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Diffstat (limited to 'src/com/jsyn/unitgen/GrainFarm.java')
| -rw-r--r-- | src/com/jsyn/unitgen/GrainFarm.java | 176 |
1 files changed, 176 insertions, 0 deletions
diff --git a/src/com/jsyn/unitgen/GrainFarm.java b/src/com/jsyn/unitgen/GrainFarm.java new file mode 100644 index 0000000..7cff6f1 --- /dev/null +++ b/src/com/jsyn/unitgen/GrainFarm.java @@ -0,0 +1,176 @@ +/* + * Copyright 2011 Phil Burk, Mobileer Inc + * + * Licensed under the Apache License, Version 2.0 (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ + +package com.jsyn.unitgen; + +import com.jsyn.ports.UnitInputPort; +import com.jsyn.ports.UnitOutputPort; +import com.jsyn.util.PseudoRandom; + +/** + * A unit generator that generates a cloud of sound using multiple Grains. Special thanks to my + * friend Ross Bencina for his excellent article on Granular Synthesis. Several of his ideas are + * reflected in this architecture. "Implementing Real-Time Granular Synthesis" by Ross Bencina, + * Audio Anecdotes III, 2001. <code><pre> + synth.add( sampleGrainFarm = new GrainFarm() ); + grainFarm.allocate( NUM_GRAINS ); +</pre><code> + * + * @author Phil Burk (C) 2011 Mobileer Inc + * @see Grain + * @see GrainSourceSine + * @see RaisedCosineEnvelope + */ +public class GrainFarm extends UnitGenerator implements UnitSource { + /** A scaler for playback rate. Nominally 1.0. */ + public UnitInputPort rate; + public UnitInputPort rateRange; + public UnitInputPort amplitude; + public UnitInputPort amplitudeRange; + public UnitInputPort density; + public UnitInputPort duration; + public UnitInputPort durationRange; + public UnitOutputPort output; + + PseudoRandom randomizer; + private GrainState[] states; + private double countScaler = 1.0; + private GrainScheduler scheduler = new StochasticGrainScheduler(); + + public GrainFarm() { + randomizer = new PseudoRandom(); + addPort(rate = new UnitInputPort("Rate", 1.0)); + addPort(amplitude = new UnitInputPort("Amplitude", 1.0)); + addPort(duration = new UnitInputPort("Duration", 0.01)); + addPort(rateRange = new UnitInputPort("RateRange", 0.0)); + addPort(amplitudeRange = new UnitInputPort("AmplitudeRange", 0.0)); + addPort(durationRange = new UnitInputPort("DurationRange", 0.0)); + addPort(density = new UnitInputPort("Density", 0.1)); + addPort(output = new UnitOutputPort()); + } + + private class GrainState { + Grain grain; + int countdown; + double lastDuration; + final static int STATE_IDLE = 0; + final static int STATE_GAP = 1; + final static int STATE_RUNNING = 2; + int state = STATE_IDLE; + private double gapError; + + public double next(int i) { + double output = 0.0; + if (state == STATE_RUNNING) { + if (grain.hasMoreValues()) { + output = grain.next(); + } else { + startGap(i); + } + } else if (state == STATE_GAP) { + if (countdown > 0) { + countdown -= 1; + } else if (countdown == 0) { + state = STATE_RUNNING; + grain.reset(); + + setupGrain(grain, i); + + double dur = nextDuration(i); + grain.setDuration(dur); + } + } else if (state == STATE_IDLE) { + nextDuration(i); // initialize lastDuration + startGap(i); + } + return output; + } + + private double nextDuration(int i) { + double dur = duration.getValues()[i]; + dur = scheduler.nextDuration(dur); + lastDuration = dur; + return dur; + } + + private void startGap(int i) { + state = STATE_GAP; + double dens = density.getValues()[i]; + double gap = scheduler.nextGap(lastDuration, dens) * getFrameRate(); + gap += gapError; + countdown = (int) gap; + gapError = gap - countdown; + } + } + + public void setGrainArray(Grain[] grains) { + countScaler = 1.0 / grains.length; + states = new GrainState[grains.length]; + for (int i = 0; i < states.length; i++) { + states[i] = new GrainState(); + states[i].grain = grains[i]; + grains[i].setFrameRate(getSynthesisEngine().getFrameRate()); + } + } + + public void setupGrain(Grain grain, int i) { + double temp = rate.getValues()[i] * calculateOctaveScaler(rateRange.getValues()[i]); + grain.setRate(temp); + + // Scale the amplitude range so that we never go above + // original amplitude. + double base = amplitude.getValues()[i]; + double offset = base * Math.random() * amplitudeRange.getValues()[i]; + grain.setAmplitude(base - offset); + } + + public void allocate(int numGrains) { + Grain[] grainArray = new Grain[numGrains]; + for (int i = 0; i < numGrains; i++) { + Grain grain = new Grain(new GrainSourceSine(), new RaisedCosineEnvelope()); + grainArray[i] = grain; + } + setGrainArray(grainArray); + } + + @Override + public UnitOutputPort getOutput() { + return output; + } + + private double calculateOctaveScaler(double rangeValue) { + double octaveRange = 0.5 * randomizer.nextRandomDouble() * rangeValue; + return Math.pow(2.0, octaveRange); + } + + @Override + public void generate(int start, int limit) { + double[] outputs = output.getValues(); + double[] amplitudes = amplitude.getValues(); + // double frp = getSynthesisEngine().getFramePeriod(); + for (int i = start; i < limit; i++) { + double result = 0.0; + + // Mix the grains together. + for (GrainState grainState : states) { + result += grainState.next(i); + } + + outputs[i] = result * amplitudes[i] * countScaler; + } + + } +} |