/*
* Copyright (c) 2007 - 2008 by Damien Di Fede <ddf@compartmental.net>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU Library General Public License as published
* by the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public
* License along with this program; if not, write to the Free Software
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
package ddf.minim.signals;
/**
* A pulse wave is a square wave whose peaks and valleys are different length.
* The pulse width of a pulse wave is how wide the peaks.
*
* @author Damien Di Fede
* @see <a href="http://en.wikipedia.org/wiki/Pulse_wave">Pulse Wave</a>
*/
public class PulseWave extends Oscillator
{
private float width;
/**
* Constructs a pulse wave with the given frequency, amplitude and sample
* rate.
*
* @param frequency
* the frequency of the pulse wave
* @param amplitude
* the amplitude of the pulse wave
* @param sampleRate
* the sample rate of the pulse wave
*/
public PulseWave(float frequency, float amplitude, float sampleRate)
{
super(frequency, amplitude, sampleRate);
// duty period is 1:width
width = 2;
}
/**
* Sets the pulse width of the pulse wave.
*
* @param w
* the new pulse width, this will be constrained to [1, 30]
*/
public void setPulseWidth(float w)
{
width = w < 1 ? 1 : ( w > 30 ? 30 : w );
}
/**
* Returns the current pulse width.
*
* @return the current pulse width
*/
public float getPulseWidth()
{
return width;
}
protected float value(float step)
{
float v = 0;
if (step < 1 / (width + 1))
v = 1;
else
v = -1;
return v;
}
}