vehicleSubSystems Phase 1: reconstruct + register the cluster-panel family

Reconstruct the whole engineering-screen (MFD) subsystem cluster-panel system in
btl4gau2 (from the Ghidra decomp of BTL4OPT.EXE) and register the vehicleSubSystems
config primitive:

- Sub-gauges: AnimatedSubsystemLamp/AnimatedSourceLamp (OneOfSeveral + cooling/
  power connections), ScalarBarGauge (BarGraphBitMapScalar + generator-voltage
  connection), ConfigMapGauge, plus the 3 file-private GaugeConnection classes
  (@004c3134/31ec/3288 samplers).
- SubsystemCluster base (ctor builds ~11 child gauges across the MFD + engineering
  ports; Execute/dtor/frame-draw/enable helpers) + the 5 subclasses HeatSink/
  Myomer/Weapon/Energy/Ballistic (ctors + Executes).
- VehicleSubSystems::Make dispatcher (@004cbaf0): per-subsystem factory keyed on
  classID (HeatSink 0xBC3 / Myomer 0xBC6 / Energy 0xBC8,0xBD4 / Ballistic
  0xBCD,0xBD0), placed via the 12-row aux-screen geometry table, + registered in
  BTL4MethodDescription[].

SAFE + gated: gauges only build under BT_DEV_GAUGES/pod, and until Phase 2
populates the subsystem aux-screen field (subsystem[0x1dc]) the Make hits its
"aux screen = zero" skip -> combat untouched.  Two minor children deferred as
marked NULLs (SegmentArc270 recharge dial + BitMapInverseWipeScalar eject wipe --
their ctors are btl4gaug placeholders).  Raw-offset subsystem reads (0x1dc/0x1e0/
0x1e4/0x31c/0x334/0x364/0x43c...) marked BEST-EFFORT pending Phase 2.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

game/reconstructed/btl4gau2.hpp

@@ -173,7 +173,7 @@
 		AnimatedSubsystemLamp(					// @004c70a4
 			GaugeRate, ModeMask, L4GaugeRenderer *, int,
 			int x, int y, const char *image, int columns, int rows,
-			Entity *subsystem, const char *identification_string);
+			void *subsystem, const char *identification_string);
 		~AnimatedSubsystemLamp();				// @004c7134
 	protected:
 		int		selected;						// @0xAC  this[0x2B]  (connection dst)
@@ -186,7 +186,7 @@
 		AnimatedSourceLamp(						// @004c7160
 			GaugeRate, ModeMask, L4GaugeRenderer *, int,
 			int x, int y, const char *image, int columns, int rows,
-			Entity *source, const char *identification_string);
+			void *source, const char *identification_string);
 		~AnimatedSourceLamp();					// @004c71f0
 	protected:
 		int		selected;						// @0xAC  this[0x2B]
@@ -202,14 +202,25 @@
 	// Both share dtor FUN_004c733c (chains the bar dtor @00472fb4).  Used with
 	// the strings "GeneratorVoltage(slotOf)" / "GeneratorVoltage(scalar)".
 	//#######################################################################
-	class ScalarBarGauge :						// (best-effort)
+	// ScalarBarGauge chains the MUNGA L4 bar primitive @00472ef0 == the engine
-		public GraphicGauge						// MUNGA L4 bar primitive (FUN_00472ef0); engine has no plain "BarGraph" class
+	// BarGraphBitMapScalar (WipeGaugeScalar).  Its value slot @0xB4 (this[0x2D])
+	// IS the inherited WipeGaugeScalar::currentValue -- the connection writes it,
+	// so NO own field is declared (declaring one would shadow / mis-align).
+	class ScalarBarGauge :
+		public BarGraphBitMapScalar				// @00472ef0 base (WipeGaugeScalar : GraphicGauge)
 	{
 	public:
-		ScalarBarGauge(/* ...bar geometry..., Scalar *value, id */);	// @004c721c / @004c72ac
+		// @004c721c -- the "slotOf" variant: bar body then AddConnection(new
+		// GeneratorVoltageConnection @004c3288) feeding currentValue from a
+		// resolved voltage source.  (The @004c72ac plain-Scalar variant is unused
+		// by the cluster path.)
+		ScalarBarGauge(							// @004c721c
+			GaugeRate, ModeMask, L4GaugeRenderer *, int graphics_port_number,
+			int left, int bottom, int right, int top,
+			const char *tile_image, int foreground_color, int background_color,
+			WipeGaugeScalar::Direction direction, Scalar min, Scalar max,
+			void *voltage_source, const char *identification_string);
 		~ScalarBarGauge();						// @004c733c
-	protected:
-		Scalar	value;							// @0xB4  this[0x2D]  (connection dst)
 	};
 
