ref: 3a54967108ab173389448ba2145502cf62602111
parent: a6f3ba79c2b50bb6f946a7c5904859971dee6908
author: aiju <devnull@localhost>
date: Thu Mar 20 11:21:53 EDT 2014
games/snes: added offset-per-tile
--- a/sys/src/games/snes/ppu.c
+++ b/sys/src/games/snes/ppu.c
@@ -248,6 +248,7 @@
u32int c[2];
int pal;
u8int msz, mv, mx;
+ u16int otx, oty, otny;
} bgctxts[4];
static void
@@ -321,6 +322,101 @@
chr(n, p->nb, p->sz, p->t, p->tnx, p->tny, p->c);
}
+static void
+optinit(void)
+{+ struct bgctxt *p;
+
+ p = bgctxts + 2;
+ p->szsh = (reg[BGMODE] & (1<<6)) != 0 ? 4 : 3;
+ p->sz = 1<<p->szsh;
+ p->tnx = hofs[2] & (p->sz - 1);
+ p->tx = hofs[2] >> p->szsh;
+ bgctxts[0].otx = bgctxts[1].otx = 0xffff;
+ bgctxts[0].oty = bgctxts[0].ty;
+ bgctxts[0].otny = bgctxts[0].tny;
+ bgctxts[1].oty = bgctxts[1].ty;
+ bgctxts[1].otny = bgctxts[1].tny;
+}
+
+static void
+opt(void)
+{+ struct bgctxt *p;
+ u16int hval, vval;
+ int sx, sy;
+
+ p = bgctxts + 2;
+ if(++p->tnx == p->sz){+ if(mode == 4){+ hval = tile(2, p->tx, vofs[2] >> p->szsh);
+ if((hval & 0x8000) != 0){+ vval = hval;
+ hval = 0;
+ }else
+ vval = 0;
+ }else{+ hval = tile(2, p->tx, vofs[2] >> p->szsh);
+ vval = tile(2, p->tx, (vofs[2]+8) >> p->szsh);
+ }
+ sx = (rx & ~7) + (hval & 0x1ff8);
+ sy = ppuy + (vval & 0x1fff);
+ if((vval & 0x2000) != 0){+ bgctxts[0].oty = sy >> bgctxts[0].szsh;
+ bgctxts[0].otny = sy & (bgctxts[0].sz - 1);
+ }else{+ bgctxts[0].oty = bgctxts[0].ty;
+ bgctxts[0].otny = bgctxts[0].tny;
+ }
+ if((vval & 0x4000) != 0){+ bgctxts[1].oty = sy >> bgctxts[1].szsh;
+ bgctxts[1].otny = sy & (bgctxts[1].sz - 1);
+ }else{+ bgctxts[1].oty = bgctxts[1].ty;
+ bgctxts[1].otny = bgctxts[1].tny;
+ }
+ if((hval & 0x2000) != 0)
+ bgctxts[0].otx = sx >> bgctxts[0].szsh;
+ else
+ bgctxts[0].otx = 0xffff;
+ if((hval & 0x4000) != 0)
+ bgctxts[1].otx = sx >> bgctxts[1].szsh;
+ else
+ bgctxts[1].otx = 0xffff;
+ p->tnx = 0;
+ p->tx++;
+ }
+}
+
+static void
+bgopt(int n)
+{+ struct bgctxt *p;
+ u8int v;
+
+ p = bgctxts + n;
+ v = bgpixel(p->c, p->nb, p->t & 0x4000);
+ if(p->msz != 1)
+ if(p->mx++ == 0)
+ p->mv = v;
+ else{+ if(p->mx == p->msz)
+ p->mx = 0;
+ v = p->mv;
+ }
+ if(v != 0)
+ pixel(n, p->pal + v, p->pri[(p->t & 0x2000) != 0]);
+ if(++p->tnx == p->sz){+ p->tx++;
+ p->tnx = 0;
+ }
+ if((p->tnx & 7) == 0){+ p->t = tile(n, p->otx == 0xffff ? p->tx : p->otx, p->oty);
+ p->pal = palette(n, p->t >> 10 & 7);
+ chr(n, p->nb, p->sz, p->t, p->tnx, p->otny, p->c);
+ }
+}
+
struct bg7ctxt {int x, y, x0, y0;
u8int msz, mx, mv;
@@ -452,11 +548,17 @@
case 2:
bginit(0, 4, 0x40, 0xa0);
bginit(1, 4, 0x11, 0x71);
+ optinit();
break;
case 3:
bginit(0, 8, 0x40, 0xa0);
bginit(1, 4, 0x11, 0x71);
break;
+ case 4:
+ bginit(0, 8, 0x40, 0xa0);
+ bginit(1, 2, 0x11, 0x71);
+ optinit();
+ break;
case 7:
bg7init(0);
if((reg[SETINI] & EXTBG) != 0)
@@ -485,6 +587,11 @@
bg(2);
break;
case 2:
+ case 4:
+ opt();
+ bgopt(0);
+ bgopt(1);
+ break;
case 3:
bg(0);
bg(1);