merge

[plan9front.git] / sys / src / games / snes / ppu.c

diff --git a/sys/src/games/snes/ppu.c b/sys/src/games/snes/ppu.c
index 808165d8deba925b822ebba02803988a83779e72..5edc52f5e069277e9bb703d65839c1f0bece3a24 100644 (file)
--- a/sys/src/games/snes/ppu.c
+++ b/sys/src/games/snes/ppu.c
@@ -9,7 +9,17 @@ static u8int mode, bright, pixelpri[2];
 static u32int pixelcol[2];
 u16int vtime = 0x1ff, htime = 0x1ff, subcolor, mosatop;
 uchar pic[256*239*2*9];
-u16int m7[6], hofs[4], vofs[4];
+u16int hofs[5], vofs[5];
+s16int m7[6];
+
+enum {
+       M7A,
+       M7B,
+       M7C,
+       M7D,
+       M7X,
+       M7Y
+};
 
 enum { OBJ = 4, COL = 5, OBJNC = 8 };
 
@@ -270,8 +280,8 @@ redo:
        p->t = tile(n, p->tx, p->ty);
        chr(n, nb, p->sz, p->t, p->tnx, p->tny, p->c);
        p->pal = palette(n, p->t >> 10 & 7);
-       if(p->tnx != 0)
-               shift(p->c, nb, p->tnx, p->t & 0x4000);
+       if((p->tnx & 7) != 0)
+               shift(p->c, nb, p->tnx & 7, p->t & 0x4000);
        if(p->msz != 1 && p->mx != 0 && sx % p->msz == 0){
                p->mv = bgpixel(p->c, nb, p->t & 0x4000);
                if(p->tnx + p->mx >= 8){
@@ -311,6 +321,117 @@ bg(int n)
                chr(n, p->nb, p->sz, p->t, p->tnx, p->tny, p->c);
 }
 
+struct bg7ctxt {
+       int x, y, x0, y0;
+       u8int msz, mx, mv;
+} b7[2];
+
+void
+calc7(void)
+{
+       s16int t;
+
+       if((reg[0x2105] & 7) != 7)
+               return;
+       t = hofs[4] - m7[M7X];
+       if((t & 0x2000) != 0)
+               t |= ~0x3ff;
+       else
+               t &= 0x3ff;
+       b7->x0 = (t * m7[M7A]) & ~63;
+       b7->y0 = (t * m7[M7C]) & ~63;
+       t = vofs[4] - m7[M7Y];
+       if((t & 0x2000) != 0)
+               t |= ~0x3ff;
+       else
+               t &= 0x3ff;
+       b7->x0 += (t * m7[M7B]) & ~63;
+       b7->y0 += (t * m7[M7D]) & ~63;
+       b7->x0 += m7[M7X] << 8;
+       b7->y0 += m7[M7Y] << 8;
+}
+
+static void
+bg7init(int n)
+{
+       u8int m, y;
+       struct bg7ctxt *p;
+       
+       p = b7 + n;
+       m = reg[M7SEL];
+       y = ppuy;
+       p->msz = 1;
+       if((reg[MOSAIC] & 1) != 0){
+               p->msz = (reg[MOSAIC] >> 4) + 1;
+               if(p->msz != 1)
+                       y -= y % p->msz;
+       }
+       if(n == 1)
+               if((reg[MOSAIC] & 2) != 0)
+                       p->msz = (reg[MOSAIC] >> 4) + 1;
+               else
+                       p->msz = 1;
+       if((m & 2) != 0)
+               y = 255 - y;
+       p->x = b7->x0 + ((m7[M7B] * y) & ~63);
+       p->y = b7->y0 + ((m7[M7D] * y) & ~63);
+       if((m & 1) != 0){
+               p->x += 255 * m7[M7A];
+               p->y += 255 * m7[M7C];
+       }
+}
+
+static void
+bg7(int n)
+{
+       u16int x, y;
+       u8int m, v, t;
+       struct bg7ctxt *p;
+
+       p = b7 + n;
+       m = reg[M7SEL];
+       x = p->x >> 8;
+       y = p->y >> 8;
+       if((m & 0x80) == 0){
+               x &= 1023;
+               y &= 1023;
+       }else if(x > 1023 || y > 1023){
+               if((m & 0x40) != 0){
+                       t = 0;
+                       goto lookup;
+               }
+               v = 0;
+               goto end;
+       }
+       t = vram[x >> 2 & 0xfe | y << 5 & 0x7f00];
+lookup:
+       v = vram[t << 7 | y << 4 & 0x70 | x << 1 & 0x0e | 1];
+end:
+       if(p->msz != 1){
+               if(p->mx == 0)
+                       p->mv = v;
+               else
+                       v = p->mv;
+               if(++p->mx == p->msz)
+                       p->mx = 0;
+       }
+       if(n == 1){
+               if((v & 0x7f) != 0)
+                       if((v & 0x80) != 0)
+                               pixel(1, v & 0x7f, 0x71);
+                       else
+                               pixel(1, v, 0x11);
+       }else if(v != 0)
+               pixel(0, v, 0x40);
+       if((m & 1) != 0){
+               p->x -= m7[M7A];
+               p->y -= m7[M7C];
+       }else{
+               p->x += m7[M7A];
+               p->y += m7[M7C];
+       }
+}
+
 static void
 bgsinit(void)
 {
@@ -336,6 +457,11 @@ bgsinit(void)
                bginit(0, 8, 0x40, 0xa0);
                bginit(1, 4, 0x11, 0x71);
                break;
+       case 7:
+               bg7init(0);
+               if((reg[SETINI] & EXTBG) != 0)
+                       bg7init(1);
+               break;
        default:
                bgctxts[0].sz = bgctxts[1].sz = 0;
                if(bitch[mode]++ == 0)
@@ -363,6 +489,11 @@ bgs(void)
                bg(0);
                bg(1);
                break;
+       case 7:
+               bg7(0);
+               if((reg[SETINI] & EXTBG) != 0)
+                       bg7(1);
+               break;
        }
 }