 
@@ -322,19 +333,24 @@
 		public GraphicGauge
 	{
 	public:
+		// @004c8140.  Binary param order (rate/mode are hardcoded 0xFFFF/0xFFFFFFFF
+		// in the base GraphicGauge ctor; the panel's two bit-plane MODE masks are
+		// mfd_mode (MFD-port children) and eng_mode (engineering-port children)).
 		SubsystemCluster(						// @004c8140
-			GaugeRate, ModeMask, L4GaugeRenderer *, int,
+			ModeMask mfd_mode, L4GaugeRenderer *renderer, int owner_ID,
-			int x, int y, Subsystem *subsystem, GaugeRenderer *eng_renderer,
+			int mfd_port, int x, int y, Subsystem *subsystem, ModeMask eng_mode,
-			const char *port_name, const char *tile_image,
+			const char *eng_port_name, const char *tile_image,
-			const char *background_image, int damage_zone_table,
+			const char *label, char **image_names,
 			const char *identification_string);
 		~SubsystemCluster();					// @004c87dc
 		Logical	TestInstance() const;
 		void	BecameActive();					// @004c88e4 (shared base Execute trampoline)
 		void	Execute();						// @004c88e4
 	protected:
+		BackgroundBitmap
+				*background;					// @0x90  this[0x24]  BackgroundBitmap
 		GraphicGauge
-				*background,					// @0x90  this[0x24]  BackgroundBitmap
+				*generatorVoltageBar,			// @0x94  this[0x25]  ScalarBarGauge (evolt)
 				*temperatureBar,				// @0x98  this[0x26]  HorizTwoPartBar
 				*coolingLoopA,					// @0x9C  this[0x27]  AnimatedSubsystemLamp
 				*coolingLoopB,					// @0xA0  this[0x28]
@@ -347,12 +363,27 @@
 				*leakGauge;						// @0xBC  this[0x2F]  LeakGauge
 		Subsystem *subsystem;					// @0xC0  this[0x30]
 		Logical	operating;						// @0xC4  this[0x31]
+		int		previousDrawState;				// @0xC8  this[0x32]  (Execute repaint key)
+
+		// internal helpers (non-virtual; @004c89c4 / @004c8820 / @004c8a28)
+		void	DrawPanelFrame(int color);		// @004c89c4
+		void	ReleaseChildren();				// @004c8820
+		void	SetChildrenEnable(int enable);	// @004c8a28
+	public:
+		int		GetDrawState();					// @004c8990 (operational-state virtual, vtbl+0x48)
+	protected:
 	};
 
 	class HeatSinkCluster :						// @004c8a6c
 		public SubsystemCluster
 	{
 	public:
+		HeatSinkCluster(						// @004c8a6c
+			ModeMask mfd_mode, L4GaugeRenderer *, int owner_ID, int mfd_port,
+			int x, int y, Subsystem *subsystem, Subsystem *hud, ModeMask eng_mode,
+			const char *eng_port_name, const char *tile_image, const char *label,
+			const char *fail_lamp_image, char **image_names,
+			const char *identification_string);
 		~HeatSinkCluster();						// @004c8d18
 		void	Execute();						// @004c8db0
 	protected:
@@ -368,10 +399,39 @@
 				*heatNumeric;					// @0xEC  this[0x3B]  NumericDisplayScalar
 	};
 
