ref: 5c96a51f3a0684765afd24930d2df7a899c22d70
dir: /sys/src/games/dmid.c/
#include <u.h> #include <libc.h> #include <bio.h> #include <thread.h> typedef struct Inst Inst; typedef struct Opl Opl; typedef struct Chan Chan; typedef struct Trk Trk; enum{ Rate = 49716, /* opl3 sampling rate */ Ninst = 128 + 81-35+1, Rwse = 0x01, Mwse = 1<<5, /* wave selection enable */ Rctl = 0x20, Rsca = 0x40, Mlvl = 63<<0, /* total level */ Mscl = 3<<6, /* scaling level */ Ratk = 0x60, Rsus = 0x80, Rnum = 0xa0, /* f number lsb */ Roct = 0xb0, Mmsb = 3<<0, /* f number msb */ Moct = 7<<2, Mkon = 1<<5, Rfed = 0xc0, Rwav = 0xe0, Rop3 = 0x105, }; struct Inst{ int fixed; int dbl; int fine; uchar n; uchar i[13]; uchar i2[13]; s16int base[2]; }; Inst inst[Ninst]; struct Opl{ Chan *c; int n; int midn; int blk; int v; vlong t; uchar *i; }; Opl opl[18], *ople = opl + nelem(opl); int port[] = { 0x0, 0x1, 0x2, 0x8, 0x9, 0xa, 0x10, 0x11, 0x12, 0x100, 0x101, 0x102, 0x108, 0x109, 0x10a, 0x110, 0x111, 0x112 }; int sport[] = { 0x0, 0x1, 0x2, 0x3, 0x4, 0x5, 0x6, 0x7, 0x8, 0x100, 0x101, 0x102, 0x103, 0x104, 0x105, 0x106, 0x107, 0x108 }; uchar ovol[] = { 0, 32, 48, 58, 64, 70, 74, 77, 80, 83, 86, 88, 90, 92, 93, 95, 96, 98, 99, 100, 102, 103, 104, 105, 106, 107, 108, 108, 109, 110, 111, 112, 112, 113, 114, 114, 115, 116, 116, 117, 118, 118, 119, 119, 120, 120, 121, 121, 122, 122, 123, 123, 124, 124, 124, 125, 125, 126, 126, 126, 127, 127, 127, 128, 128 }; struct Chan{ Inst *i; int v; int bend; int pan; }; Chan chan[16]; struct Trk{ u8int *s; u8int *p; u8int *e; uvlong t; int ev; }; Trk *tr; double freq[128]; int mfmt, ntrk, div = 1, tempo, opl2, stream; uvlong T; Channel *echan; Biobuf *ib, *ob; void * emalloc(ulong n) { void *p; p = mallocz(n, 1); if(p == nil) sysfatal("mallocz: %r"); setmalloctag(p, getcallerpc(&n)); return p; } Biobuf * bfdopen(int fd, int mode) { Biobuf *bf; bf = Bfdopen(fd, mode); if(bf == nil) sysfatal("bfdopen: %r"); Blethal(bf, nil); return bf; } Biobuf * bopen(char *file, int mode) { int fd; fd = open(file, mode); if(fd < 0) sysfatal("bopen: %r"); return bfdopen(fd, mode); } void bread(void *u, int n) { if(Bread(ib, u, n) != n) sysfatal("bread: short read"); } u8int get8(Trk *x) { u8int v; if(x == nil){ Bread(ib, &v, 1); return v; } if(x->p >= x->e) sysfatal("track overflow"); return *x->p++; } u16int get16(Trk *x) { u16int v; v = get8(x) << 8; return v | get8(x); } u32int get32(Trk *x) { u32int v; v = get16(x) << 16; return v | get16(x); } void putcmd(u16int r, u8int v, u16int dt) { uchar *p, u[5]; p = u; *p++ = r; if(!opl2) *p++ = r >> 8; *p++ = v; *p++ = dt; *p++ = dt >> 8; Bwrite(ob, u, p-u); } void setinst(Opl *o, uchar *i) { int p; p = sport[o - opl]; putcmd(Roct+p, o->blk, 0); putcmd(Rfed+p, i[6] & ~0x30 | o->c->pan, 0); p = port[o - opl]; putcmd(Rctl+p, i[0], 0); putcmd(Ratk+p, i[1], 0); putcmd(Rsus+p, i[2], 0); putcmd(Rwav+p, i[3] & 3, 0); putcmd(Rctl+3+p, i[7], 0); putcmd(Ratk+3+p, i[8], 0); putcmd(Rsus+3+p, i[9], 0); putcmd(Rwav+3+p, i[10] & 3, 0); o->i = i; } void