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diff --git a/audio/softsynth/mt32/LegacyWaveGenerator.cpp b/audio/softsynth/mt32/LegacyWaveGenerator.cpp
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+++ b/audio/softsynth/mt32/LegacyWaveGenerator.cpp
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+/* 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/>.
+ */
+
+//#include <cmath>
+#include "mt32emu.h"
+#include "mmath.h"
+#include "LegacyWaveGenerator.h"
+
+#if MT32EMU_ACCURATE_WG == 1
+
+namespace MT32Emu {
+
+static const float MIDDLE_CUTOFF_VALUE = 128.0f;
+static const float RESONANCE_DECAY_THRESHOLD_CUTOFF_VALUE = 144.0f;
+static const float MAX_CUTOFF_VALUE = 240.0f;
+
+float LA32WaveGenerator::getPCMSample(unsigned int position) {
+	if (position >= pcmWaveLength) {
+		if (!pcmWaveLooped) {
+			return 0;
+		}
+		position = position % pcmWaveLength;
+	}
+	Bit16s pcmSample = pcmWaveAddress[position];
+	float sampleValue = EXP2F(((pcmSample & 32767) - 32787.0f) / 2048.0f);
+	return ((pcmSample & 32768) == 0) ? sampleValue : -sampleValue;
+}
+
+void LA32WaveGenerator::initSynth(const bool sawtoothWaveform, const Bit8u pulseWidth, const Bit8u resonance) {
+	this->sawtoothWaveform = sawtoothWaveform;
+	this->pulseWidth = pulseWidth;
+	this->resonance = resonance;
+
+	wavePos = 0.0f;
+	lastFreq = 0.0f;
+
+	pcmWaveAddress = NULL;
+	active = true;
+}
+
+void LA32WaveGenerator::initPCM(const Bit16s * const pcmWaveAddress, const Bit32u pcmWaveLength, const bool pcmWaveLooped, const bool pcmWaveInterpolated) {
+	this->pcmWaveAddress = pcmWaveAddress;
+	this->pcmWaveLength = pcmWaveLength;
+	this->pcmWaveLooped = pcmWaveLooped;
+	this->pcmWaveInterpolated = pcmWaveInterpolated;
+
+	pcmPosition = 0.0f;
+	active = true;
+}
+
+float LA32WaveGenerator::generateNextSample(const Bit32u ampVal, const Bit16u pitch, const Bit32u cutoffRampVal) {
+	if (!active) {
+		return 0.0f;
+	}
+
+	this->amp = amp;
+	this->pitch = pitch;
+
+	float sample = 0.0f;
+
+	// SEMI-CONFIRMED: From sample analysis:
+	// (1) Tested with a single partial playing PCM wave 77 with pitchCoarse 36 and no keyfollow, velocity follow, etc.
+	// This gives results within +/- 2 at the output (before any DAC bitshifting)
+	// when sustaining at levels 156 - 255 with no modifiers.
+	// (2) Tested with a special square wave partial (internal capture ID tva5) at TVA envelope levels 155-255.
+	// This gives deltas between -1 and 0 compared to the real output. Note that this special partial only produces
+	// positive amps, so negative still needs to be explored, as well as lower levels.
+	//
+	// Also still partially unconfirmed is the behaviour when ramping between levels, as well as the timing.
+
+	float amp = EXP2F(ampVal / -1024.0f / 4096.0f);
+	float freq = EXP2F(pitch / 4096.0f - 16.0f) * SAMPLE_RATE;
+
+	if (isPCMWave()) {
+		// Render PCM waveform
+		int len = pcmWaveLength;
+		int intPCMPosition = (int)pcmPosition;
+		if (intPCMPosition >= len && !pcmWaveLooped) {
+			// We're now past the end of a non-looping PCM waveform so it's time to die.
+			deactivate();
+			return 0.0f;
+		}
+		float positionDelta = freq * 2048.0f / SAMPLE_RATE;
+
+		// Linear interpolation
+		float firstSample = getPCMSample(intPCMPosition);
+		// We observe that for partial structures with ring modulation the interpolation is not applied to the slave PCM partial.
+		// It's assumed that the multiplication circuitry intended to perform the interpolation on the slave PCM partial
+		// is borrowed by the ring modulation circuit (or the LA32 chip has a similar lack of resources assigned to each partial pair).