+	//
+	// MyomerCluster @004c8df4 (vtable 00519f88) : SubsystemCluster -- the myomer
+	// (muscle) panel.  Adds a SeekVoltageGraph ("EngrGraph", edestryd.pcc) fed by
+	// an InputVoltage GeneratorVoltageConnection (writes seekValue@0x33) + a
+	// seek-step OneOfSeveralInt (bteseek.pcc, subsys+0x800).  Execute = base.
+	//
+	class MyomerCluster :						// @004c8df4
+		public SubsystemCluster
+	{
+	public:
+		MyomerCluster(							// @004c8df4
+			ModeMask mfd_mode, L4GaugeRenderer *, int owner_ID, int mfd_port,
+			int x, int y, Subsystem *subsystem, ModeMask eng_mode,
+			const char *eng_port_name, const char *tile_image, const char *label,
+			char **image_names, const char *identification_string);
+		~MyomerCluster();						// @004c8f54
+	protected:
+		Scalar	seekValue;						// @0xCC  this[0x33]  (connection dst)
+		GraphicGauge
+				*seekGraph,						// @0xD0  this[0x34]  SeekVoltageGraph
+				*seekStepLamp;					// @0xD4  this[0x35]  OneOfSeveralInt
+	};
+
 	class WeaponCluster :						// @004c8fc4
 		public SubsystemCluster
 	{
 	public:
+		WeaponCluster(							// @004c8fc4
+			ModeMask mfd_mode, L4GaugeRenderer *, int owner_ID, int mfd_port,
+			int x, int y, Subsystem *subsystem, ModeMask eng_mode,
+			const char *eng_port_name, const char *tile_image, const char *label,
+			const char *cluster_image, char **image_names,
+			const char *identification_string);
 		~WeaponCluster();						// @004c91d4
 		void	BecameActive();					// @004c9258
 		void	Execute();						// @004c9290
@@ -390,6 +450,12 @@
 		public WeaponCluster
 	{
 	public:
+		EnergyWeaponCluster(					// @004c93b0
+			ModeMask mfd_mode, L4GaugeRenderer *, int owner_ID, int mfd_port,
+			int x, int y, Subsystem *subsystem, ModeMask eng_mode,
+			const char *eng_port_name, const char *tile_image, const char *label,
+			const char *cluster_image, char **image_names,
+			const char *identification_string);
 		~EnergyWeaponCluster();					// @004c94dc
 	protected:
 		SeekVoltageGraph *seekGraph;			// @0xE8  this[0x3A]
@@ -400,6 +466,13 @@
 		public WeaponCluster
 	{
 	public:
+		BallisticWeaponCluster(					// @004c9558
+			ModeMask mfd_mode, L4GaugeRenderer *, int owner_ID, int mfd_port,
+			int x, int y, Subsystem *subsystem, ModeMask eng_mode,
+			const char *eng_port_name, const char *tile_image, const char *label,
+			const char *cluster_image, char **image_names,
+			const char *font_a, const char *font_b,
+			const char *identification_string);
 		~BallisticWeaponCluster();				// @004c9940
 		void	BecameActive();					// @004c99cc
 		void	Execute();						// @004c9a38
@@ -422,4 +495,24 @@
 				*ammoCountB;					// @0x118 this[0x46]  NumericDisplayInteger
 	};
 
+
+	//#######################################################################
+	// vehicleSubSystems -- the config primitive that builds the engineering-
+	// screen (MFD) subsystem cluster panels.  Make @004cbaf0 (methodDescription
+	// @0x51c080, 8 typeString params = the 8 status strip bitmaps) is a per-
+	// subsystem factory: it walks the mech roster (skipping slot 0), and for each
+	// subsystem builds the right cluster (HeatSink/Myomer/Energy/Ballistic) onto
+	// one of 12 auxiliary MFD positions selected by subsystem[0x1dc] (the aux-
+	// screen position 1..12).  This holder just carries the registered
+	// MethodDescription + the static Make dispatcher (there is no instance).
+	//#######################################################################
+	class VehicleSubSystems
+	{
+	public:
+		static MethodDescription methodDescription;
+		static Logical Make(				// @004cbaf0
+			int display_port_index, Vector2DOf<int> position,
+			Entity *entity, GaugeRenderer *gauge_renderer);
+	};
+
 #endif

game/reconstructed/btl4grnd.cpp

@@ -66,6 +66,7 @@
 #endif
 #if !defined(BTL4GAUG_HPP)
 #	include <btl4gaug.hpp>		// the BT gauge classes (Compass, etc.)
+#	include <btl4gau2.hpp>		// the composite cluster gauges + VehicleSubSystems
 #	include <btl4rdr.hpp>		// MapDisplay (the "map" radar gauge)
 #	include <btl4gau3.hpp>		// PlayerStatus (the comm/score gauge)
 #endif
@@ -141,6 +142,7 @@ MethodDescription
 			&OneOfSeveralPixInt::methodDescription,		// "oneOfSeveralPixInt" -- button-state lamp (duck/light/mode)
 			&MapDisplay::methodDescription,				// "map" -- the radar / tactical display
 			&PlayerStatus::methodDescription,			// "PlayerStatus" -- comm/score name-tag gauge
+			&VehicleSubSystems::methodDescription,		// "vehicleSubSystems" -- engineering-screen subsystem cluster panels
 			&BTL4ChainToPrevious
 		};