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audio/softsynth/mt32/TVA.h

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+/* Copyright (C) 2003, 2004, 2005, 2006, 2008, 2009 Dean Beeler, Jerome Fisher
+ * Copyright (C) 2011-2022 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
+
+#include "globals.h"
+#include "Types.h"
+#include "Structures.h"
+
+namespace MT32Emu {
+
+class LA32Ramp;
+class Part;
+class Partial;
+
+// 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::RhythmTemp *rhythmTemp;
+
+	bool playing;
+
+	int biasAmpSubtraction;
+	int veloAmpSubtraction;
+	int keyTimeSubtraction;
+
+	Bit8u target;
+	int phase;
+
+	void startRamp(Bit8u newTarget, Bit8u newIncrement, int newPhase);
+	void end(int newPhase);
+	void nextPhase();
+
+public:
+	TVA(const Partial *partial, LA32Ramp *ampRamp);
+	void reset(const Part *part, const TimbreParam::PartialParam *partialParam, const MemParams::RhythmTemp *rhythmTemp);
+	void handleInterrupt();
+	void recalcSustain();
+	void startDecay();
+	void startAbort();
+
+	bool isPlaying() const;
+	int getPhase() const;
+}; // class TVA
+
+} // namespace MT32Emu
+
+#endif // #ifndef MT32EMU_TVA_H