mt32-pi/src/synth/mt32synth.cpp

//
// mt32synth.cpp
//
// mt32-pi - A baremetal MIDI synthesizer for Raspberry Pi
// Copyright (C) 2020-2023 Dale Whinham <daleyo@gmail.com>
//
// This file is part of mt32-pi.
//
// mt32-pi is free software: you can redistribute it and/or modify it under the
// terms of the GNU General Public License as published by the Free Software
// Foundation, either version 3 of the License, or (at your option) any later
// version.
//
// mt32-pi 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 General Public License for more
// details.
//
// You should have received a copy of the GNU General Public License along with
// mt32-pi. If not, see <http://www.gnu.org/licenses/>.
//

#include <circle/logger.h>
#include <circle/timer.h>

#include "config.h"
#include "lcd/ui.h"
#include "synth/mt32synth.h"
#include "utility.h"

const char MT32SynthName[] = "mt32synth";

constexpr size_t ROMOffsetVersionStringOld  = 0x4015;
constexpr size_t ROMOffsetVersionString1_07 = 0x4011;
constexpr size_t ROMOffsetVersionStringNew  = 0x2206;
constexpr u32 MemoryAddressMIDIChannels     = 0x4000D;
constexpr u32 MemoryAddressMasterVolume     = 0x40016;

// SysEx commands for setting MIDI channel assignment (no SysEx framing, just 3-byte address and 9 channel values)
const u8 CMT32Synth::StandardMIDIChannelsSysEx[] = { 0x10, 0x00, 0x0D, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09 };
const u8 CMT32Synth::AlternateMIDIChannelsSysEx[] = { 0x10, 0x00, 0x0D, 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x09 };

CMT32Synth::CMT32Synth(unsigned nSampleRate, float nGain, float nReverbGain, TResamplerQuality ResamplerQuality)
	: CSynthBase(nSampleRate),

	  m_pSynth(nullptr),

	  m_nGain(nGain),
	  m_nReverbGain(nReverbGain),

	  m_ResamplerQuality(ResamplerQuality),
	  m_pSampleRateConverter(nullptr),

	  m_CurrentROMSet(TMT32ROMSet::Any),
	  m_pControlROMImage(nullptr),
	  m_pPCMROMImage(nullptr),

	  m_LCDTextBuffer{'\0'}
{
}

CMT32Synth::~CMT32Synth()
{
	if (m_pSynth)
		delete m_pSynth;

	if (m_pSampleRateConverter)
		delete m_pSampleRateConverter;
}

bool CMT32Synth::Initialize()
{
	if (!m_ROMManager.ScanROMs())
		return false;

	// Try to load user's preferred initial ROM set, otherwise fall back on first available
	TMT32ROMSet InitialROMSet = CConfig::Get()->MT32EmuROMSet;
	if (!m_ROMManager.HaveROMSet(InitialROMSet))
		InitialROMSet = TMT32ROMSet::Any;

	if (!m_ROMManager.GetROMSet(InitialROMSet, m_CurrentROMSet, m_pControlROMImage, m_pPCMROMImage))
		return false;

	m_pSynth = new MT32Emu::Synth(this);

	if (!m_pSynth->open(*m_pControlROMImage, *m_pPCMROMImage))
		return false;

	m_pSynth->setOutputGain(m_nGain);
	m_pSynth->setReverbOutputGain(m_nReverbGain);

	if (m_ResamplerQuality != TResamplerQuality::None)
	{
		auto quality = MT32Emu::SamplerateConversionQuality_GOOD;
		switch (m_ResamplerQuality)
		{
			case TResamplerQuality::Fastest:
				quality = MT32Emu::SamplerateConversionQuality_FASTEST;
				break;

			case TResamplerQuality::Fast:
				quality = MT32Emu::SamplerateConversionQuality_FAST;
				break;

			case TResamplerQuality::Good:
				quality = MT32Emu::SamplerateConversionQuality_GOOD;
				break;

			case TResamplerQuality::Best:
				quality = MT32Emu::SamplerateConversionQuality_BEST;
				break;

			default:
				break;
		}

		m_pSampleRateConverter = new MT32Emu::SampleRateConverter(*m_pSynth, m_nSampleRate, quality);
	}

	return true;
}

void CMT32Synth::HandleMIDIShortMessage(u32 nMessage)
{
	m_pSynth->playMsg(nMessage);

