Cache the last vehicle in a consist to have a visual effect

src/vehicle_base.h

@@ -130,12 +130,20 @@ enum GroundVehicleSubtypeFlags {
 	GVSF_VIRTUAL          = 6, ///< Used for virtual trains during template design, it is needed to skip checks for tile or depot status
 };
 
+/**
+ * Enum to handle vehicle cache flags.
+ */
+enum VehicleCacheFlags {
+	VCF_LAST_VISUAL_EFFECT      = 0, ///< Last vehicle in the consist with a visual effect.
+};
+
 /** Cached often queried values common to all vehicles. */
 struct VehicleCache {
 	uint16 cached_max_speed;        ///< Maximum speed of the consist (minimum of the max speed of all vehicles in the consist).
 	uint16 cached_cargo_age_period; ///< Number of ticks before carried cargo is aged.
 
 	byte cached_vis_effect;  ///< Visual effect to show (see #VisualEffect)
+	byte cached_veh_flags;   ///< Vehicle cache flags (see #VehicleCacheFlags)
 };
 
 /** Sprite sequence for a vehicle part. */