noteoff(Chan *c, int n, int) { Opl *o; for(o=opl; o<ople; o++) if(o->c == c && o->midn == n){ putcmd(Roct+sport[o-opl], o->blk, 0); o->n = -1; } } Opl * getch(void) { Opl *o, *p; p = opl; for(o=opl; o<ople; o++){ if(o->n < 0) return o; if(o->t < p->t) p = o; } return p; } void setoct(Opl *o) { int n, b, f, d; double e; d = o->c->bend; d += o->i == o->c->i->i2 ? o->c->i->fine : 0; n = o->n + d / 0x1000 & 0x7f; e = freq[n] + (d % 0x1000) * (freq[n+1] - freq[n]) / 0x1000; if(o->c->i->fixed) e = (double)(int)e; f = (e * (1 << 20)) / Rate; for(b=1; b<8; b++, f>>=1) if(f < 1024) break; o->blk = b << 2 & Moct | f >> 8 & Mmsb; putcmd(Rnum+sport[o-opl], f & 0xff, 0); putcmd(Roct+sport[o-opl], Mkon | o->blk, 0); } void setvol(Opl *o) { int p, w, x; p = port[o - opl]; w = o->v * o->c->v / 127; w = ovol[w * 64 / 127] * 63 / 128; x = 63 + (o->i[5] & Mlvl) * w / 63 - w; putcmd(Rsca+p, o->i[4] & Mscl | x, 0); x = 63 + (o->i[12] & Mlvl) * w / 63 - w; putcmd(Rsca+p+3, o->i[11] & Mscl | x, 0); } void putnote(Chan *c, int midn, int n, int v, vlong t, uchar *i) { Opl *o; o = getch(); o->c = c; o->n = n; o->midn = midn; o->v = v; o->t = t; if(o->i != i) setinst(o, i); setvol(o); setoct(o); } void noteon(Chan *c, int n, int v, vlong t) { int x, m; m = n; if(c - chan == 9){ /* asspull workaround for percussions above gm set */ if(m == 85) m = 37; if(m == 82) m = 44; if(m < 35 || m > 81) return; c->i = inst + 128 + m - 35; } if(c->i->fixed) m = c->i->n; if(v == 0){ noteoff(c, n, 0); return; } x = m + (c->i->fixed ? 0 : c->i->base[0]); while(x < 0) x += 12; while(x > 8*12-1) x -= 12; putnote(c, n, x & 0xff, v, t, c->i->i); if(c->i->dbl){ x = m + (c->i->fixed ? 0 : c->i->base[1]); while(x < 0) x += 12; while(x > 95) x -= 12; putnote(c, n, x & 0xff, v, t, c->i->i2); } } void resetchan(Chan *c) { Opl *o; for(o=opl; o<ople; o++) if(o->c == c && o->n >= 0){ putcmd(Rfed+sport[o-opl], o->i[6] & ~0x30 | c->pan, 0); setvol(o); setoct(o); } } uvlong tc(int n) { return ((uvlong)n * tempo * Rate / div) / 1000000; } void skip(Trk *x, int n) { while(n-- > 0) get8(x); } int getvar(Trk *x) { int v, w; w = get8(x); v = w & 0x7f; while(w & 0x80){ if(v & 0xff000000) sysfatal("invalid variable-length number"); v <<= 7; w = get8(x); v |= w & 0x7f; } return v; } int peekvar(Trk *x) { int v; uchar *p; p = x->p; v = getvar(x); x->p = p; return v; } void samp(uvlong t´) { int dt; static uvlong t; dt = t´ - t; t += dt; while(dt > 0){ putcmd(0, 0, dt > 0xffff ? 0xffff : dt); dt -= 0xffff; } } void ev(Trk *x) { int e, n, m; Chan *c; samp(x->t += tc(getvar(x))); e = get8(x); if((e & 0x80) == 0){ x->p--; e = x->ev; if((e & 0x80) == 0) sysfatal("invalid event"); }else x->ev = e; c = chan + (e & 15); n = get8(x); switch(e >> 4){ case 0x8: noteoff(c, n, get8(x)); break; case 0x9: noteon(c, n, get8(x), x->t); break; case 0xb: m = get8(x); switch(n){ case 0x00: case 0x01: case 0x20: break; case 0x07: c->v = m; resetchan(c); break; case 0x0a: c->pan = m < 32 ? 1<<4 : m > 96 ? 