ref: 29c5ba092bb123e3ae0116a1586b1f583160a2a3
dir: /src/midifallback.c/
//
// Copyright(C) 2022 ceski
//
// This program 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 2
// 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 General Public License for more details.
//
// DESCRIPTION:
// MIDI instrument fallback support
//
#ifdef _WIN32
#include "doomtype.h"
#include "midifile.h"
#include "midifallback.h"
static const byte drums_table[128] = {
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08,
0x10, 0x10, 0x10, 0x10, 0x10, 0x10, 0x10, 0x10,
0x18, 0x19, 0x18, 0x18, 0x18, 0x18, 0x18, 0x18,
0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20,
0x28, 0x28, 0x28, 0x28, 0x28, 0x28, 0x28, 0x28,
0x30, 0x30, 0x30, 0x30, 0x30, 0x30, 0x30, 0x30,
0x38, 0x38, 0x38, 0x38, 0x38, 0x38, 0x38, 0x38,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x7F
};
static byte variation[128][128];
static byte bank_msb[MIDI_CHANNELS_PER_TRACK];
static byte drum_map[MIDI_CHANNELS_PER_TRACK];
static boolean selected[MIDI_CHANNELS_PER_TRACK];
static void UpdateDrumMap(const byte *msg, unsigned int length)
{
byte idx;
byte checksum;
// GS allows drums on any channel using SysEx messages.
// The message format is F0 followed by:
//
// 41 10 42 12 40 <ch> 15 <map> <sum> F7
//
// <ch> is [11-19, 10, 1A-1F] for channels 1-16. Note the position of 10.
// <map> is 00-02 for off (normal part), drum map 1, or drum map 2.
// <sum> is checksum.
if (length == 10 &&
msg[0] == 0x41 && // Roland
msg[1] == 0x10 && // Device ID
msg[2] == 0x42 && // GS
msg[3] == 0x12 && // DT1
msg[4] == 0x40 && // Address MSB
msg[6] == 0x15 && // Address LSB
msg[9] == 0xF7) // SysEx EOX
{
checksum = 128 - ((int)msg[4] + msg[5] + msg[6] + msg[7]) % 128;
if (msg[8] != checksum)
{
return;
}
if (msg[5] == 0x10) // Channel 10
{
idx = 9;
}
else if (msg[5] < 0x1A) // Channels 1-9
{
idx = (msg[5] & 0x0F) - 1;
}
else // Channels 11-16
{
idx = msg[5] & 0x0F;
}
drum_map[idx] = msg[7];
}
}
static boolean GetProgramFallback(byte idx, byte program,
midi_fallback_t *fallback)
{
if (drum_map[idx] == 0) // Normal channel
{
if (bank_msb[idx] == 0 || variation[bank_msb[idx]][program])
{
// Found a capital or variation for this bank select MSB.
selected[idx] = true;
return false;
}
fallback->type = FALLBACK_BANK_MSB;
if (!selected[idx] || bank_msb[idx] > 63)
{
// Fall to capital when no instrument has (successfully)
// selected this variation or if the variation is above 63.
fallback->value = 0;
return true;
}
// A previous instrument used this variation but it's not
// valid for the current instrument. Fall to the next valid
// "sub-capital" (next variation that is a multiple of 8).
fallback->value = (bank_msb[idx] / 8) * 8;
while (fallback->value > 0)
{
if (variation[fallback->value][program])
{
break;
}
fallback->value -= 8;
}
return true;
}
else // Drums channel
{
if (program != drums_table[program])
{
// Use drum set from drums fallback table.
// Drums 0-63 and 127: same as original SC-55 (1.00 - 1.21).
// Drums 64-126: standard drum set (0).
fallback->type = FALLBACK_DRUMS;
fallback->value = drums_table[program];
selected[idx] = true;
return true;
}
}
return false;
}
void MIDI_CheckFallback(const midi_event_t *event, midi_fallback_t *fallback)
{
byte idx;
byte program;
switch ((int)event->event_type)
{
case MIDI_EVENT_SYSEX:
UpdateDrumMap(event->data.sysex.data, event->data.sysex.length);
break;
case MIDI_EVENT_CONTROLLER:
idx = event->data.channel.channel;
switch (event->data.channel.param1)
{
case MIDI_CONTROLLER_BANK_SELECT_MSB:
bank_msb[idx] = event->data.channel.param2;
selected[idx] = false;
break;
case MIDI_CONTROLLER_BANK_SELECT_LSB:
selected[idx] = false;
if (event->data.channel.param2 > 0)
{
// Bank select LSB > 0 not supported. This also
// preserves user's current SC-XX map.
