vdp rendering improvements

diff --git a/pico/draw.c b/pico/draw.c
index 833d87c..eeeb553 100644 (file)
--- a/pico/draw.c
+++ b/pico/draw.c
@@ -324,7 +324,7 @@ static void DrawStripVSRam(struct TileStrip *ts, int plane_sh, int cellskip)
     //if((cell&1)==0)\r
     {\r
       int line,vscroll;\r
-      vscroll=PicoMem.vsram[(plane_sh&1)+(cell&~1)];\r
+      vscroll=PicoMem.vsram[(plane_sh&1)+(cell&0x3e)];\r
 \r
       // Find the line in the name table\r
       line=(vscroll+scan)&ts->line&0xffff; // ts->line is really ymask ..\r
@@ -479,6 +479,7 @@ static void DrawLayer(int plane_sh, int *hcache, int cellskip, int maxcells,
     // shit, we have 2-cell column based vscroll\r
     // luckily this doesn't happen too often\r
     ts.line=ymask|(shift[width]<<24); // save some stuff instead of line\r
+    PicoMem.vsram[(plane_sh & 1)+0x3e] = PicoMem.vsram[0x27]; // XXX really?\r
     DrawStripVSRam(&ts, plane_sh, cellskip);\r
   } else {\r
     vscroll = PicoMem.vsram[plane_sh & 1]; // Get vertical scroll value\r
@@ -1022,7 +1023,7 @@ static void DrawSpritesHiAS(unsigned char *sprited, int sh)
 \r
     if (entry+1 == cnt) width = p[entry+1]; // last sprite width limited?\r
     mp = mb+(sx>>3);\r
-    for (m = *mp << 8; width; width--, sx+=8, *mp++ = m, tile+=delta)\r
+    for (m = *mp; width; width--, sx+=8, *mp++ = m, m >>= 8, tile+=delta)\r
     {\r
       unsigned int pack;\r
 \r
@@ -1031,11 +1032,11 @@ static void DrawSpritesHiAS(unsigned char *sprited, int sh)
 \r
       pack = *(unsigned int *)(PicoMem.vram + (tile & 0x7fff));\r
 \r
-      m = (m >> 8) | mp[1] << 8; // next mask byte\r
+      m |= mp[1] << 8; // next mask byte\r
       // shift mask bits to bits 8-15 for easier load/store handling\r
       m = fTileFunc(pd + sx, m << (8-(sx&0x7)), pack, pal) >> (8-(sx&0x7));\r
     } \r
-    *mp = m >> 8; // write last mask byte\r
+    *mp = m; // write last mask byte\r
   }\r
 }\r
 \r
@@ -1428,10 +1429,6 @@ static int DrawDisplay(int sh)
   int win=0, edge=0, hvwind=0, lflags;\r
   int maxw, maxcells;\r
 \r
-  if (!(est->DrawScanline & 15) ||\r
-      (est->rendstatus & (PDRAW_SPRITES_MOVED|PDRAW_DIRTY_SPRITES)))\r
-    PrepareSprites((est->DrawScanline+16) & ~15);\r
-\r
   est->rendstatus &= ~(PDRAW_SPRITES_MOVED|PDRAW_DIRTY_SPRITES);\r
   est->rendstatus &= ~(PDRAW_SHHI_DONE|PDRAW_PLANE_HI_PRIO);\r
 \r
@@ -1646,6 +1643,8 @@ void PicoDrawSync(int to, int blank_last_line)
     if (to > 223)\r
       to = 223;\r
   }\r
+  if (Pico.est.DrawScanline <= to - blank_last_line)\r
+    PrepareSprites(to - blank_last_line + 1);\r
 \r
   for (line = Pico.est.DrawScanline; line < to; line++)\r
     PicoLine(line, offs, sh, bgc);\r