/***************************************************************************
 *   Copyright (C) 2003-2004 by David Saxton                               *
 *   david@bluehaze.org                                                    *
 *                                                                         *
 *   This program is free software; you can redistribute it and/or modify  *
 *   it under the terms of the GNU General Public License as published by  *
 *   the Free Software Foundation; either version 2 of the License, or     *
 *   (at your option) any later version.                                   *
 ***************************************************************************/

#include "elementsignal.h"
#include <cmath>

ElementSignal::ElementSignal()
{
	m_type = ElementSignal::st_sinusoidal;
	m_time = 0.;
	m_frequency = 0.;
}

ElementSignal::~ElementSignal()
{
}

void ElementSignal::setStep(Type type, double frequency )
{
	m_type = type;
	m_frequency = frequency;
	m_omega = 2 * M_PI * m_frequency;
	m_time = 1./(4.*m_frequency);
}

double ElementSignal::advance(double delta)
{
	m_time += delta;
	if ( m_time >= 1./m_frequency ) m_time -= 1./m_frequency;
	
	switch (m_type)
	{
	case ElementSignal::st_sawtooth:
	{
		double val = (m_time * m_omega / M_PI);
		return 1 - remainder(val,2);
	}
	case ElementSignal::st_square:
		return (((int)trunc(m_time*m_omega/M_PI) & 1) == 0)?1:-1;
	case ElementSignal::st_triangular:
		// TODO Triangular signal
		return 0.;
	case ElementSignal::st_sinusoidal:
	default:
		return sin(m_time*m_omega);
	}
}



