src/mt32/TVA.h

/* Copyright (C) 2003, 2004, 2005, 2006, 2008, 2009 Dean Beeler, Jerome Fisher
 * Copyright (C) 2011, 2012, 2013 Dean Beeler, Jerome Fisher, Sergey V. Mikayev
 *
 *  This program is free software: you can redistribute it and/or modify
 *  it under the terms of the GNU Lesser General Public License as published by
 *  the Free Software Foundation, either version 2.1 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 Lesser General Public License for more details.
 *
 *  You should have received a copy of the GNU Lesser General Public License
 *  along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

#ifndef MT32EMU_TVA_H
#define MT32EMU_TVA_H

namespace MT32Emu {

class Part;

// Note that when entering nextPhase(), newPhase is set to phase + 1, and the descriptions/names below refer to
// newPhase's value.
enum {
        // In this phase, the base amp (as calculated in calcBasicAmp()) is targeted with an instant time.
        // This phase is entered by reset() only if time[0] != 0.
        TVA_PHASE_BASIC = 0,

        // In this phase, level[0] is targeted within time[0], and velocity potentially affects time
        TVA_PHASE_ATTACK = 1,

        // In this phase, level[1] is targeted within time[1]
        TVA_PHASE_2 = 2,

        // In this phase, level[2] is targeted within time[2]
        TVA_PHASE_3 = 3,

        // In this phase, level[3] is targeted within time[3]
        TVA_PHASE_4 = 4,

        // In this phase, immediately goes to PHASE_RELEASE unless the poly is set to sustain.
        // Aborts the partial if level[3] is 0.
        // Otherwise level[3] is continued, no phase change will occur until some external influence (like pedal release)
        TVA_PHASE_SUSTAIN = 5,

        // In this phase, 0 is targeted within time[4] (the time calculation is quite different from the other phases)
        TVA_PHASE_RELEASE = 6,

        // It's PHASE_DEAD, Jim.
        TVA_PHASE_DEAD = 7
};

class TVA {
private:
        const Partial * const partial;
        LA32Ramp *ampRamp;
        const MemParams::System * const system;

        const Part *part;
        const TimbreParam::PartialParam *partialParam;
        const MemParams::PatchTemp *patchTemp;
        const MemParams::RhythmTemp *rhythmTemp;

        bool playing = false;

        int biasAmpSubtraction = 0;
        int veloAmpSubtraction = 0;
        int keyTimeSubtraction = 0;

        Bit8u target = 0;
        int phase;

        void startRamp(Bit8u newTarget, Bit8u newIncrement, int newPhase);
        void end(int newPhase);
        void nextPhase();

public:
        TVA(const Partial *usePartial, LA32Ramp *useAmpRamp);
        void reset(const Part *newPart, const TimbreParam::PartialParam *newPartialParam, const MemParams::RhythmTemp *newRhythmTemp);
        void handleInterrupt();
        void recalcSustain();
        void startDecay();
        void startAbort();

        bool isPlaying() const;
        int getPhase() const;

        void saveState( std::ostream &stream );
        void loadState( std::istream &stream );

        // savestate debugging
        void rawVerifyState( char *name, Synth *synth );
};

}

#endif /* TVA_H_ */