fix #3917

[genesisplusgx] "VDP mode" option (for eliminate region lockups / megakey behavior) #3917
TASEmulators · May 27, 2024 · c65a11e · c65a11e
1 parent 0f20bff
commit c65a11e
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Showing 4 changed files with 17 additions and 2 deletions.
diff --git a/Assets/dll/gpgx.wbx.zst b/Assets/dll/gpgx.wbx.zst
diff --git a/src/BizHawk.Emulation.Cores/Consoles/Sega/gpgx64/GPGX.ISettable.cs b/src/BizHawk.Emulation.Cores/Consoles/Sega/gpgx64/GPGX.ISettable.cs
@@ -263,6 +263,11 @@ public class GPGXSyncSettings
 			[DefaultValue(LibGPGX.Region.Autodetect)]
 			public LibGPGX.Region Region { get; set; }
 
+			[DisplayName("Force VDP Mode")]
+			[Description("Overrides the VDP mode to force it to run at either 60Hz (NTSC) or 50Hz (PAL), regardless of system region.")]
+			[DefaultValue(LibGPGX.ForceVDP.Disabled)]
+			public LibGPGX.ForceVDP ForceVDP { get; set; }
+
 			[DisplayName("Load BIOS")]
 			[Description("Indicates whether to load the system BIOS rom.")]
 			[DefaultValue(false)]
@@ -349,6 +354,7 @@ public LibGPGX.InitSettings GetNativeSettings(GameInfo game)
 					InputSystemA = SystemForSystem(ControlTypeLeft),
 					InputSystemB = SystemForSystem(ControlTypeRight),
 					Region = Region,
+					ForceVDP = ForceVDP,
 					LoadBIOS = LoadBIOS,
 					ForceSram = game["sram"],
 					SMSFMSoundChip = SMSFMSoundChip,

diff --git a/src/BizHawk.Emulation.Cores/Consoles/Sega/gpgx64/LibGPGX.cs b/src/BizHawk.Emulation.Cores/Consoles/Sega/gpgx64/LibGPGX.cs
@@ -30,11 +30,19 @@ public enum Region : int
 			Japan_PAL = 4
 		}
 
+		public enum ForceVDP : int
+		{
+			Disabled = 0,
+			NTSC = 1,
+			PAL = 2
+		}
+
 		[StructLayout(LayoutKind.Sequential)]
 		public struct InitSettings
 		{
 			public uint BackdropColor;
 			public Region Region;
+			public ForceVDP ForceVDP;
 			public ushort LowPassRange;
 			public short LowFreq;
 			public short HighFreq;

diff --git a/waterbox/gpgx/cinterface/cinterface.c b/waterbox/gpgx/cinterface/cinterface.c
@@ -715,6 +715,7 @@ struct InitSettings
 {
 	uint32_t BackdropColor;
 	int32_t Region;
+	int32_t ForceVDP;
 	uint16_t LowPassRange;
 	int16_t LowFreq;
 	int16_t HighFreq;
@@ -917,8 +918,8 @@ GPGX_EX int gpgx_init(const char* feromextension,
 
 	/* system options */
 	config.system         = 0; /* = AUTO (or SYSTEM_SG, SYSTEM_SGII, SYSTEM_SGII_RAM_EXT, SYSTEM_MARKIII, SYSTEM_SMS, SYSTEM_SMS2, SYSTEM_GG, SYSTEM_MD) */
-	config.region_detect  = settings->Region; /* = AUTO (1 = USA, 2 = EUROPE, 3 = JAPAN/NTSC, 4 = JAPAN/PAL) */
-	config.vdp_mode       = 0; /* = AUTO (1 = NTSC, 2 = PAL) */
+	config.region_detect  = settings->Region; /* 0 = AUTO, 1 = USA, 2 = EUROPE, 3 = JAPAN/NTSC, 4 = JAPAN/PAL */
+	config.vdp_mode       = settings->ForceVDP; /* 0 = AUTO, 1 = NTSC, 2 = PAL */
 	config.master_clock   = 0; /* = AUTO (1 = NTSC, 2 = PAL) */
 	config.force_dtack    = 0;
 	config.addr_error     = 1;