From c180662e07d428ca4c2c9a39fdb152d4fcacc6dd Mon Sep 17 00:00:00 2001
From: kub <derkub@gmail.com>
Date: Sun, 3 Dec 2023 17:46:59 +0100
Subject: [PATCH] sms, improve changing of video mode

---
 pico/draw.c  |  2 +-
 pico/mode4.c | 27 +++++++++++++++------------
 2 files changed, 16 insertions(+), 13 deletions(-)

diff --git a/pico/draw.c b/pico/draw.c
index f6a710c5..66b4fca5 100644
--- a/pico/draw.c
+++ b/pico/draw.c
@@ -1943,7 +1943,7 @@ PICO_INTERNAL void PicoFrameStart(void)
 
   if (est->rendstatus != rendstatus_old || lines != rendlines) {
     rendlines = lines;
-    // mode_change() might reset rendstatus_old by calling SetColorFormat
+    // mode_change() might reset rendstatus_old by calling SetOutFormat
     int rendstatus = est->rendstatus;
     emu_video_mode_change(loffs, lines, coffs, columns);
     rendstatus_old = rendstatus;
diff --git a/pico/mode4.c b/pico/mode4.c
index b56cf442..78108ec0 100644
--- a/pico/mode4.c
+++ b/pico/mode4.c
@@ -728,11 +728,12 @@ static void FinalizeLine8bitSMS(int line);
 
 void PicoFrameStartSMS(void)
 {
+  struct PicoEState *est = &Pico.est;
   int lines = 192, columns = 256, loffs, coffs;
 
   skip_next_line = 0;
   loffs = screen_offset = 24; // 192 lines is really 224 with top/bottom bars
-  Pico.est.rendstatus = PDRAW_32_COLS;
+  est->rendstatus = PDRAW_32_COLS;
 
   // if mode changes make palette dirty since some modes switch to a fixed one
   if (mode != ((Pico.video.reg[0]&0x06) | (Pico.video.reg[1]&0x18))) {
@@ -753,14 +754,14 @@ void PicoFrameStartSMS(void)
   } else {
     if ((mode & 4) && (Pico.video.reg[0] & 0x20)) {
       // SMS mode 4 with 1st column blanked
-      Pico.est.rendstatus |= PDRAW_SMS_BLANK_1;
+      est->rendstatus |= PDRAW_SMS_BLANK_1;
       columns = 248;
     }
 
     switch (mode) {
     // SMS2 only 224/240 line modes, e.g. Micro Machines
     case 0x06|0x08:
-        Pico.est.rendstatus |= PDRAW_30_ROWS;
+        est->rendstatus |= PDRAW_30_ROWS;
         loffs = screen_offset = 0;
         lines = 240;
         break;
@@ -776,32 +777,34 @@ void PicoFrameStartSMS(void)
   coffs = (FinalizeLineSMS == NULL && columns == 248 ? 8 : 0);
   if (FinalizeLineSMS != NULL && (PicoIn.opt & POPT_EN_SOFTSCALE)) {
     // softscaling always generates 320px, but no scaling in 8bit fast
-    Pico.est.rendstatus |= PDRAW_SOFTSCALE;
+    est->rendstatus |= PDRAW_SOFTSCALE;
     coffs = 0;
     columns = 320;
   } else if (!(PicoIn.opt & POPT_DIS_32C_BORDER)) {
-    Pico.est.rendstatus |= PDRAW_BORDER_32;
+    est->rendstatus |= PDRAW_BORDER_32;
     line_offset -= coffs;
     coffs = (320-columns) / 2;
     if (FinalizeLineSMS == NULL)
       line_offset += coffs; // ... else centering done in FinalizeLine
   }
 
-  if (Pico.est.rendstatus != rendstatus_old || lines != rendlines) {
+  if (est->rendstatus != rendstatus_old || lines != rendlines) {
+    // mode_change() might reset rendstatus_old by calling SetOutFormat
+    int rendstatus = est->rendstatus;
     emu_video_mode_change(loffs, lines, coffs, columns);
-    rendstatus_old = Pico.est.rendstatus;
+    rendstatus_old = rendstatus;
     rendlines = lines;
     sprites = 0;
   }
 
-  Pico.est.HighCol = HighColBase + screen_offset * HighColIncrement;
-  Pico.est.DrawLineDest = (char *)DrawLineDestBase + screen_offset * DrawLineDestIncrement;
+  est->HighCol = HighColBase + screen_offset * HighColIncrement;
+  est->DrawLineDest = (char *)DrawLineDestBase + screen_offset * DrawLineDestIncrement;
 
   if (FinalizeLineSMS == FinalizeLine8bitSMS) {
-    Pico.m.dirtyPal = (Pico.m.dirtyPal || Pico.est.SonicPalCount ? 2 : 0);
-    memcpy(Pico.est.SonicPal, PicoMem.cram, 0x40*2);
+    Pico.m.dirtyPal = (Pico.m.dirtyPal || est->SonicPalCount ? 2 : 0);
+    memcpy(est->SonicPal, PicoMem.cram, 0x40*2);
   }
-  Pico.est.SonicPalCount = 0;
+  est->SonicPalCount = 0;
 }
 
 void PicoParseSATSMS(int line)
-- 
2.39.5