From e721f801366a35bc7b71c96b21609c890ece6c30 Mon Sep 17 00:00:00 2001
From: kub <derkub@gmail.com>
Date: Mon, 21 Sep 2020 21:02:51 +0200
Subject: [PATCH] vdp, fix for gfx save/load menu bg

---
 pico/pico.h           |  2 +-
 pico/pico_int.h       |  3 ++-
 pico/state.c          |  5 +++++
 pico/videoport.c      | 33 ++++++++++++++++++++-------------
 platform/common/emu.c |  1 +
 5 files changed, 29 insertions(+), 15 deletions(-)

diff --git a/pico/pico.h b/pico/pico.h
index 4cc29433..3c800f6a 100644
--- a/pico/pico.h
+++ b/pico/pico.h
@@ -197,7 +197,7 @@ void PicoDrawSetCallbacks(int (*begin)(unsigned int num), int (*end)(unsigned in
 void vidConvCpyRGB565(void *to, void *from, int pixels);
 #endif
 void PicoDoHighPal555(int sh, int line, struct PicoEState *est);
-// internals
+// internals, NB must keep in sync with ASM draw functions
 #define PDRAW_SPRITES_MOVED (1<<0) // SAT address modified
 #define PDRAW_WND_DIFF_PRIO (1<<1) // not all window tiles use same priority
 #define PDRAW_PARSE_SPRITES (1<<2) // SAT needs parsing
diff --git a/pico/pico_int.h b/pico/pico_int.h
index 1a1205f8..86cfb778 100644
--- a/pico/pico_int.h
+++ b/pico/pico_int.h
@@ -846,7 +846,7 @@ void ym2612_unpack_state(void);
 extern unsigned SATaddr, SATmask;
 static __inline void UpdateSAT(u32 a, u32 d)
 {
-  unsigned num = (a-SATaddr) >> 3;
+  unsigned num = (a^SATaddr) >> 3;
 
   Pico.est.rendstatus |= PDRAW_DIRTY_SPRITES;
   if (!(a & 4) && num < 128) {
@@ -876,6 +876,7 @@ void PicoVideoFIFOMode(int active, int h40);
 int PicoVideoFIFOWrite(int count, int byte_p, unsigned sr_mask, unsigned sr_flags);
 void PicoVideoSave(void);
 void PicoVideoLoad(void);
+void PicoVideoCacheSAT(void);
 
 // misc.c
 PICO_INTERNAL_ASM void memcpy16bswap(unsigned short *dest, void *src, int count);
diff --git a/pico/state.c b/pico/state.c
index da6b6fd8..17164251 100644
--- a/pico/state.c
+++ b/pico/state.c
@@ -710,6 +710,8 @@ int PicoStateLoadGfx(const char *fname)
     areaRead(&Pico.video, 1, sizeof(Pico.video), afile);
   }
   areaClose(afile);
+
+  PicoVideoCacheSAT();
   return 0;
 }
 
@@ -719,6 +721,7 @@ struct PicoTmp
   unsigned short vram[0x8000];
   unsigned short cram[0x40];
   unsigned short vsram[0x40];
+  unsigned int satcache[0x80];
 
   //struct PicoMisc m;
   struct PicoVideo video;
@@ -741,6 +744,7 @@ void *PicoTmpStateSave(void)
   memcpy(t->vram, PicoMem.vram, sizeof(PicoMem.vram));
   memcpy(t->cram, PicoMem.cram, sizeof(PicoMem.cram));
   memcpy(t->vsram, PicoMem.vsram, sizeof(PicoMem.vsram));
+  memcpy(t->satcache, VdpSATCache, sizeof(VdpSATCache));
   memcpy(&t->video, &Pico.video, sizeof(Pico.video));
 
 #ifndef NO_32X
@@ -763,6 +767,7 @@ void PicoTmpStateRestore(void *data)
   memcpy(PicoMem.vram, t->vram, sizeof(PicoMem.vram));
   memcpy(PicoMem.cram, t->cram, sizeof(PicoMem.cram));
   memcpy(PicoMem.vsram, t->vsram, sizeof(PicoMem.vsram));
+  memcpy(VdpSATCache, t->satcache, sizeof(VdpSATCache));
   memcpy(&Pico.video, &t->video, sizeof(Pico.video));
   Pico.m.dirtyPal = 1;
 
diff --git a/pico/videoport.c b/pico/videoport.c
index cbcc60d3..fec862f7 100644
--- a/pico/videoport.c
+++ b/pico/videoport.c
@@ -999,6 +999,25 @@ unsigned char PicoVideoRead8HV_L(void)
   return d;
 }
 
+void PicoVideoCacheSAT(void)
+{
+  struct PicoVideo *pv = &Pico.video;
+  int l;
+
+  SATaddr = ((pv->reg[5]&0x7f) << 9) | ((pv->reg[6]&0x20) << 11);
+  SATmask = ~0x1ff;
+  if (pv->reg[12]&1)
+    SATaddr &= ~0x200, SATmask &= ~0x200; // H40, zero lowest SAT bit
+
+  // rebuild SAT cache XXX wrong since cache and memory can differ
+  for (l = 0; l < 80; l++) {
+    ((u16 *)VdpSATCache)[l*2    ] = PicoMem.vram[(SATaddr>>1) + l*4    ];
+    ((u16 *)VdpSATCache)[l*2 + 1] = PicoMem.vram[(SATaddr>>1) + l*4 + 1];
+  }
+
+  Pico.est.rendstatus |= PDRAW_SPRITES_MOVED;
+}
+
 void PicoVideoSave(void)
 {
   struct VdpFIFO *vf = &VdpFIFO;
@@ -1014,7 +1033,6 @@ void PicoVideoLoad(void)
 {
   struct VdpFIFO *vf = &VdpFIFO;
   struct PicoVideo *pv = &Pico.video;
-  int l;
 
   // convert former dma_xfers (why was this in PicoMisc anyway?)
   if (Pico.m.dma_xfers) {
@@ -1023,17 +1041,6 @@ void PicoVideoLoad(void)
     vf->fifo_total = Pico.m.dma_xfers;
     Pico.m.dma_xfers = 0;
   }
-
-  SATaddr = ((pv->reg[5]&0x7f) << 9) | ((pv->reg[6]&0x20) << 11);
-  SATmask = ~0x1ff;
-  if (pv->reg[12]&1)
-    SATaddr &= ~0x200, SATmask &= ~0x200; // H40, zero lowest SAT bit
-
-  // rebuild SAT cache XXX wrong since cache and memory can differ
-  for (l = 0; l < 80; l++) {
-    *((u16 *)VdpSATCache + 2*l  ) = PicoMem.vram[(SATaddr>>1) + l*4    ];
-    *((u16 *)VdpSATCache + 2*l+1) = PicoMem.vram[(SATaddr>>1) + l*4 + 1];
-  }
+  PicoVideoCacheSAT();
 }
-
 // vim:shiftwidth=2:ts=2:expandtab
diff --git a/platform/common/emu.c b/platform/common/emu.c
index 15aa5392..04e26bf4 100644
--- a/platform/common/emu.c
+++ b/platform/common/emu.c
@@ -1219,6 +1219,7 @@ void emu_cmn_forced_frame(int no_scale, int do_emu)
 
 	PicoDrawSetOutFormat(PDF_RGB555, 1);
 	Pico.m.dirtyPal = 1;
+	Pico.est.rendstatus |= PDRAW_DIRTY_SPRITES;
 	if (do_emu)
 		PicoFrame();
 	else
-- 
2.39.5