mus: fix note volume and channel selection; simplify

- fix overwriting channel 10 with channel 9
- fix using channel volume instead of last volume when setting note
  (fixes d_doom and others)
- remove useless state

diff --git a/sys/man/1/mus b/sys/man/1/mus
index e787939c9b46e1660e82b1947d43ad4f028631cf..4875d700d44c2b05ac2db67343a78c833312c47f 100644 (file)
--- a/sys/man/1/mus
+++ b/sys/man/1/mus
@@ -20,4 +20,4 @@ or from standard input, and produces a MIDI format file on standard output.
 .B /sys/src/games/mus.c
 .SH HISTORY
 .I Mus
-appeared first for 9front (September, 2015).
+first appeared in 9front (September, 2015).

diff --git a/sys/src/games/mus.c b/sys/src/games/mus.c
index 703207b01b10d30795ebd184aafdfd7c75236d6c..2bf0290fb7967dfd787c7677c5d0c947de95471d 100644 (file)
--- a/sys/src/games/mus.c
+++ b/sys/src/games/mus.c
@@ -2,20 +2,12 @@
 #include <libc.h>
 
 typedef struct Trk Trk;
-typedef struct Ch Ch;
-
-struct Ch{
-       uchar n[128];
-       uchar pitch;
-       uchar ctl[10];
-};
 struct Trk{
        u32int len;
        uchar *dat;
        uchar *p;
        uchar *end;
-       Ch c[16];
-       long delay;
+       uchar v[16];
        int done;
 };
 Trk t;
@@ -38,19 +30,15 @@ r8(void)
        return *t.p++;
 }
 
-u32int
+void
 delay(void)
 {
-       u32int t;
        uchar v;
 
-       t = 0;
        do{
                v = r8();
-               t = t << 7 | v & 0x7f;
                *mp++ = v;
        }while(v & 0x80);
-       return t;
 }
 
 void
@@ -69,71 +57,41 @@ putcmd(uchar *cmd, int n)
 void
 ev(void)
 {
-       uchar e, v;
-       Ch *c;
-       uchar cmd[3], *p;
+       uchar e, v, cmd[3], *p;
 
        e = r8();
-       c = &t.c[e & 15];
        p = cmd;
        switch(e >> 4 & 7){
        case 0:
                v = r8() & 0x7f;
-               c->n[v] = 0;
                *p++ = e | 0x80;
                *p++ = v;
                *p++ = 0x40;
                break;
        case 1:
                v = r8();
-               if(v & 0x80){
-                       c->n[v] = r8() & 0x7f;
-                       c->ctl[3] = c->n[v];
-               }else
-                       c->n[v] = c->ctl[3];
                *p++ = e | 0x80;
                *p++ = v & 0x7f;
-               *p++ = c->n[v];
+               if(v & 0x80)
+                       t.v[e & 15] = r8() & 0x7f;
+               *p++ = t.v[e & 15];
                break;
        case 2:
-               c->pitch = r8();
+               v = r8();
                *p++ = e | 0xc0;
-               PBIT16(p, c->pitch << 7 & 0x7f7f);
+               PBIT16(p, v << 7 & 0x7f7f);
                p += 2;
                break;
        case 3:
                v = r8();
                *p++ = 0xb | e & 15;
                switch(v){
-               case 10:
-                       for(v=0; v<128; v++)
-                               c->n[v] = 0;
-                       *p++ = 0x78;
-                       break;
-               case 11:
-                       for(v=0; v<128; v++)
-                               c->n[v] = 0;
-                       *p++ = 0x7b;
-                       break;
-               case 12:
-                       *p++ = 0x7e;
-                       break;
-               case 13:
-                       *p++ = 0x7f;
-                       break;
-               case 14:
-                       memset(c->n, 0, sizeof c->n);
-                       memset(c->ctl, 0, sizeof c->ctl);
-                       c->ctl[3] = 0x7f;
-                       c->ctl[4] = 64;
-                       if((e & 15) == 15)
-                               c->pitch = 60;
-                       else
-                               c->pitch = 128;
-                       *p++ = 0x79;
-                       break;
-               default:
-                       sysfatal("unknown system event %ux\n", v);
+               case 10: *p++ = 0x78; break;
+               case 11: *p++ = 0x7b; break;
+               case 12: *p++ = 0x7e; break;
+               case 13: *p++ = 0x7f; break;
+               case 14: *p++ = 0x79; break;
+               default: sysfatal("unknown system event %ux\n", v);
                }
                *p++ = 0;
                break;
@@ -141,7 +99,6 @@ ev(void)
                v = r8();
                if(v > 9)
                        sysfatal("unknown controller %ux\n", v);
-               c->ctl[v] = r8() & 0x7f;
                *p++ = 0xb0 | e & 15;
                switch(v){
                case 1: *p++ = 0x00; break;
@@ -154,7 +111,7 @@ ev(void)
                case 8: *p++ = 0x40; break;
                case 9: *p++ = 0x43; break;
                }
-               *p++ = c->ctl[v];
+               *p++ = r8() & 0x7f;
                if(v == 0)
                        cmd[0] += 0x10;
                break;
@@ -168,13 +125,12 @@ ev(void)
                sysfatal("unknown event %ux\n", e >> 4 & 7);
        }
        if((e & 15) == 9)
-               cmd[0] += 1;
+               cmd[0] |= 6;
        if((e & 15) == 15)
                cmd[0] &= ~6;
        putcmd(cmd, p-cmd);
-       t.delay = 0;
        if(e & 0x80)
-               t.delay = delay();
+               delay();
        else
                *mp++ = 0;
 }
@@ -182,16 +138,7 @@ ev(void)
 void
 reset(void)
 {
-       Ch *c;
-
-       c = t.c;
-       while(c < t.c + nelem(t.c)){
-               c->pitch = 128;
-               c->ctl[3] = 0x7f;
-               c->ctl[4] = 64;
-               c++;
-       }
-       t.c[15].pitch = 60;
+       memset(t.v, 0x7f, sizeof t.v);
        mcmd = mallocz(t.len * 2, 1);
        if(mcmd == nil)
                sysfatal("mallocz: %r");
@@ -221,6 +168,11 @@ barf(void)
                0x00, 0xb8, 0x07, 0x7f,
                0x00, 0xb9, 0x07, 0x7f,
                0x00, 0xba, 0x07, 0x7f,
+               0x00, 0xbb, 0x07, 0x7f,
+               0x00, 0xbc, 0x07, 0x7f,
+               0x00, 0xbd, 0x07, 0x7f,
+               0x00, 0xbe, 0x07, 0x7f,
+               0x00, 0xbf, 0x07, 0x7f,
                0x00, 0xff, 0x51, 0x03, 0x1b, 0x8a, 0x06,
                0x00
        };