1<<5 : 3<<4; resetchan(c); break; default: fprint(2, "unknown controller %d\n", n); } break; case 0xc: c->i = inst + n; break; case 0xe: n = get8(x) << 7 | n; c->bend = n - 0x4000 / 2; resetchan(c); break; case 0xf: if((e & 0xf) == 0){ while(get8(x) != 0xf7) ; return; } m = get8(x); switch(n){ case 0x2f: x->p = x->e; return; case 0x51: tempo = get16(x) << 8; tempo |= get8(x); break; default: skip(x, m); } break; case 0xa: case 0xd: get8(x); break; default: sysfatal("invalid event %#ux\n", e >> 4); } } void tproc(void *) { vlong t, Δt; uchar u[4]; Trk x; x.e = u + sizeof u; t = nsec(); for(;;){ if(nbrecv(echan, u) > 0){ u[0] = 0; x.p = u; ev(&x); } putcmd(0, 0, 1); t += 10000000 / (Rate / 100); Δt = (t - nsec()) / 1000000; if(Δt > 0) sleep(Δt); } } void readinst(char *file) { int n; uchar u[8]; Inst *i; ib = bopen(file, OREAD); bread(u, sizeof u); if(memcmp(u, "#OPL_II#", sizeof u) != 0) sysfatal("invalid patch file"); for(i=inst; i<inst+nelem(inst); i++){ n = get8(nil); i->fixed = n & 1<<0; i->dbl = opl2 ? 0 : n & 1<<2; get8(nil); i->fine = (get8(nil) - 128) * 64; i->n = get8(nil); bread(i->i, sizeof i->i); get8(nil); n = get8(nil); n |= get8(nil) << 8; i->base[0] = (s16int)n; bread(i->i2, sizeof i->i2); get8(nil); n = get8(nil); n |= get8(nil) << 8; i->base[1] = (s16int)n; } Bterm(ib); } void readmid(char *file) { u32int n; uchar *s; Trk *x; ib = file != nil ? bopen(file, OREAD) : bfdopen(0, OREAD); if(stream) return; if(get32(nil) != 0x4d546864 || get32(nil) != 6) sysfatal("invalid header"); mfmt = get16(nil); ntrk = get16(nil); if(ntrk == 1) mfmt = 0; if(mfmt < 0 || mfmt > 1) sysfatal("unsupported format %d", mfmt); div = get16(nil); tr = emalloc(ntrk * sizeof *tr); for(x=tr; x<tr+ntrk; x++){ if(get32(nil) != 0x4d54726b) sysfatal("invalid track"); n = get32(nil); s = emalloc(n); bread(s, n); x->s = s; x->p = s; x->e = s + n; } Bterm(ib); } void usage(void) { fprint(2, "usage: %s [-2s] [-i inst] [mid]\n", argv0); exits("usage"); } void threadmain(int argc, char **argv) { int n, t, mint; char *i; double f; uchar u[4]; Chan *c; Opl *o; Trk *x, *minx; i = "/mnt/wad/genmidi"; ARGBEGIN{ case '2': opl2 = 1; ople = opl + 9; break; case 'i': i = EARGF(usage()); break; case 's': stream = 1; break; default: usage(); }ARGEND readinst(i); readmid(*argv); ob = bfdopen(1, OWRITE); f = pow(2, 1./12); for(n=0; n<nelem(freq); n++) freq[n] = 440 * pow(f, n - 69); for(c=chan; c<chan+nelem(chan); c++){ c->v = 0x5a; c->bend = 0; c->pan = 3<<4; c->i = inst; } for(o=opl; o<ople; o++) o->n = -1; tempo = 500000; putcmd(Rwse, Mwse, 0); putcmd(Rop3, 1, 0); if(stream){ if(proccreate(tproc, nil, mainstacksize) < 0) sysfatal("proccreate: %r"); if((echan = chancreate(sizeof u, 0)) == nil) sysfatal("chancreate: %r"); for(;;){ if((n = Bread(ib, u, sizeof u)) != sizeof u) break; send(echan, u); } threadexitsall(n < 0 ? "read: %r" : nil); } for(;;){ minx = nil; mint = 0; for(x=tr; x<tr+ntrk; x++){ if(x->p >= x->e) continue; t = x->t + tc(peekvar(x)); if(t < mint || minx == nil){ mint = t; minx = x; } } if(minx == nil) exits(nil); ev(minx); } }