+		if (pcmWaveInterpolated) {
+			sample = firstSample + (getPCMSample(intPCMPosition + 1) - firstSample) * (pcmPosition - intPCMPosition);
+		} else {
+			sample = firstSample;
+		}
+
+		float newPCMPosition = pcmPosition + positionDelta;
+		if (pcmWaveLooped) {
+			newPCMPosition = fmod(newPCMPosition, (float)pcmWaveLength);
+		}
+		pcmPosition = newPCMPosition;
+	} else {
+		// Render synthesised waveform
+		wavePos *= lastFreq / freq;
+		lastFreq = freq;
+
+		float resAmp = EXP2F(1.0f - (32 - resonance) / 4.0f);
+		{
+			//static const float resAmpFactor = EXP2F(-7);
+			//resAmp = EXP2I(resonance << 10) * resAmpFactor;
+		}
+
+		// The cutoffModifier may not be supposed to be directly added to the cutoff -
+		// it may for example need to be multiplied in some way.
+		// The 240 cutoffVal limit was determined via sample analysis (internal Munt capture IDs: glop3, glop4).
+		// More research is needed to be sure that this is correct, however.
+		float cutoffVal = cutoffRampVal / 262144.0f;
+		if (cutoffVal > MAX_CUTOFF_VALUE) {
+			cutoffVal = MAX_CUTOFF_VALUE;
+		}
+
+		// Wave length in samples
+		float waveLen = SAMPLE_RATE / freq;
+
+		// Init cosineLen
+		float cosineLen = 0.5f * waveLen;
+		if (cutoffVal > MIDDLE_CUTOFF_VALUE) {
+			cosineLen *= EXP2F((cutoffVal - MIDDLE_CUTOFF_VALUE) / -16.0f); // found from sample analysis
+		}
+
+		// Start playing in center of first cosine segment
+		// relWavePos is shifted by a half of cosineLen
+		float relWavePos = wavePos + 0.5f * cosineLen;
+		if (relWavePos > waveLen) {
+			relWavePos -= waveLen;
+		}
+
+		// Ratio of positive segment to wave length
+		float pulseLen = 0.5f;
+		if (pulseWidth > 128) {
+			pulseLen = EXP2F((64 - pulseWidth) / 64.0f);
+			//static const float pulseLenFactor = EXP2F(-192 / 64);
+			//pulseLen = EXP2I((256 - pulseWidthVal) << 6) * pulseLenFactor;
+		}
+		pulseLen *= waveLen;
+
+		float hLen = pulseLen - cosineLen;
+
+		// Ignore pulsewidths too high for given freq
+		if (hLen < 0.0f) {
+			hLen = 0.0f;
+		}
+
+		// Ignore pulsewidths too high for given freq and cutoff
+		float lLen = waveLen - hLen - 2 * cosineLen;
+		if (lLen < 0.0f) {
+			lLen = 0.0f;
+		}
+
+		// Correct resAmp for cutoff in range 50..66
+		if ((cutoffVal >= 128.0f) && (cutoffVal < 144.0f)) {
+			resAmp *= sin(FLOAT_PI * (cutoffVal - 128.0f) / 32.0f);
+		}
+
+		// Produce filtered square wave with 2 cosine waves on slopes
+
+		// 1st cosine segment
+		if (relWavePos < cosineLen) {
+			sample = -cos(FLOAT_PI * relWavePos / cosineLen);
+		} else
+
+		// high linear segment
+		if (relWavePos < (cosineLen + hLen)) {
+			sample = 1.f;
+		} else
+
+		// 2nd cosine segment
+		if (relWavePos < (2 * cosineLen + hLen)) {
+			sample = cos(FLOAT_PI * (relWavePos - (cosineLen + hLen)) / cosineLen);
+		} else {
+
+		// low linear segment
+			sample = -1.f;
+		}
+
+		if (cutoffVal < 128.0f) {
+
+			// Attenuate samples below cutoff 50
+			// Found by sample analysis
+			sample *= EXP2F(-0.125f * (128.0f - cutoffVal));
+		} else {
+
+			// Add resonance sine. Effective for cutoff > 50 only
+			float resSample = 1.0f;
+
+			// Resonance decay speed factor
+			float resAmpDecayFactor = Tables::getInstance().resAmpDecayFactor[resonance >> 2];
+
+			// Now relWavePos counts from the middle of first cosine
+			relWavePos = wavePos;
+
+			// negative segments
+			if (!(relWavePos < (cosineLen + hLen))) {
+				resSample = -resSample;
+				relWavePos -= cosineLen + hLen;
+
+				// From the digital captures, the decaying speed of the resonance sine is found a bit different for the positive and the negative segments