fallback->type = FALLBACK_BANK_LSB;
fallback->value = 0;
return;
}
break;
case EMIDI_CONTROLLER_PROGRAM_CHANGE:
program = event->data.channel.param2;
if (GetProgramFallback(idx, program, fallback))
{
return;
}
break;
}
break;
case MIDI_EVENT_PROGRAM_CHANGE:
idx = event->data.channel.channel;
program = event->data.channel.param1;
if (GetProgramFallback(idx, program, fallback))
{
return;
}
break;
}
fallback->type = FALLBACK_NONE;
fallback->value = 0;
}
void MIDI_ResetFallback(void)
{
int i;
for (i = 0; i < MIDI_CHANNELS_PER_TRACK; i++)
{
bank_msb[i] = 0;
drum_map[i] = 0;
selected[i] = false;
}
// Channel 10 (index 9) is set to drum map 1 by default.
drum_map[9] = 1;
}
void MIDI_InitFallback(void)
{
byte program;
MIDI_ResetFallback();
// Capital
for (program = 0; program < 128; program++)
{
variation[0][program] = 1;
}
// Variation #1
variation[1][38] = 1;
variation[1][57] = 1;
variation[1][60] = 1;
variation[1][80] = 1;
variation[1][81] = 1;
variation[1][98] = 1;
variation[1][102] = 1;
variation[1][104] = 1;
variation[1][120] = 1;
variation[1][121] = 1;
variation[1][122] = 1;
variation[1][123] = 1;
variation[1][124] = 1;
variation[1][125] = 1;
variation[1][126] = 1;
variation[1][127] = 1;
// Variation #2
variation[2][102] = 1;
variation[2][120] = 1;
variation[2][122] = 1;
variation[2][123] = 1;
variation[2][124] = 1;
variation[2][125] = 1;
variation[2][126] = 1;
variation[2][127] = 1;
// Variation #3
variation[3][122] = 1;
variation[3][123] = 1;
variation[3][124] = 1;
variation[3][125] = 1;
variation[3][126] = 1;
variation[3][127] = 1;
// Variation #4
variation[4][122] = 1;
variation[4][124] = 1;
variation[4][125] = 1;
variation[4][126] = 1;
// Variation #5
variation[5][122] = 1;
variation[5][124] = 1;
variation[5][125] = 1;
variation[5][126] = 1;
// Variation #6
variation[6][125] = 1;
// Variation #7
variation[7][125] = 1;
// Variation #8
variation[8][0] = 1;
variation[8][1] = 1;
variation[8][2] = 1;
variation[8][3] = 1;
variation[8][4] = 1;
variation[8][5] = 1;
variation[8][6] = 1;
variation[8][11] = 1;
variation[8][12] = 1;
variation[8][14] = 1;
variation[8][16] = 1;
variation[8][17] = 1;
variation[8][19] = 1;
variation[8][21] = 1;
variation[8][24] = 1;
variation[8][25] = 1;
variation[8][26] = 1;
variation[8][27] = 1;
variation[8][28] = 1;
variation[8][30] = 1;
variation[8][31] = 1;
variation[8][38] = 1;
variation[8][39] = 1;
variation[8][40] = 1;
variation[8][48] = 1;
variation[8][50] = 1;
variation[8][61] = 1;
variation[8][62] = 1;
variation[8][63] = 1;
variation[8][80] = 1;
variation[8][81] = 1;
variation[8][107] = 1;
variation[8][115] = 1;
variation[8][116] = 1;
variation[8][117] = 1;
variation[8][118] = 1;
variation[8][125] = 1;
// Variation #9
variation[9][14] = 1;
variation[9][118] = 1;
variation[9][125] = 1;
// Variation #16
variation[16][0] = 1;
variation[16][4] = 1;
variation[16][5] = 1;
variation[16][6] = 1;
variation[16][16] = 1;
variation[16][19] = 1;
variation[16][24] = 1;
variation[16][25] = 1;
variation[16][28] = 1;
variation[16][39] = 1;
variation[16][62] = 1;
variation[16][63] = 1;
// Variation #24
variation[24][4] = 1;
variation[24][6] = 1;
// Variation #32
variation[32][16] = 1;
variation[32][17] = 1;
variation[32][24] = 1;
variation[32][52] = 1;
// CM-64 Map (PCM)
for (program = 0; program < 64; program++)
{
variation[126][program] = 1;
}
// CM-64 Map (LA)
for (program = 0; program < 128; program++)
{
variation[127][program] = 1;
}
}
#endif