andrewm@0: /* andrewm@0: This code accompanies the textbook: andrewm@0: andrewm@0: Digital Audio Effects: Theory, Implementation and Application andrewm@0: Joshua D. Reiss and Andrew P. McPherson andrewm@0: andrewm@0: --- andrewm@0: andrewm@0: Ring Modulator: modulation using a carrier oscillator andrewm@0: See textbook Chapter 5: Amplitude Modulation andrewm@0: andrewm@0: Code by Andrew McPherson, Brecht De Man and Joshua Reiss andrewm@0: andrewm@0: --- andrewm@0: andrewm@0: This program is free software: you can redistribute it and/or modify andrewm@0: it under the terms of the GNU General Public License as published by andrewm@0: the Free Software Foundation, either version 3 of the License, or andrewm@0: (at your option) any later version. andrewm@0: andrewm@0: This program is distributed in the hope that it will be useful, andrewm@0: but WITHOUT ANY WARRANTY; without even the implied warranty of andrewm@0: MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the andrewm@0: GNU General Public License for more details. andrewm@0: andrewm@0: You should have received a copy of the GNU General Public License andrewm@0: along with this program. If not, see . andrewm@0: */ andrewm@0: andrewm@0: #include "PluginProcessor.h" andrewm@0: #include "PluginEditor.h" andrewm@0: #include andrewm@0: andrewm@0: //============================================================================== andrewm@0: RingModulatorAudioProcessor::RingModulatorAudioProcessor() andrewm@0: { andrewm@0: // Set default values: andrewm@0: carrierFrequency_ = 100.0; andrewm@0: sweepWidth_ = 0.0; andrewm@0: lfoFrequency_ = 1.0; andrewm@0: waveform_ = kWaveformSine; andrewm@0: andrewm@0: lfoPhase_ = carrierPhase_ = 0.0; andrewm@0: inverseSampleRate_ = 1.0/44100.0; andrewm@0: andrewm@0: lastUIWidth_ = 370; andrewm@0: lastUIHeight_ = 160; andrewm@0: } andrewm@0: andrewm@0: RingModulatorAudioProcessor::~RingModulatorAudioProcessor() andrewm@0: { andrewm@0: } andrewm@0: andrewm@0: //============================================================================== andrewm@0: const String RingModulatorAudioProcessor::getName() const andrewm@0: { andrewm@0: return JucePlugin_Name; andrewm@0: } andrewm@0: andrewm@0: int RingModulatorAudioProcessor::getNumParameters() andrewm@0: { andrewm@0: return kNumParameters; andrewm@0: } andrewm@0: andrewm@0: float RingModulatorAudioProcessor::getParameter (int index) andrewm@0: { andrewm@0: // This method will be called by the host, probably on the audio thread, so andrewm@0: // it's absolutely time-critical. Don't use critical sections or anything andrewm@0: // UI-related, or anything at all that may block in any way! andrewm@0: switch (index) andrewm@0: { andrewm@0: case kCarrierFrequencyParam: return carrierFrequency_; andrewm@0: case kSweepWidthParam: return sweepWidth_; andrewm@0: case kLFOFrequencyParam: return lfoFrequency_; andrewm@0: case kWaveformParam: return (float)waveform_; andrewm@0: default: return 0.0f; andrewm@0: } andrewm@0: } andrewm@0: andrewm@0: void RingModulatorAudioProcessor::setParameter (int index, float newValue) andrewm@0: { andrewm@0: // This method will be called by the host, probably on the audio thread, so andrewm@0: // it's absolutely time-critical. Don't use critical sections or anything andrewm@0: // UI-related, or anything at all that may block in any way! andrewm@0: andrewm@0: switch (index) andrewm@0: { andrewm@0: case kCarrierFrequencyParam: andrewm@0: carrierFrequency_ = newValue; andrewm@0: break; andrewm@0: case kSweepWidthParam: andrewm@0: sweepWidth_ = newValue; andrewm@0: break; andrewm@0: case kLFOFrequencyParam: andrewm@0: lfoFrequency_ = newValue; andrewm@0: break; andrewm@0: case kWaveformParam: andrewm@0: waveform_ = (int)newValue; andrewm@0: break; andrewm@0: default: andrewm@0: break; andrewm@0: } andrewm@0: } andrewm@0: andrewm@0: const String RingModulatorAudioProcessor::getParameterName (int index) andrewm@0: { andrewm@0: switch (index) andrewm@0: { andrewm@0: case kCarrierFrequencyParam: return "carrier frequency"; andrewm@0: case kSweepWidthParam: return "LFO sweep width"; andrewm@0: case kLFOFrequencyParam: return "LFO frequency"; andrewm@0: case kWaveformParam: return "LFO waveform"; andrewm@0: default: break; andrewm@0: } andrewm@0: andrewm@0: return String::empty; andrewm@0: } andrewm@0: andrewm@0: const String RingModulatorAudioProcessor::getParameterText (int index) andrewm@0: { andrewm@0: return String (getParameter (index), 2); andrewm@0: } andrewm@0: andrewm@0: const String RingModulatorAudioProcessor::getInputChannelName (int channelIndex) const andrewm@0: { andrewm@0: return String (channelIndex + 1); andrewm@0: } andrewm@0: andrewm@0: const String RingModulatorAudioProcessor::getOutputChannelName (int channelIndex) const andrewm@0: { andrewm@0: return String (channelIndex + 1); andrewm@0: } andrewm@0: andrewm@0: bool RingModulatorAudioProcessor::isInputChannelStereoPair (int index) const andrewm@0: { andrewm@0: return true; andrewm@0: } andrewm@0: andrewm@0: bool RingModulatorAudioProcessor::isOutputChannelStereoPair (int index) const andrewm@0: { andrewm@0: return true; andrewm@0: } andrewm@0: andrewm@0: bool RingModulatorAudioProcessor::silenceInProducesSilenceOut() const andrewm@0: { andrewm@0: #if JucePlugin_SilenceInProducesSilenceOut andrewm@0: return true; andrewm@0: #else andrewm@0: return false; andrewm@0: #endif andrewm@0: } andrewm@0: andrewm@0: double RingModulatorAudioProcessor::getTailLengthSeconds() const andrewm@0: { andrewm@0: return 0.0; andrewm@0: } andrewm@0: andrewm@0: bool RingModulatorAudioProcessor::acceptsMidi() const andrewm@0: { andrewm@0: #if JucePlugin_WantsMidiInput andrewm@0: return true; andrewm@0: #else andrewm@0: return false; andrewm@0: #endif andrewm@0: } andrewm@0: andrewm@0: bool RingModulatorAudioProcessor::producesMidi() const andrewm@0: { andrewm@0: #if JucePlugin_ProducesMidiOutput andrewm@0: return true; andrewm@0: #else andrewm@0: return false; andrewm@0: #endif andrewm@0: } andrewm@0: andrewm@0: int RingModulatorAudioProcessor::getNumPrograms() andrewm@0: { andrewm@0: return 0; andrewm@0: } andrewm@0: andrewm@0: int RingModulatorAudioProcessor::getCurrentProgram() andrewm@0: { andrewm@0: return 0; andrewm@0: } andrewm@0: andrewm@0: void RingModulatorAudioProcessor::setCurrentProgram (int index) andrewm@0: { andrewm@0: } andrewm@0: andrewm@0: const String RingModulatorAudioProcessor::getProgramName (int index) andrewm@0: { andrewm@0: return String::empty; andrewm@0: } andrewm@0: andrewm@0: void RingModulatorAudioProcessor::changeProgramName (int index, const String& newName) andrewm@0: { andrewm@0: } andrewm@0: andrewm@0: //============================================================================== andrewm@0: void RingModulatorAudioProcessor::prepareToPlay (double sampleRate, int samplesPerBlock) andrewm@0: { andrewm@0: // Calculations that happen before play begins. Pretty simple in this effect, just andrewm@0: // reset the previous state. andrewm@0: lfoPhase_ = 0.0; andrewm@0: carrierPhase_ = 0.0; andrewm@0: inverseSampleRate_ = 1.0/sampleRate; andrewm@0: } andrewm@0: andrewm@0: void RingModulatorAudioProcessor::releaseResources() andrewm@0: { andrewm@0: // When playback stops, you can use this as an opportunity to free up any andrewm@0: // spare memory, etc. andrewm@0: } andrewm@0: andrewm@0: void RingModulatorAudioProcessor::reset() andrewm@0: { andrewm@0: // Use this method as the place to clear any delay