+				resAmpDecayFactor += 0.25f;
+			}
+
+			// Resonance sine WG
+			resSample *= sin(FLOAT_PI * relWavePos / cosineLen);
+
+			// Resonance sine amp
+			float resAmpFadeLog2 = -0.125f * resAmpDecayFactor * (relWavePos / cosineLen); // seems to be exact
+			float resAmpFade = EXP2F(resAmpFadeLog2);
+
+			// Now relWavePos set negative to the left from center of any cosine
+			relWavePos = wavePos;
+
+			// negative segment
+			if (!(wavePos < (waveLen - 0.5f * cosineLen))) {
+				relWavePos -= waveLen;
+			} else
+
+			// positive segment
+			if (!(wavePos < (hLen + 0.5f * cosineLen))) {
+				relWavePos -= cosineLen + hLen;
+			}
+
+			// To ensure the output wave has no breaks, two different windows are appied to the beginning and the ending of the resonance sine segment
+			if (relWavePos < 0.5f * cosineLen) {
+				float syncSine = sin(FLOAT_PI * relWavePos / cosineLen);
+				if (relWavePos < 0.0f) {
+					// The window is synchronous square sine here
+					resAmpFade *= syncSine * syncSine;
+				} else {
+					// The window is synchronous sine here
+					resAmpFade *= syncSine;
+				}
+			}
+
+			sample += resSample * resAmp * resAmpFade;
+		}
+
+		// sawtooth waves
+		if (sawtoothWaveform) {
+			sample *= cos(FLOAT_2PI * wavePos / waveLen);
+		}
+
+		wavePos++;
+
+		// wavePos isn't supposed to be > waveLen
+		if (wavePos > waveLen) {
+			wavePos -= waveLen;
+		}
+	}
+
+	// Multiply sample with current TVA value
+	sample *= amp;
+	return sample;
+}
+
+void LA32WaveGenerator::deactivate() {
+	active = false;
+}
+
+bool LA32WaveGenerator::isActive() const {
+	return active;
+}
+
+bool LA32WaveGenerator::isPCMWave() const {
+	return pcmWaveAddress != NULL;
+}
+
+void LA32PartialPair::init(const bool ringModulated, const bool mixed) {
+	this->ringModulated = ringModulated;
+	this->mixed = mixed;
+	masterOutputSample = 0.0f;
+	slaveOutputSample = 0.0f;
+}
+
+void LA32PartialPair::initSynth(const PairType useMaster, const bool sawtoothWaveform, const Bit8u pulseWidth, const Bit8u resonance) {
+	if (useMaster == MASTER) {
+		master.initSynth(sawtoothWaveform, pulseWidth, resonance);
+	} else {
+		slave.initSynth(sawtoothWaveform, pulseWidth, resonance);
+	}
+}
+
+void LA32PartialPair::initPCM(const PairType useMaster, const Bit16s *pcmWaveAddress, const Bit32u pcmWaveLength, const bool pcmWaveLooped) {
+	if (useMaster == MASTER) {
+		master.initPCM(pcmWaveAddress, pcmWaveLength, pcmWaveLooped, true);
+	} else {
+		slave.initPCM(pcmWaveAddress, pcmWaveLength, pcmWaveLooped, !ringModulated);
+	}
+}
+
+void LA32PartialPair::generateNextSample(const PairType useMaster, const Bit32u amp, const Bit16u pitch, const Bit32u cutoff) {
+	if (useMaster == MASTER) {
+		masterOutputSample = master.generateNextSample(amp, pitch, cutoff);
+	} else {
+		slaveOutputSample = slave.generateNextSample(amp, pitch, cutoff);
+	}
+}
+
+Bit16s LA32PartialPair::nextOutSample() {
+	float outputSample;
+	if (ringModulated) {
+		float ringModulatedSample = masterOutputSample * slaveOutputSample;
+		outputSample = mixed ? masterOutputSample + ringModulatedSample : ringModulatedSample;
+	} else {
+		outputSample = masterOutputSample + slaveOutputSample;
+	}
+	return Bit16s(outputSample * 8192.0f);
+}
+
+void LA32PartialPair::deactivate(const PairType useMaster) {
+	if (useMaster == MASTER) {
+		master.deactivate();
+		masterOutputSample = 0.0f;
+	} else {
+		slave.deactivate();
+		slaveOutputSample = 0.0f;
+	}
+}
+
+bool LA32PartialPair::isActive(const PairType useMaster) const {
+	return useMaster == MASTER ? master.isActive() : slave.isActive();
+}
+
+}
+
+#endif // #if MT32EMU_ACCURATE_WG == 1