scummvm/audio/softsynth/mt32/Poly.cpp

/* Copyright (C) 2003, 2004, 2005, 2006, 2008, 2009 Dean Beeler, Jerome Fisher
 * Copyright (C) 2011-2021 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/>.
 */

#include <cstddef>

#include "internals.h"

#include "Poly.h"
#include "Part.h"
#include "Partial.h"
#include "Synth.h"

namespace MT32Emu {

Poly::Poly() {
	part = NULL;
	key = 255;
	velocity = 255;
	sustain = false;
	activePartialCount = 0;
	for (int i = 0; i < 4; i++) {
		partials[i] = NULL;
	}
	state = POLY_Inactive;
	next = NULL;
}

void Poly::setPart(Part *usePart) {
	part = usePart;
}

void Poly::reset(unsigned int newKey, unsigned int newVelocity, bool newSustain, Partial **newPartials) {
	if (isActive()) {
		// This should never happen
		part->getSynth()->printDebug("Resetting active poly. Active partial count: %i\n", activePartialCount);
		for (int i = 0; i < 4; i++) {
			if (partials[i] != NULL && partials[i]->isActive()) {
				partials[i]->deactivate();
				activePartialCount--;
			}
		}
		state = POLY_Inactive;
	}

	key = newKey;
	velocity = newVelocity;
	sustain = newSustain;

	activePartialCount = 0;
	for (int i = 0; i < 4; i++) {
		partials[i] = newPartials[i];
		if (newPartials[i] != NULL) {
			activePartialCount++;
			state = POLY_Playing;
		}
	}
}

bool Poly::noteOff(bool pedalHeld) {
	// Generally, non-sustaining instruments ignore note off. They die away eventually anyway.
	// Key 0 (only used by special cases on rhythm part) reacts to note off even if non-sustaining or pedal held.
	if (state == POLY_Inactive || state == POLY_Releasing) {
		return false;
	}
	if (pedalHeld) {
		if (state == POLY_Held) {
			return false;
		}
		state = POLY_Held;
	} else {
		startDecay();
	}
	return true;
}

bool Poly::stopPedalHold() {
	if (state != POLY_Held) {
		return false;
	}
	return startDecay();
}

bool Poly::startDecay() {
	if (state == POLY_Inactive || state == POLY_Releasing) {
		return false;
	}
	state = POLY_Releasing;

	for (int t = 0; t < 4; t++) {
		Partial *partial = partials[t];
		if (partial != NULL) {
			partial->startDecayAll();
		}
	}
	return true;
}

bool Poly::startAbort() {
	if (state == POLY_Inactive || part->getSynth()->isAbortingPoly()) {
		return false;
	}
	for (int t = 0; t < 4; t++) {
		Partial *partial = partials[t];
		if (partial != NULL) {
			partial->startAbort();
			part->getSynth()->abortingPoly = this;
		}
	}
	return true;
}

void Poly::backupCacheToPartials(PatchCache cache[4]) {
	for (int partialNum = 0; partialNum < 4; partialNum++) {
		Partial *partial = partials[partialNum];
		if (partial != NULL) {
			partial->backupCache(cache[partialNum]);
		}
	}
}

/**
 * Returns the internal key identifier.
 * For non-rhythm, this is within the range 12 to 108.
 * For rhythm on MT-32, this is 0 or 1 (special cases) or within the range 24 to 87.
 * For rhythm on devices with extended PCM sounds (e.g. CM-32L), this is 0, 1 or 24 to 108
 */
unsigned int Poly::getKey() const {
	return key;
}

unsigned int Poly::getVelocity() const {
	return velocity;
}

bool Poly::canSustain() const {
	return sustain;
}

PolyState Poly::getState() const {
	return state;
}

unsigned int Poly::getActivePartialCount() const {
	return activePartialCount;
}

bool Poly::isActive() const {
	return state != POLY_Inactive;
}

// This is called by Partial to inform the poly that the Partial has deactivated
void Poly::partialDeactivated(Partial *partial) {
	for (int i = 0; i < 4; i++) {
		if (partials[i] == partial) {
			partials[i] = NULL;
			activePartialCount--;
		}
	}
	if (activePartialCount == 0) {
		state = POLY_Inactive;
		if (part->getSynth()->abortingPoly == this) {
			part->getSynth()->abortingPoly = NULL;
		}
	}
	part->partialDeactivated(this);
}

Poly *Poly::getNext() const {
	return next;
}

void Poly::setNext(Poly *poly) {
	next = poly;
}

} // namespace MT32Emu