From: kub <derkub@gmail.com>
Date: Sun, 26 Mar 2023 10:33:29 +0000 (+0000)
Subject: md vdp, fix sprite parsing (done on previous line)
X-Git-Tag: v2.00~246
X-Git-Url: https://notaz.gp2x.de/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=ac89144969e16ddd99b9ff3cd32df3aca52b6ded;p=picodrive.git

md vdp, fix sprite parsing (done on previous line)
---

diff --git a/pico/draw.c b/pico/draw.c
index c1e8c4d3..011a1a39 100644
--- a/pico/draw.c
+++ b/pico/draw.c
@@ -63,7 +63,7 @@ static u32 HighCacheA[41*2+1]; // caches for high layers
 static u32 HighCacheB[41*2+1];
 static s32 HighPreSpr[80*2+1]; // slightly preprocessed sprites
 
-u32 VdpSATCache[128];  // VDP sprite cache (1st 32 sprite attr bits)
+u32 VdpSATCache[2*128];  // VDP sprite cache (1st 32 sprite attr bits)
 
 // NB don't change any defines without checking their usage in ASM
 
@@ -1401,7 +1401,7 @@ static void DrawSpritesForced(unsigned char *sprited)
 // Index + 0  :    hhhhvvvv ----hhvv yyyyyyyy yyyyyyyy // v, h: vert./horiz. size
 // Index + 4  :    xxxxxxxx xxxxxxxx pccvhnnn nnnnnnnn // x: x coord + 8
 
-static NOINLINE void PrepareSprites(int max_lines)
+static NOINLINE void ParseSprites(int max_lines)
 {
   const struct PicoVideo *pvid=&Pico.video;
   const struct PicoEState *est=&Pico.est;
@@ -1411,6 +1411,12 @@ static NOINLINE void PrepareSprites(int max_lines)
   int max_sprites = 80, max_width = 328;
   int max_line_sprites = 20; // 20 sprites, 40 tiles
 
+  // SAT scanning is one line ahead, but don't overshoot. Technically, SAT
+  // parsing for line 0 is on the last line of the previous frame.
+  int first_line = Pico.est.DrawScanline + !!Pico.est.DrawScanline;
+  if (max_lines > rendlines-1)
+    max_lines = rendlines-1;
+
   if (!(Pico.video.reg[12]&1))
     max_sprites = 64, max_line_sprites = 16, max_width = 264;
   if (*est->PicoOpt & POPT_DIS_SPRITE_LIM)
@@ -1422,7 +1428,7 @@ static NOINLINE void PrepareSprites(int max_lines)
   if (pvid->reg[12]&1) table&=0x7e; // Lowest bit 0 in 40-cell mode
   table<<=8; // Get sprite table address/2
 
-  for (u = est->DrawScanline; u < max_lines; u++)
+  for (u = first_line; u <= max_lines; u++)
     *((int *)&HighLnSpr[u][0]) = 0;
 
   for (u = 0; u < max_sprites && link < max_sprites; u++)
@@ -1434,7 +1440,7 @@ static NOINLINE void PrepareSprites(int max_lines)
 
     // parse sprite info. the 1st half comes from the VDPs internal cache,
     // the 2nd half is read from VRAM
-    code = CPU_LE2(VdpSATCache[link]); // normally same as sprite[0]
+    code = CPU_LE2(VdpSATCache[2*link]); // normally same as sprite[0]
     sy = (code&0x1ff)-0x80;
     hv = (code>>24)&0xf;
     height = (hv&3)+1;
@@ -1444,7 +1450,7 @@ static NOINLINE void PrepareSprites(int max_lines)
     sx = (code2>>16)&0x1ff;
     sx -= 0x78; // Get X coordinate + 8
 
-    if (sy < max_lines && sy + (height<<3) >= est->DrawScanline) // sprite onscreen (y)?
+    if (sy <= max_lines && sy + (height<<3) >= first_line) // sprite onscreen (y)?
     {
       int entry, y, w, sx_min, onscr_x, maybe_op = 0;
 
@@ -1454,8 +1460,8 @@ static NOINLINE void PrepareSprites(int max_lines)
         maybe_op = SPRL_MAY_HAVE_OP;
 
       entry = ((pd - HighPreSpr) / 2) | ((code2>>8)&0x80);
-      y = (sy >= est->DrawScanline) ? sy : est->DrawScanline;
-      for (; y < sy + (height<<3) && y < max_lines; y++)
+      y = (sy >= first_line) ? sy : first_line;
+      for (; y < sy + (height<<3) && y <= max_lines; y++)
       {
         unsigned char *p = &HighLnSpr[y][0];
         int cnt = p[0];
@@ -1501,7 +1507,7 @@ static NOINLINE void PrepareSprites(int max_lines)
   *pd = 0;
 
 #if 0
-  for (u = 0; u < max_lines; u++)
+  for (u = first_line; u <= max_lines; u++)
   {
     int y;
     printf("c%03i: f %x c %2i/%2i w %2i: ", u, HighLnSpr[u][1],
@@ -1982,9 +1988,9 @@ void PicoDrawSync(int to, int blank_last_line)
     if (to > 223)
       to = 223;
   }
-  if (est->DrawScanline <= to - blank_last_line && (est->rendstatus &
+  if (est->DrawScanline <= to && (est->rendstatus &
                 (PDRAW_SPRITES_MOVED|PDRAW_DIRTY_SPRITES|PDRAW_PARSE_SPRITES)))
-    PrepareSprites(to - blank_last_line + 1);
+    ParseSprites(to + 1);
 
   for (line = est->DrawScanline; line < to; line++)
     PicoLine(line, offs, sh, bgc);
diff --git a/pico/pico_int.h b/pico/pico_int.h
index 1bb7b258..e330413d 100644
--- a/pico/pico_int.h
+++ b/pico/pico_int.h
@@ -705,7 +705,7 @@ extern unsigned char *HighColBase;
 extern int HighColIncrement;
 extern void *DrawLineDestBase;
 extern int DrawLineDestIncrement;
-extern u32 VdpSATCache[128];
+extern u32 VdpSATCache[2*128];
 
 // draw2.c
 void PicoDraw2SetOutBuf(void *dest, int incr);
@@ -890,9 +890,7 @@ static __inline void UpdateSAT(u32 a, u32 d)
   unsigned num = (a^SATaddr) >> 3;
 
   Pico.est.rendstatus |= PDRAW_DIRTY_SPRITES;
-  if (!(a & 4) && num < 128) {
-    ((u16 *)&VdpSATCache[num])[(a&3) >> 1] = d;
-  }
+  ((u16 *)&VdpSATCache[2*num])[(a&7) >> 1] = d;
 }
 static __inline void VideoWriteVRAM(u32 a, u16 d)
 {
diff --git a/pico/videoport.c b/pico/videoport.c
index 7f567f17..ce356f66 100644
--- a/pico/videoport.c
+++ b/pico/videoport.c
@@ -1104,8 +1104,8 @@ void PicoVideoCacheSAT(int load)
     SATaddr &= ~0x200, SATmask &= ~0x200; // H40, zero lowest SAT bit
 
   // rebuild SAT cache XXX wrong since cache and memory can differ
-  for (l = 0; load && l < 80; l++) {
-    u16 addr = SATaddr + l*8;
+  for (l = 0; load && l < 2*80; l ++) {
+    u16 addr = SATaddr + l*4;
     ((u16 *)VdpSATCache)[l*2    ] = PicoMem.vram[(addr>>1)    ];
     ((u16 *)VdpSATCache)[l*2 + 1] = PicoMem.vram[(addr>>1) + 1];
   }