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Diffstat (limited to 'audio/softsynth/mt32/AReverbModel.cpp')
| -rw-r--r-- | audio/softsynth/mt32/AReverbModel.cpp | 277 | 
1 files changed, 0 insertions, 277 deletions
diff --git a/audio/softsynth/mt32/AReverbModel.cpp b/audio/softsynth/mt32/AReverbModel.cpp deleted file mode 100644 index 1d63832157..0000000000 --- a/audio/softsynth/mt32/AReverbModel.cpp +++ /dev/null @@ -1,277 +0,0 @@ -/* 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 "mt32emu.h" - -#if MT32EMU_USE_REVERBMODEL == 1 - -#include "AReverbModel.h" - -// Analysing of state of reverb RAM address lines gives exact sizes of the buffers of filters used. This also indicates that -// the reverb model implemented in the real devices consists of three series allpass filters preceded by a non-feedback comb (or a delay with a LPF) -// and followed by three parallel comb filters - -namespace MT32Emu { - -// Because LA-32 chip makes it's output available to process by the Boss chip with a significant delay, -// the Boss chip puts to the buffer the LA32 dry output when it is ready and performs processing of the _previously_ latched data. -// Of course, the right way would be to use a dedicated variable for this, but our reverb model is way higher level, -// so we can simply increase the input buffer size. -static const Bit32u PROCESS_DELAY = 1; - -// Default reverb settings for modes 0-2. These correspond to CM-32L / LAPC-I "new" reverb settings. MT-32 reverb is a bit different. -// Found by tracing reverb RAM data lines (thanks go to Lord_Nightmare & balrog). - -static const Bit32u NUM_ALLPASSES = 3; -static const Bit32u NUM_COMBS = 4; // Well, actually there are 3 comb filters, but the entrance LPF + delay can be perfectly processed via a comb here. - -static const Bit32u MODE_0_ALLPASSES[] = {994, 729, 78}; -static const Bit32u MODE_0_COMBS[] = {705 + PROCESS_DELAY, 2349, 2839, 3632}; -static const Bit32u MODE_0_OUTL[] = {2349, 141, 1960}; -static const Bit32u MODE_0_OUTR[] = {1174, 1570, 145}; -static const Bit32u MODE_0_COMB_FACTOR[] = {0x3C, 0x60, 0x60, 0x60}; -static const Bit32u MODE_0_COMB_FEEDBACK[] = {0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, -                                              0x28, 0x48, 0x60, 0x78, 0x80, 0x88, 0x90, 0x98, -                                              0x28, 0x48, 0x60, 0x78, 0x80, 0x88, 0x90, 0x98, -                                              0x28, 0x48, 0x60, 0x78, 0x80, 0x88, 0x90, 0x98}; -static const Bit32u MODE_0_LEVELS[] = {10*1, 10*3, 10*5, 10*7, 11*9, 11*12, 11*15, 13*15}; -static const Bit32u MODE_0_LPF_AMP = 6; - -static const Bit32u MODE_1_ALLPASSES[] = {1324, 809, 176}; -static const Bit32u MODE_1_COMBS[] = {961 + PROCESS_DELAY, 2619, 3545, 4519}; -static const Bit32u MODE_1_OUTL[] = {2618, 1760, 4518}; -static const Bit32u MODE_1_OUTR[] = {1300, 3532, 2274}; -static const Bit32u MODE_1_COMB_FACTOR[] = {0x30, 0x60, 0x60, 0x60}; -static const Bit32u MODE_1_COMB_FEEDBACK[] = {0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, -											  0x28, 0x48, 0x60, 0x70, 0x78, 0x80, 0x90, 0x98, -											  0x28, 0x48, 0x60, 0x78, 0x80, 0x88, 0x90, 0x98, -											  0x28, 0x48, 0x60, 0x78, 0x80, 0x88, 0x90, 0x98}; -static const Bit32u MODE_1_LEVELS[] = {10*1, 10*3, 11*5, 11*7, 11*9, 11*12, 11*15, 14*15}; -static const Bit32u MODE_1_LPF_AMP = 6; - -static const Bit32u