vdp rendering fixes

diff --git a/pico/draw.c b/pico/draw.c
index dff5e07..68af73e 100644 (file)
--- a/pico/draw.c
+++ b/pico/draw.c
@@ -486,7 +486,10 @@ 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
-    plane_sh |= PicoMem.vsram[0x26+(~plane_sh&1)] << 16;\r
+    // vscroll value for leftmost cells in case of hscroll not on 16px boundary\r
+    // XXX it's unclear what exactly the hw is doing. Continue reading where it\r
+    // stopped last seems to work best (H40: 0x50 (wrap->0x00), H32 0x40).\r
+    plane_sh |= PicoMem.vsram[(pvid->reg[12]&1?0x00:0x20) + (plane_sh&1)] << 16;\r
     DrawStripVSRam(&ts, plane_sh, cellskip);\r
   } else {\r
     vscroll = PicoMem.vsram[plane_sh & 1]; // Get vertical scroll value\r
@@ -1173,7 +1176,10 @@ static void DrawLayerForced(int plane_sh, 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
-    plane_sh |= PicoMem.vsram[0x26+(~plane_sh&1)] << 16;\r
+    // vscroll value for leftmost cells in case of hscroll not on 16px boundary\r
+    // XXX it's unclear what exactly the hw is doing. Continue reading where it\r
+    // stopped last seems to work best (H40: 0x50 (wrap->0x00), H32 0x40).\r
+    plane_sh |= PicoMem.vsram[(pvid->reg[12]&1?0x00:0x20) + (plane_sh&1)] << 16;\r
     DrawStripVSRamForced(&ts, plane_sh, cellskip);\r
   } else {\r
     vscroll = PicoMem.vsram[plane_sh & 1]; // Get vertical scroll value\r
@@ -1191,7 +1197,7 @@ static void DrawSpritesForced(unsigned char *sprited)
 {\r
   unsigned (*fTileFunc)(unsigned char *pd, unsigned m, unsigned int pack, int pal);\r
   unsigned char *pd = Pico.est.HighCol;\r
-  unsigned char mb[1+320+1];\r
+  unsigned char mb[1+320/8+1];\r
   unsigned char *p, *mp;\r
   unsigned m;\r
   int entry, cnt;\r

diff --git a/pico/draw_arm.S b/pico/draw_arm.S
index 1a0f351..2ae6dba 100644 (file)
--- a/pico/draw_arm.S
+++ b/pico/draw_arm.S
@@ -523,6 +523,9 @@ DrawLayer:
 @ @@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@\r
 \r
 .DrawStrip_vsscroll:\r
+    tst     r8, #1                @ if h40: lflags |= 0x10000\r
+    orrne   r0, r0, #0x10000\r
+\r
     rsb     r8, r3, #0\r
     mov     r8, r8, lsr #3        @ r8=tilex=(-ts->hscroll)>>3\r
     bic     r8, r8, #0x3fc00000\r
@@ -545,11 +548,13 @@ DrawLayer:
     eor     r3, r3, r7\r
     sub     r10,r10, #1<<24       @ cell--  // start from negative for hscroll\r
     tst     r3, #0x08\r
-    add_c24 r1, lr, (OFS_PMEM_vsram-OFS_PMEM_vram)\r
-    ldr     r3, [r1, #0x4c]       @ r3=vsram[0x26..0x27]\r
     subne   r10,r10, #1<<16       @ cells--\r
     subne   r10,r10, #1<<24       @ cell--  // even more negative\r
-    ror     r3, r3, #16\r
+\r
+    add_c24 r1, lr, (OFS_PMEM_vsram-OFS_PMEM_vram)\r
+    tst     r0, #0x10000          @ h40?\r
+    ldrne   r3, [r1, #0x00]       @ r3=vsram[0x00..0x01]\r
+    ldreq   r3, [r1, #0x40]       @ r3=vsram[0x20..0x21]\r
     str     r3, [r1, #0x7c]       @ vsram[0x3e..0x3f]=r3\r
 0:\r
     tst     r9, #1<<31\r