Refactor gpgx init method to use fewer arguments

Upcoming waterbox changes will likely limit the number of arguments a function can take to 6, which should be enough for anybody

src/BizHawk.Emulation.Cores/Consoles/Sega/gpgx64/GPGX.ISettable.cs

@@ -288,7 +288,7 @@ namespace BizHawk.Emulation.Cores.Consoles.Sega.gpgx
 			[DefaultValue((uint)0xffff00ff)]
 			public uint BackdropColor { get; set; }
 
-			public LibGPGX.InitSettings GetNativeSettings()
+			public LibGPGX.InitSettings GetNativeSettings(GameInfo game)
 			{
 				return new LibGPGX.InitSettings
 				{
@@ -299,7 +299,12 @@ namespace BizHawk.Emulation.Cores.Consoles.Sega.gpgx
 					LowGain = (short)(LowGain * 100),
 					MidGain = (short)(MidGain * 100),
 					HighGain = (short)(HighGain * 100),
-					BackdropColor = BackdropColor
+					BackdropColor = BackdropColor,
+					SixButton = UseSixButton,
+					InputSystemA = SystemForSystem(ControlTypeLeft),
+					InputSystemB = SystemForSystem(ControlTypeRight),
+					Region = Region,
+					ForceSram = game["sram"],
 				};
 			}
 

src/BizHawk.Emulation.Cores/Consoles/Sega/gpgx64/GPGX.cs

@@ -81,10 +81,7 @@ namespace BizHawk.Emulation.Cores.Consoles.Sega.gpgx
 				LibGPGX.INPUT_SYSTEM system_a = SystemForSystem(_syncSettings.ControlTypeLeft);
 				LibGPGX.INPUT_SYSTEM system_b = SystemForSystem(_syncSettings.ControlTypeRight);
 
-				var initResult = Core.gpgx_init(
+				var initResult = Core.gpgx_init(romextension, LoadCallback, _syncSettings.GetNativeSettings(game));
-					romextension,
-					LoadCallback, _syncSettings.UseSixButton, system_a, system_b, _syncSettings.Region, game["sram"],
-					_syncSettings.GetNativeSettings());
 
 				if (!initResult)
 					throw new Exception($"{nameof(Core.gpgx_init)}() failed");

src/BizHawk.Emulation.Cores/Consoles/Sega/gpgx64/LibGPGX.cs

@@ -33,6 +33,14 @@ namespace BizHawk.Emulation.Cores.Consoles.Sega.gpgx
 		[StructLayout(LayoutKind.Sequential)]
 		public class InitSettings
 		{
+			public uint BackdropColor;
+			public Region Region;
+			public ushort LowPassRange;
+			public short LowFreq;
+			public short HighFreq;
+			public short LowGain;
+			public short MidGain;
+			public short HighGain;
 			public enum FilterType : byte
 			{
 				None = 0,
@@ -40,20 +48,16 @@ namespace BizHawk.Emulation.Cores.Consoles.Sega.gpgx
 				ThreeBand = 2
 			}
 			public FilterType Filter;
-			public ushort LowPassRange;
+			public INPUT_SYSTEM InputSystemA;
-			public short LowFreq;
+			public INPUT_SYSTEM InputSystemB;
-			public short HighFreq;
+			public bool SixButton;
-			public short LowGain;
+			public bool ForceSram;
-			public short MidGain;
-			public short HighGain;
-			public uint BackdropColor;
 		}
 
 		[BizImport(CallingConvention.Cdecl)]
 		public abstract bool gpgx_init(
 			string feromextension,
 			load_archive_cb feload_archive_cb,
-			bool sixbutton, INPUT_SYSTEM system_a, INPUT_SYSTEM system_b, Region region, bool forcesram,
 			[In]InitSettings settings);
 
 		[BizImport(CallingConvention.Cdecl)]

waterbox/gpgx/cinterface/cinterface.c

@@ -490,25 +490,28 @@ GPGX_EX unsigned gpgx_peek_s68k_bus(unsigned addr)
 
 struct InitSettings
 {
-	uint8_t Filter;
+	uint32_t BackdropColor;
+	int Region;
 	uint16_t LowPassRange;
 	int16_t LowFreq;
 	int16_t HighFreq;
 	int16_t LowGain;
 	int16_t MidGain;
 	int16_t HighGain;
-	uint32_t BackdropColor;
+	uint8_t Filter;
+	char InputSystemA;
+	char InputSystemB;
+	char SixButton;
+	char ForceSram;
 };
 
-GPGX_EX int gpgx_init(
+GPGX_EX int gpgx_init(const char* feromextension,
-	const char *feromextension,
 	ECL_ENTRY int (*feload_archive_cb)(const char *filename, unsigned char *buffer, int maxsize),
-	int sixbutton, char system_a, char system_b, int region, int forcesram,
 	struct InitSettings *settings)
 {
 	_debug_puts("Initializing GPGX native...");
 
-	cinterface_force_sram = forcesram;
+	cinterface_force_sram = settings->ForceSram;
 
 	memset(&bitmap, 0, sizeof(bitmap));
 
@@ -551,7 +554,7 @@ GPGX_EX int gpgx_init(
 
 	/* system options */
 	config.system = 0; /* AUTO */
-	config.region_detect = region; // see loadrom.c
+	config.region_detect = settings->Region; // see loadrom.c
 	config.vdp_mode = 0; /* AUTO */
 	config.master_clock = 0; /* AUTO */
 	config.force_dtack = 0;
@@ -571,8 +574,8 @@ GPGX_EX int gpgx_init(
 	// everything else is auto or master system only
 	// XEA1P is port 1 only
 	// WAYPLAY is both ports at same time only
-	input.system[0] = system_a;
+	input.system[0] = settings->InputSystemA;
-	input.system[1] = system_b;
+	input.system[1] = settings->InputSystemB;
 
 	cinterface_custom_backdrop_color = settings->BackdropColor;
 
@@ -581,7 +584,7 @@ GPGX_EX int gpgx_init(
 	{
 		int i;
 		for (i = 0; i < MAX_INPUTS; i++)
-			config.input[i].padtype = sixbutton ? DEVICE_PAD6B : DEVICE_PAD3B;
+			config.input[i].padtype = settings->SixButton ? DEVICE_PAD6B : DEVICE_PAD3B;
 	}
 
 	if (!load_rom("PRIMARY_ROM"))