MODE_2_ALLPASSES[] = {969, 644, 157}; -static const Bit32u MODE_2_COMBS[] = {116 + PROCESS_DELAY, 2259, 2839, 3539}; -static const Bit32u MODE_2_OUTL[] = {2259, 718, 1769}; -static const Bit32u MODE_2_OUTR[] = {1136, 2128, 1}; -static const Bit32u MODE_2_COMB_FACTOR[] = {0, 0x20, 0x20, 0x20}; -static const Bit32u MODE_2_COMB_FEEDBACK[] = {0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, -                                              0x30, 0x58, 0x78, 0x88, 0xA0, 0xB8, 0xC0, 0xD0, -                                              0x30, 0x58, 0x78, 0x88, 0xA0, 0xB8, 0xC0, 0xD0, -                                              0x30, 0x58, 0x78, 0x88, 0xA0, 0xB8, 0xC0, 0xD0}; -static const Bit32u MODE_2_LEVELS[] = {10*1, 10*3, 11*5, 11*7, 11*9, 11*12, 12*15, 14*15}; -static const Bit32u MODE_2_LPF_AMP = 8; - -static const AReverbSettings REVERB_MODE_0_SETTINGS = {MODE_0_ALLPASSES, MODE_0_COMBS, MODE_0_OUTL, MODE_0_OUTR, MODE_0_COMB_FACTOR, MODE_0_COMB_FEEDBACK, MODE_0_LEVELS, MODE_0_LPF_AMP}; -static const AReverbSettings REVERB_MODE_1_SETTINGS = {MODE_1_ALLPASSES, MODE_1_COMBS, MODE_1_OUTL, MODE_1_OUTR, MODE_1_COMB_FACTOR, MODE_1_COMB_FEEDBACK, MODE_1_LEVELS, MODE_1_LPF_AMP}; -static const AReverbSettings REVERB_MODE_2_SETTINGS = {MODE_2_ALLPASSES, MODE_2_COMBS, MODE_2_OUTL, MODE_2_OUTR, MODE_2_COMB_FACTOR, MODE_2_COMB_FEEDBACK, MODE_2_LEVELS, MODE_2_LPF_AMP}; - -static const AReverbSettings * const REVERB_SETTINGS[] = {&REVERB_MODE_0_SETTINGS, &REVERB_MODE_1_SETTINGS, &REVERB_MODE_2_SETTINGS, &REVERB_MODE_0_SETTINGS}; - -RingBuffer::RingBuffer(const Bit32u newsize) : size(newsize), index(0) { -	buffer = new float[size]; -} - -RingBuffer::~RingBuffer() { -	delete[] buffer; -	buffer = NULL; -} - -float RingBuffer::next() { -	if (++index >= size) { -		index = 0; -	} -	return buffer[index]; -} - -bool RingBuffer::isEmpty() const { -	if (buffer == NULL) return true; - -	float *buf = buffer; -	float max = 0.001f; -	for (Bit32u i = 0; i < size; i++) { -		if ((*buf < -max) || (*buf > max)) return false; -		buf++; -	} -	return true; -} - -void RingBuffer::mute() { -	float *buf = buffer; -	for (Bit32u i = 0; i < size; i++) { -		*buf++ = 0; -	} -} - -AllpassFilter::AllpassFilter(const Bit32u useSize) : RingBuffer(useSize) {} - -float AllpassFilter::process(const float in) { -	// This model corresponds to the allpass filter implementation of the real CM-32L device -	// found from sample analysis - -	const float bufferOut = next(); - -	// store input - feedback / 2 -	buffer[index] = in - 0.5f * bufferOut; - -	// return buffer output + feedforward / 2 -	return bufferOut + 0.5f * buffer[index]; -} - -CombFilter::CombFilter(const Bit32u useSize) : RingBuffer(useSize) {} - -void CombFilter::process(const float in) { -	// This model corresponds to the comb filter implementation of the real CM-32L device -	// found from sample analysis - -	// the previously stored value -	float last = buffer[index]; - -	// prepare input + feedback -	float filterIn = in + next() * feedbackFactor; - -	// store input + feedback processed by a low-pass filter -	buffer[index] = filterFactor * last - filterIn; -} - -float CombFilter::getOutputAt(const Bit32u outIndex) const { -	return buffer[(size + index - outIndex) % size]; -} - -void CombFilter::setFeedbackFactor(const float useFeedbackFactor) { -	feedbackFactor = useFeedbackFactor; -} - -void CombFilter::setFilterFactor(const float