/***************************************************************************
 *                                                                         *
 *   LinuxSampler - modular, streaming capable sampler                     *
 *                                                                         *
 *   Copyright (C) 2003 by Benno Senoner and Christian Schoenebeck         *
 *                                                                         *
 *   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.                                   *
 *                                                                         *
 *   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 General Public License for more details.                          *
 *                                                                         *
 *   You should have received a copy of the GNU General Public License     *
 *   along with this program; if not, write to the Free Software           *
 *   Foundation, Inc., 59 Temple Place, Suite 330, Boston,                 *
 *   MA  02111-1307  USA                                                   *
 ***************************************************************************/

#ifndef __EG_D_H__
#define __EG_D_H__

#include "global.h"
#include "modulationsystem.h"

/**
 * Decay Envelope Generator
 *
 * Simple Envelope Generator with only one stage: 'Decay'. We currently use
 * this specific EG only for pitch and thus it's not generalized yet, means
 * the initial envelope level (given by 'Depth') will raise / drop in
 * 'DecayTime' seconds to a level of exactly 1.0. If the initial level
 * ('Depth') is already 1.0, nothing happens. Beside that, the EG just
 * multiplies it's levels to the synthesis parameter sequence.
 */
class EG_D {
    public:
        EG_D(ModulationSystem::destination_t ModulationDestination);
        void Process(uint Samples);
        void Trigger(float Depth, double DecayTime, uint Delay);
    protected:
        ModulationSystem::destination_t ModulationDestination;
        uint    TriggerDelay;    ///< number of sample points triggering should be delayed
        float   Level;
        float   DecayCoeff;
        long    DecayStepsLeft;

        inline long Min(long A, long B) {
            return (A > B) ? B : A;
        }
};

#endif // __EG_D_H__