Noah MIDI instruments

// Super 3D Noah's Ark MIDI -> OPL instruments

#include <cstdio>
#include <stdint.h>
#include <cstring>

#pragma pack(1)
struct Instrument
{
    uint8_t
        mtrem, ctrem,
        mvol, cvol,
        matt, catt,
        msus, csus,
        mwav, cwav,
        feed,
        unused;
};

struct OP2Instrument
{
    uint16_t flags;
    uint8_t finetune;
    uint8_t notebase;

    struct Voice
    {
        uint8_t
            mtrem, matt, msus, mwav, mkey, mout,
            feed,
            ctrem, catt, csus, cwav, ckey, cout,
            unused;
        uint16_t baseoffset;
    } voice[2];
};
#pragma pack()

enum EInst
{
    I42DDC,
    I42DE8,
    I42DF4,
    I42E00,
    I42E0C,
    I42E18,
    I42E24,
    I42E30,
    I42E3C,
    I42E48,
    I42E54,
    I42E60,
    I42E6C,
    I42E78,

    NUM_INST
};

static const char* const EInstNames[NUM_INST] = {
    "stru_42DDC",
    "stru_42DE8",
    "stru_42DF4",
    "stru_42E00",
    "stru_42E0C",
    "stru_42E18",
    "stru_42E24",
    "stru_42E30",
    "stru_42E3C",
    "stru_42E48",
    "stru_42E54",
    "stru_42E60",
    "stru_42E6C",
    "stru_42E78"
};

static const Instrument instr[NUM_INST] = {
    {0x21,0x31,0x4F,0x00,0xF2,0xD2,0x52,0x73,0x00,0x00,0x06,0x00},
    {0x01,0x31,0x4F,0x04,0xF0,0x90,0xFF,0x0F,0x00,0x00,0x06,0x00},
    {0x31,0x22,0x10,0x04,0x83,0xF4,0x9F,0x78,0x00,0x00,0x0A,0x00},
    {0x11,0x31,0x05,0x00,0xF9,0xF1,0x25,0x34,0x00,0x00,0x0A,0x00},
    {0x31,0x61,0x1C,0x80,0x41,0x92,0x0B,0x3B,0x00,0x00,0x0E,0x00},
    {0x21,0x21,0x19,0x80,0x43,0x85,0x8C,0x2F,0x00,0x00,0x0C,0x00},
    {0x21,0x24,0x94,0x05,0xF0,0x90,0x09,0x0A,0x00,0x00,0x0A,0x00},
    {0x21,0xA2,0x83,0x8D,0x74,0x65,0x17,0x17,0x00,0x00,0x07,0x00},
    {0x01,0x01,0x00,0x00,0xFF,0xFF,0x07,0x07,0x00,0x00,0x07,0x00},
    {0x10,0x00,0x00,0x00,0xD8,0x87,0x4A,0x3C,0x00,0x00,0x00,0x00},
    {0x00,0x00,0x11,0x11,0xFA,0xFA,0xB5,0xB5,0x00,0x00,0x00,0x00},
    {0x00,0x00,0x00,0x00,0xF8,0xF8,0x88,0xB5,0x00,0x00,0x00,0x00},
    {0x15,0x20,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x01,0x00},
    {0x21,0x11,0x4C,0x00,0xF1,0xF2,0x63,0x72,0x00,0x00,0xC0,0x00}
};

#define NUM_MIDI_INST 175
static const EInst instrmap[NUM_MIDI_INST/8 + 1] = {
    I42E48, // 0 (1-7 should technically be 42DDC)

    I42E3C, // 8
    I42DE8, // 16
    I42DDC, // 24
    I42DF4, // 32
    I42DDC, // 40
    I42DDC, // 48
    I42E24, // 56
    I42E24, // 64
    I42E30, // 72
    I42DDC, // 80
    I42DDC, // 88
    I42DDC, // 96
    I42E3C, // 104
    I42E3C, // 112
    I42E3C, // 120

    I42E48, // 128
    I42E48, // 136
    I42E48, // 144
    I42E48, // 152
    I42E48, // 160
    I42E48  // 168
};

int main(int argc, char* argv[])
{
    FILE *gm = fopen("noah.OP2", "wb");

    fwrite("#OPL_II#", 1, 8, gm);

    for(unsigned int i = 0;i < NUM_MIDI_INST;++i)
    {
        const Instrument &minst = instr[instrmap[i/8]];
        OP2Instrument op2;
        memset(&op2, 0, sizeof(op2));

        op2.finetune = 0x80u;
        op2.voice[0].mtrem = minst.mtrem;
        op2.voice[0].matt = minst.matt;
        op2.voice[0].msus = minst.msus;
        op2.voice[0].mwav = minst.mwav;
        op2.voice[0].mkey = (minst.mvol&0xC0)>>6;
        op2.voice[0].mout = minst.mvol&0x3F;
        op2.voice[0].feed = minst.feed;
        op2.voice[0].ctrem = minst.ctrem;
        op2.voice[0].catt = minst.catt;
        op2.voice[0].csus = minst.csus;
        op2.voice[0].cwav = minst.cwav;
        op2.voice[0].ckey = (minst.cvol&0xC0)>>6;
        op2.voice[0].cout = minst.cvol&0x3F;
        op2.voice[0].unused = minst.unused;

        fwrite(&op2, sizeof(op2), 1, gm);
    }

    for(unsigned int i = 0;i < NUM_MIDI_INST;++i)
    {
        char name[32];
        memset(name, 0, 32);
        strcpy(name, EInstNames[instrmap[i/8]]);
        fwrite(name, 1, 32, gm);
    }

    fclose(gm);
    return 0;
}