Check if programmed vblank is earlier than hardwired vblank in vblank only programmed...

diff --git a/custom.cpp b/custom.cpp
index b03afb439ea3dc58feb5245f688f78755cf2be6d..4c4732f3c9c17a52ce900bd1c28aca5db9100c07 100644 (file)
--- a/custom.cpp
+++ b/custom.cpp
@@ -7096,6 +7096,7 @@ static void init_beamcon0(bool fakehz)
        }
 
        float clk = (float)(currprefs.ntscmode ? CHIPSET_CLOCK_NTSC : CHIPSET_CLOCK_PAL);
+       int hardwired_vsstrt = 0;
        if (!isntsc) {
                maxvpos = MAXVPOS_PAL;
                maxhpos = MAXHPOS_PAL;
@@ -7158,6 +7159,7 @@ static void init_beamcon0(bool fakehz)
        // A1000 Agnus VBSTRT=first line, OCS and later: VBSTRT=last line
        if (agnusa1000) {
                maxvpos_display_vsync++;
+               hardwired_vsstrt++;
        }
 
        vblank_firstline_hw = minfirstline;
@@ -7344,16 +7346,26 @@ static void init_beamcon0(bool fakehz)
                if (vsstrt > 0 && vsstrt < maxvpos / 2) {
                        maxvpos_display_vsync += vsstrt - 1;
                }
+               // if (weird mode where) vblank starts after vsync start+3: minfirstline = vsstrt+3
+               if (currprefs.gfx_overscanmode >= OVERSCANMODE_EXTREME && firstblankedline >= vsstrt + 3 && minfirstline > vsstrt + 3 && firstblankedline < minfirstline) {
+                       minfirstline = vsstrt + 3;
+                       if (minfirstline_hw > minfirstline) {
+                               minfirstline_hw = minfirstline;
+                       }
+               }
        } else if (beamcon0 & bemcon0_vsync_mask) {
                firstblankedline = maxvpos + 1;
        } else if (beamcon0 & BEAMCON0_VARVBEN) {
-               firstblankedline = vbstrt;
-               if (vsstrt > 0 && vsstrt < maxvpos / 2) {
-                       maxvpos_display_vsync += vsstrt - 1;
+               if (minfirstline > vbstop) {
+                       minfirstline = vbstop;
+                       if (minfirstline < 3) {
+                               minfirstline = 3;
+                       }
                }
+               firstblankedline = vbstrt;
                // if (weird mode where) vblank starts after vsync start+3: minfirstline = vsstrt+3
-               if (currprefs.gfx_overscanmode >= OVERSCANMODE_EXTREME && firstblankedline >= vsstrt + 3 && minfirstline > vsstrt + 3 && firstblankedline < minfirstline) {
-                       minfirstline = vsstrt + 3;
+               if (currprefs.gfx_overscanmode >= OVERSCANMODE_EXTREME && firstblankedline >= hardwired_vsstrt + 3 && minfirstline > hardwired_vsstrt + 3 && firstblankedline < minfirstline) {
+                       minfirstline = hardwired_vsstrt + 3;
                        if (minfirstline_hw > minfirstline) {
                                minfirstline_hw = minfirstline;
                        }