	// Update MIDI monitor
	CSynthBase::HandleMIDIShortMessage(nMessage);
}

void CMT32Synth::HandleMIDISysExMessage(const u8* pData, size_t nSize)
{
	m_pSynth->playSysex(pData, nSize);
}

void CMT32Synth::AllSoundOff()
{
	// Stop all sound immediately; mt32emu treats CC 0x7C like "All Sound Off", ignoring pedal
	for (uint8_t i = 0; i < 8; ++i)
		m_pSynth->playMsgOnPart(i, 0x0B, 0x7C, 0);

	// Reset MIDI monitor
	CSynthBase::AllSoundOff();
}

void CMT32Synth::SetMasterVolume(u8 nVolume)
{
	const u8 SetVolumeSysEx[] = { 0x10, 0x00, 0x16, nVolume };
	m_pSynth->writeSysex(0x10, SetVolumeSysEx, sizeof(SetVolumeSysEx));
}

size_t CMT32Synth::Render(s16* pOutBuffer, size_t nFrames)
{
	m_Lock.Acquire();
	if (m_pSampleRateConverter)
		m_pSampleRateConverter->getOutputSamples(pOutBuffer, nFrames);
	else
		m_pSynth->render(pOutBuffer, nFrames);
	m_Lock.Release();

	return nFrames;
}

size_t CMT32Synth::Render(float* pOutBuffer, size_t nFrames)
{
	m_Lock.Acquire();
	if (m_pSampleRateConverter)
		m_pSampleRateConverter->getOutputSamples(pOutBuffer, nFrames);
	else
		m_pSynth->render(pOutBuffer, nFrames);
	m_Lock.Release();

	return nFrames;
}

void CMT32Synth::ReportStatus() const
{
	if (m_pUI)
		m_pUI->ShowSystemMessage(GetControlROMName());
}

void CMT32Synth::UpdateLCD(CLCD& LCD, unsigned int nTicks)
{
	bool bNarrowPartStateText = false;

	const u8 nWidth = LCD.Width();
	const u8 nHeight = LCD.Height();
	u8 nStatusRow, nBarHeight;

	if (LCD.GetType() == CLCD::TType::Character)
	{
		nStatusRow = nHeight - 1;
		nBarHeight = nHeight - 1;

		// For 16-character wide LCDs
		if (nWidth < 20)
			bNarrowPartStateText = true;
	}
	else
	{
		nStatusRow = nHeight / 16 - 1;
		nBarHeight = nHeight - 16;
	}

	float PartLevels[9], PartPeaks[9];
	GetPartLevels(nTicks, PartLevels, PartPeaks);
	CUserInterface::DrawChannelLevels(LCD, nBarHeight, PartLevels, PartPeaks, 9, false);

	m_pSynth->getDisplayState(m_LCDTextBuffer, bNarrowPartStateText);

	// Remap active part indicator character
	for (size_t i = 0; i < Utility::ArraySize(m_LCDTextBuffer) - 1; ++i)
		if (m_LCDTextBuffer[i] == 1)
			m_LCDTextBuffer[i] = '\xFF';

	LCD.Print(m_LCDTextBuffer, 0, nStatusRow, true, false);
}

void CMT32Synth::SetMIDIChannels(TMIDIChannels Channels)
{
	if (Channels == TMIDIChannels::Standard)
		m_pSynth->writeSysex(0x10, StandardMIDIChannelsSysEx, sizeof(StandardMIDIChannelsSysEx));
	else
		m_pSynth->writeSysex(0x10, AlternateMIDIChannelsSysEx, sizeof(AlternateMIDIChannelsSysEx));
}

bool CMT32Synth::SwitchROMSet(TMT32ROMSet ROMSet)
{
	const MT32Emu::ROMImage* pControlROMImage;
	const MT32Emu::ROMImage* pPCMROMImage;

	// Is this ROM set already active?
	if (ROMSet == m_CurrentROMSet)
	{
		if (m_pUI)
			m_pUI->ShowSystemMessage("Already selected!");
		return false;
	}

	// Get ROM set if available
	if (!m_ROMManager.GetROMSet(ROMSet, m_CurrentROMSet, pControlROMImage, pPCMROMImage))
	{
		if (m_pUI)
			m_pUI->ShowSystemMessage("ROM set not avail!");
		return false;
	}

