int framePerPeriod;
double rate = m_pRateParameter->value();
if (gf.has_beat_length_sec && gf.has_beat_fraction) {
if (m_pQuantizeParameter->toBool()) {
const auto divider = static_cast<int>(log2(rate));
rate = pow(2, divider);
if (m_pTripletParameter->toBool()) {
rate *= 3.0;
}
}
const auto framePerBeat = static_cast<int>(
gf.beat_length_sec * bufferParameters.sampleRate());
framePerPeriod = static_cast<int>(framePerBeat / rate);
} else {
framePerPeriod = static_cast<int>(bufferParameters.sampleRate() / rate);
}
const auto phaseOffsetFrame = static_cast<unsigned int>(
m_pPhaseParameter->value() * framePerPeriod);
currentFrame = currentFrame % framePerPeriod;
for (SINT i = 0;
i < bufferParameters.samplesPerBuffer();
i += bufferParameters.channelCount()) {
unsigned int positionFrame = (currentFrame - phaseOffsetFrame);
positionFrame = positionFrame % framePerPeriod;
// Relative position (0 to 1) in the period
double position = static_cast<double>(positionFrame) / framePerPeriod;
// Bend the position according to the width parameter
// This maps [0 width] to [0 0.5] and [width 1] to [0.5 1]
if (position < width) {
position = 0.5 / width * position;
} else {
position = 0.5 + 0.5 * (position - width) / (1 - width);
}
// This is where the magic happens
// This function gives the gain to apply for position in [0 1]
// Plot the function to get a grasp :
// From a sine to a square wave depending on the smooth parameter
double gainTarget = 1.0 - (depth / 2.0)
+ (atan(
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