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import jm.audio.AudioObject;
import jm.audio.Instrument;
import jm.audio.io.SampleOut;
import jm.audio.synth.*;

/**
 * A squarewave instrument implementation which includes
 * a low pass filter that is swept by a cosine wave.
 *
 * @author Andrew Brown
 */

public final class LFOFilteredSquareInst extends Instrument {
    //----------------------------------------------
    // Attributes
    //----------------------------------------------
    private int sampleRate;
    private int filterCutoff;
    private int channels;
    private int modAmount;

    //----------------------------------------------
    // Constructor
    //----------------------------------------------

    /**
     * Basic default constructor to set an initial sampling rate
     *
     * @param sampleRate Integer in Hertz
     */
    public LFOFilteredSquareInst(int sampleRate) {
        this(sampleRate, (int) (sampleRate * 0.2));
    }

    /**
     * Constructor that sets sample rate and filter cutoff frequency
     *
     * @param sampleRate   The number of samples per second (quality)
     * @param filterCutoff The frequency in hertz above which overtones are cut
     */
    public LFOFilteredSquareInst(int sampleRate, int filterCutoff) {
        this(sampleRate, filterCutoff, (int) (filterCutoff * 0.9));
    }

    /**
     * Constructor that sets sample rate, filter cutoff, and modulation amount
     *
     * @param sampleRate   The number of samples per second (quality)
     * @param filterCutoff The frequency above which overtones are cut
     * @param modAmount    The filter devation above and below the cutoff
     */
    public LFOFilteredSquareInst(int sampleRate, int filterCutoff, int modAmount) {
        this(sampleRate, filterCutoff, modAmount, 1);
    }

    /**
     * Constructor that sets all attributes
     *
     * @param sampleRate   The number of samples per second (quality)
     * @param filterCutoff The frequency above which overtones are cut
     * @param modAmount    The filter devation above and below the cutoff
     * @param channels     1 for Mono or 2 for Stereo
     */
    public LFOFilteredSquareInst(int sampleRate, int filterCutoff, int modAmount, int channels) {
        this.sampleRate = sampleRate;
        this.filterCutoff = filterCutoff;
        this.modAmount = modAmount;
        this.channels = channels;
    }

    //----------------------------------------------
    // Methods
    //----------------------------------------------

    /**
     * Initialisation method used to build the objects that
     * this instrument will use and specify thier interconnections.
     */
    public void createChain() {
        // oscilators
        Oscillator osc = new Oscillator(this, Oscillator.SQUARE_WAVE, this.sampleRate, this.channels);
        Oscillator osc2 = new Oscillator(this, Oscillator.SQUARE_WAVE, this.sampleRate, this.channels);
        osc2.setFrqRatio((float) 1.001);
        Oscillator osc3 = new Oscillator(this, Oscillator.SQUARE_WAVE, this.sampleRate, this.channels);
        osc3.setFrqRatio((float) 0.999);
        Add add = new Add(new AudioObject[]{osc, osc2, osc3});
        // filter mod
        Value modfreq = new Value(this, this.sampleRate, this.channels, (float) 0.3);
        Oscillator sineMod = new Oscillator(modfreq, Oscillator.COSINE_WAVE, Oscillator.FREQUENCY);
        sineMod.setAmp((float) this.modAmount);
        // Filter - try changing this to a high pass filter
        Filter filt = new Filter(new AudioObject[]{add, sineMod}, this.filterCutoff, Filter.LOW_PASS);
        Envelope env = new Envelope(filt,
                new double[]{0.0, 0.0, 0.05, 1.0, 0.2, 0.3, 0.8, 0.2, 1.0, 0.0});
        Volume vol = new Volume(env);
        SampleOut sout = new SampleOut(vol);
    }
}