view src/samer/units/Wavetable.java @ 0:bf79fb79ee13

Initial Mercurial check in.

/*
 *	Copyright (c) 2000, Samer Abdallah, King's College London.
 *	All rights reserved.
 *
 *	This software is provided AS iS and WITHOUT ANY WARRANTY; 
 *	without even the implied warranty of MERCHANTABILITY or 
 *	FITNESS FOR A PARTICULAR PURPOSE.
 */

package samer.units;
import  samer.core.*;
import  samer.maths.*;
import  samer.maths.random.*;

/**
	Periodic generator: generates periodic signal from
	a wave table
 */

public class Wavetable implements Generator
{
	int		start, end, j;
	Vec		vec;
	double [] pp;

	public Wavetable(Vec vec) {
		this(vec,0,vec.size());
	}

	public Wavetable(Vec vec, int start, int end) 
	{ 
		this.vec   = vec;
		this.start = start;
		this.end   = end;
		pp = vec.array();
		j = start;
	}

	public int  period() { return end-start; }
	public void dispose() {}
	public double next() 
	{ 
		double r=pp[j++]; 
		if (j>=end) j=start; 
		return r; 
	}

	public void next(double [] x) 
	{ 
		int	remaining=x.length;
		int	iput=0;

		while (remaining>0) {
			int avail = end-j;
			int block = remaining > avail ? avail : remaining;

			System.arraycopy( pp, j, x,iput, block);
			j+=block; iput+=block; remaining-=block;
			if (j>=end) j=start;
		}
	}

	public String toString() { return "wavetable"; }
}