useFilterFactor) { -	filterFactor = useFilterFactor; -} - -AReverbModel::AReverbModel(const ReverbMode mode) : allpasses(NULL), combs(NULL), currentSettings(*REVERB_SETTINGS[mode]) {} - -AReverbModel::~AReverbModel() { -	close(); -} - -void AReverbModel::open() { -	allpasses = new AllpassFilter*[NUM_ALLPASSES]; -	for (Bit32u i = 0; i < NUM_ALLPASSES; i++) { -		allpasses[i] = new AllpassFilter(currentSettings.allpassSizes[i]); -	} -	combs = new CombFilter*[NUM_COMBS]; -	for (Bit32u i = 0; i < NUM_COMBS; i++) { -		combs[i] = new CombFilter(currentSettings.combSizes[i]); -		combs[i]->setFilterFactor(currentSettings.filterFactor[i] / 256.0f); -	} -	lpfAmp = currentSettings.lpfAmp / 16.0f; -	mute(); -} - -void AReverbModel::close() { -	if (allpasses != NULL) { -		for (Bit32u i = 0; i < NUM_ALLPASSES; i++) { -			if (allpasses[i] != NULL) { -				delete allpasses[i]; -				allpasses[i] = NULL; -			} -		} -		delete[] allpasses; -		allpasses = NULL; -	} -	if (combs != NULL) { -		for (Bit32u i = 0; i < NUM_COMBS; i++) { -			if (combs[i] != NULL) { -				delete combs[i]; -				combs[i] = NULL; -			} -		} -		delete[] combs; -		combs = NULL; -	} -} - -void AReverbModel::mute() { -	if (allpasses == NULL || combs == NULL) return; -	for (Bit32u i = 0; i < NUM_ALLPASSES; i++) { -		allpasses[i]->mute(); -	} -	for (Bit32u i = 0; i < NUM_COMBS; i++) { -		combs[i]->mute(); -	} -} - -void AReverbModel::setParameters(Bit8u time, Bit8u level) { -// FIXME: wetLevel definitely needs ramping when changed -// Although, most games don't set reverb level during MIDI playback -	if (combs == NULL) return; -	level &= 7; -	time &= 7; -	for (Bit32u i = 0; i < NUM_COMBS; i++) { -		combs[i]->setFeedbackFactor(currentSettings.decayTimes[(i << 3) + time] / 256.0f); -	} -	wetLevel = (level == 0 && time == 0) ? 0.0f : 0.5f * lpfAmp * currentSettings.wetLevels[level] / 256.0f; -} - -bool AReverbModel::isActive() const { -	for (Bit32u i = 0; i < NUM_ALLPASSES; i++) { -		if (!allpasses[i]->isEmpty()) return true; -	} -	for (Bit32u i = 0; i < NUM_COMBS; i++) { -		if (!combs[i]->isEmpty()) return true; -	} -	return false; -} - -void AReverbModel::process(const float *inLeft, const float *inRight, float *outLeft, float *outRight, unsigned long numSamples) { -	float dry, link, outL1; - -	for (unsigned long i = 0; i < numSamples; i++) { -		dry = wetLevel * (*inLeft + *inRight); - -		// Get the last stored sample before processing in order not to loose it -		link = combs[0]->getOutputAt(currentSettings.combSizes[0] - 1); - -		combs[0]->process(-dry); - -		link = allpasses[0]->process(link); -		link = allpasses[1]->process(link); -		link = allpasses[2]->process(link); - -		// If the output position is equal to the comb size, get it now in order not to loose it -		outL1 = 1.5f * combs[1]->getOutputAt(currentSettings.outLPositions[0] - 1); - -		combs[1]->process(link); -		combs[2]->process(link); -		combs[3]->process(link); - -		link = outL1 + 1.5f * combs[2]->getOutputAt(currentSettings.outLPositions[1]); -		link += combs[3]->getOutputAt(currentSettings.outLPositions[2]); -		*outLeft = link; - -		link = 1.5f * combs[1]->getOutputAt(currentSettings.outRPositions[0]); -		link += 1.5f * combs[2]->getOutputAt(currentSettings.outRPositions[1]); -		link += combs[3]->getOutputAt(currentSettings.outRPositions[2]); -		*outRight = link; - -		inLeft++; -		inRight++; -		outLeft++; -		outRight++; -	} -} - -} - -#endif  | 