	// Reopen synth with new ROMs
	m_Lock.Acquire();
	m_pSynth->close();
	assert(m_pSynth->open(*pControlROMImage, *pPCMROMImage));
	m_pSynth->setOutputGain(m_nGain);
	m_pSynth->setReverbOutputGain(m_nReverbGain);
	m_Lock.Release();

	m_pControlROMImage = pControlROMImage;
	m_pPCMROMImage     = pPCMROMImage;

	return true;
}

TMT32ROMSet CMT32Synth::GetROMSet() const
{
	return m_CurrentROMSet;
}

bool CMT32Synth::NextROMSet()
{
	const u8 nCurrentROMSetIndex = static_cast<u8>(m_CurrentROMSet);
	u8 nNextROMSetIndex = (static_cast<u8>(m_CurrentROMSet) + 1) % 3;

	// Find the next available ROM set
	while (nNextROMSetIndex != nCurrentROMSetIndex && !m_ROMManager.HaveROMSet(static_cast<TMT32ROMSet>(nNextROMSetIndex)))
		nNextROMSetIndex = (nNextROMSetIndex + 1) % 3;

	if (nNextROMSetIndex == nCurrentROMSetIndex)
	{
		if (m_pUI)
			m_pUI->ShowSystemMessage("No other ROM sets!");
		return false;
	}

	return SwitchROMSet(static_cast<TMT32ROMSet>(nNextROMSetIndex));
}

const char* CMT32Synth::GetControlROMName() const
{
	// +5 to skip 'ctrl_'
	const char* pShortName = m_pControlROMImage->getROMInfo()->shortName + 5;
	const MT32Emu::Bit8u* pROMData = m_pControlROMImage->getFile()->getData();
	size_t nOffset;

	// Find version strings from ROMs
	// FIXME: Missing offset for CM-32LN ROM
	if (strstr(pShortName, "cm32l") || strstr(pShortName, "2_04") || strstr(pShortName, "2_06") || strstr(pShortName, "2_07"))
		nOffset = ROMOffsetVersionStringNew;
	else if (strstr(pShortName, "1_07") || strstr(pShortName, "bluer"))
		nOffset = ROMOffsetVersionString1_07;
	else
		nOffset = ROMOffsetVersionStringOld;

	return reinterpret_cast<const char*>(pROMData + nOffset);
}

u8 CMT32Synth::GetMasterVolume() const
{
	u8 nVolume;
	m_pSynth->readMemory(MemoryAddressMasterVolume, 1, &nVolume);
	return nVolume;
}

void CMT32Synth::GetPartLevels(unsigned int nTicks, float PartLevels[9], float PartPeaks[9])
{
	float ChannelLevels[16], ChannelPeaks[16];
	u8 MIDIChannelPartMap[9];
	u16 nPercussionMask;

	// Find which MIDI channels each MT-32 part is mapped to and identify percussion channel
	m_pSynth->readMemory(MemoryAddressMIDIChannels, 9, MIDIChannelPartMap);
	nPercussionMask = 1 << MIDIChannelPartMap[8];

	// Map channel levels to part levels
	m_MIDIMonitor.GetChannelLevels(nTicks, ChannelLevels, ChannelPeaks, nPercussionMask);
	for (u8 nPart = 0; nPart < 9; ++nPart)
	{
		const u8 nChannel = MIDIChannelPartMap[nPart];
		PartLevels[nPart] = ChannelLevels[nChannel];
		PartPeaks[nPart] = ChannelPeaks[nChannel];
	}
}

bool CMT32Synth::onMIDIQueueOverflow()
{
	CLogger::Get()->Write(MT32SynthName, LogError, "MIDI queue overflow");
	return false;
}

void CMT32Synth::printDebug(const char* pFmt, va_list pList)
{
	//CLogger::Get()->WriteV(MT32SynthName, LogDebug, pFmt, pList);
}

void CMT32Synth::showLCDMessage(const char* pMessage)
{
	CLogger::Get()->Write(MT32SynthName, LogNotice, "LCD: %s", pMessage);
}

void CMT32Synth::onDeviceReset()
{
	CLogger::Get()->Write(MT32SynthName, LogDebug, "MT-32 reset");
	m_MIDIMonitor.AllNotesOff();
	m_MIDIMonitor.ResetControllers(false);
}