lines, buffers, etc, as it andrewm@0: // means there's been a break in the audio's continuity. andrewm@0: andrewm@0: lfoPhase_ = 0.0; andrewm@0: carrierPhase_ = 0.0; andrewm@0: } andrewm@0: andrewm@0: andrewm@0: void RingModulatorAudioProcessor::processBlock (AudioSampleBuffer& buffer, MidiBuffer& midiMessages) andrewm@0: { andrewm@0: // Helpful information about this block of samples: andrewm@0: const int numInputChannels = getNumInputChannels(); // How many input channels for our effect? andrewm@0: const int numOutputChannels = getNumOutputChannels(); // How many output channels for our effect? andrewm@0: const int numSamples = buffer.getNumSamples(); // How many samples in the buffer for this block? andrewm@0: andrewm@0: int channel; andrewm@0: float cph, lph; andrewm@0: andrewm@0: // Go through each channel of audio that's passed in. In this example we apply identical andrewm@0: // effects to each channel, regardless of how many input channels there are. For some effects, like andrewm@0: // a stereo chorus or panner, you might do something different for each channel. andrewm@0: andrewm@0: for (channel = 0; channel < numInputChannels; ++channel) andrewm@0: { andrewm@0: // channelData is an array of length numSamples which contains the audio for one channel b@1: float* channelData = buffer.getWritePointer(channel); andrewm@0: andrewm@0: // Make a temporary copy of any state variables declared in PluginProcessor.h which need to be andrewm@0: // maintained between calls to processBlock(). Each channel needs to be processed identically andrewm@0: // which means that the activity of processing one channel can't affect the state variable for andrewm@0: // the next channel. andrewm@0: andrewm@0: cph = carrierPhase_; andrewm@0: lph = lfoPhase_; andrewm@0: andrewm@0: for (int i = 0; i < numSamples; ++i) andrewm@0: { andrewm@0: const float in = channelData[i]; andrewm@0: andrewm@0: // Ring modulation is easy! Just multiply the waveform by a periodic carrier andrewm@0: channelData[i] = in * sinf(2.0 * M_PI * cph); andrewm@0: andrewm@0: // Update the carrier and LFO phases, keeping them in the range 0-1 andrewm@0: lph += lfoFrequency_*inverseSampleRate_; andrewm@0: if(lph >= 1.0) andrewm@0: lph -= 1.0; andrewm@0: cph += (carrierFrequency_ + sweepWidth_*lfo(lfoPhase_, waveform_))*inverseSampleRate_; andrewm@0: if(cph >= 1.0) andrewm@0: cph -= 1.0; andrewm@0: } andrewm@0: } andrewm@0: andrewm@0: // Having made a local copy of the state variables for each channel, now transfer the result andrewm@0: // back to the main state variable so they will be preserved for the next call of processBlock() andrewm@0: andrewm@0: carrierPhase_ = cph; andrewm@0: lfoPhase_ = lph; andrewm@0: andrewm@0: // In case we have more outputs than inputs, we'll clear any output andrewm@0: // channels that didn't contain input data, (because these aren't andrewm@0: // guaranteed to be empty - they may contain garbage). andrewm@0: for (int i = numInputChannels; i < numOutputChannels; ++i) andrewm@0: { andrewm@0: buffer.clear (i, 0, buffer.getNumSamples()); andrewm@0: } andrewm@0: } andrewm@0: andrewm@0: //============================================================================== andrewm@0: bool RingModulatorAudioProcessor::hasEditor() const andrewm@0: { andrewm@0: return true; // (change this to false if you choose to not supply an editor) andrewm@0: } andrewm@0: andrewm@0: AudioProcessorEditor* RingModulatorAudioProcessor::createEditor() andrewm@0: { andrewm@0: return new RingModulatorAudioProcessorEditor (this); andrewm@0: } andrewm@0: andrewm@0: //============================================================================== andrewm@0: void RingModulatorAudioProcessor::getStateInformation (MemoryBlock& destData) andrewm@0: { andrewm@0: // You should use this method to store your parameters in the memory block. andrewm@0: // You could do that either as raw data, or use the XML or ValueTree classes andrewm@0: // as intermediaries to make it easy to save and load complex data. andrewm@0: andrewm@0: // Create an outer XML element.. andrewm@0: XmlElement xml("C4DMPLUGINSETTINGS"); andrewm@0: andrewm@0: // add some attributes to it.. andrewm@0: xml.setAttribute("uiWidth", lastUIWidth_); andrewm@0: xml.setAttribute("uiHeight", lastUIHeight_); andrewm@0: xml.setAttribute("carrierFrequency", carrierFrequency_); andrewm@0: xml.setAttribute("sweepWidth", sweepWidth_); andrewm@0: xml.setAttribute("lfoFrequency", lfoFrequency_); andrewm@0: xml.setAttribute("waveform", waveform_); andrewm@0: andrewm@0: // then use this helper function to stuff it into the binary blob and return it.. andrewm@0: copyXmlToBinary(xml, destData); andrewm@0: } andrewm@0: andrewm@0: void RingModulatorAudioProcessor::setStateInformation (const void* data, int sizeInBytes) andrewm@0: { andrewm@0: // You should use this method to restore your parameters from this memory block, andrewm@0: // whose contents will have been created by the getStateInformation() call. andrewm@0: andrewm@0: // This getXmlFromBinary() helper function retrieves our XML from the binary blob.. andrewm@0: ScopedPointer xmlState (getXmlFromBinary (data, sizeInBytes)); andrewm@0: andrewm@0: if(xmlState != 0) andrewm@0: { andrewm@0: // make sure that it's actually our type of XML object.. andrewm@0: if(xmlState->hasTagName("C4DMPLUGINSETTINGS")) andrewm@0: { andrewm@0: // ok, now pull out our parameters.. andrewm@0: lastUIWidth_ = xmlState->getIntAttribute("uiWidth", lastUIWidth_); andrewm@0: lastUIHeight_ = xmlState->getIntAttribute("uiHeight", lastUIHeight_); andrewm@0: andrewm@0: carrierFrequency_ = (float)xmlState->getDoubleAttribute("carrierFrequency", carrierFrequency_); andrewm@0: sweepWidth_ = (float)xmlState->getDoubleAttribute("sweepWidth", sweepWidth_); andrewm@0: lfoFrequency_ = (float)xmlState->getDoubleAttribute("lfoFrequency", lfoFrequency_); andrewm@0: waveform_ = xmlState->getIntAttribute("waveform", waveform_); andrewm@0: } andrewm@0: } andrewm@0: } andrewm@0: andrewm@0: //============================================================================== andrewm@0: // Function for calculating LFO waveforms. Phase runs from 0-1, output is scaled andrewm@0: // from -1 to 1 (note: not 0 to 1 as in delay-based effects) andrewm@0: float RingModulatorAudioProcessor::lfo(float phase, int waveform) andrewm@0: { andrewm@0: switch(waveform) andrewm@0: { andrewm@0: case kWaveformTriangle: andrewm@0: if(phase < 0.25f) andrewm@0: return 4.0f*phase; andrewm@0: else if(phase < 0.75f) andrewm@0: return 1.0f - 4.0f*(phase - 0.25f); andrewm@0: else andrewm@0: return -1.0f + 4.0f*(phase - 0.75f); andrewm@0: case kWaveformSquare: andrewm@0: if(phase < 0.5f) andrewm@0: return 1.0f; andrewm@0: else andrewm@0: return -1.0f; andrewm@0: case kWaveformSawtooth: andrewm@0: if(phase < 0.5f) andrewm@0: return 2.0f*phase; andrewm@0: else andrewm@0: return 2.0f*phase - 2.0f; andrewm@0: case kWaveformInverseSawtooth: andrewm@0: if(phase < 0.5f) andrewm@0: return -2.0f*phase; andrewm@0: else andrewm@0: return 2.0f - 2.0f*phase; andrewm@0: case kWaveformSine: andrewm@0: default: andrewm@0: return sinf(2.0 * M_PI * phase); andrewm@0: } andrewm@0: } andrewm@0: andrewm@0: //============================================================================== andrewm@0: // This creates new instances of the plugin.. andrewm@0: AudioProcessor* JUCE_CALLTYPE createPluginFilter() andrewm@0: { andrewm@0: return new RingModulatorAudioProcessor(); andrewm@0: }