(svn r21932) -Document: some tidbits related to vehicles

6 files changed, 79 insertions, 35 deletions

diff --git a/src/effectvehicle_base.h b/src/effectvehicle_base.h
index 11067db61..4cd31988b 100644
--- a/src/effectvehicle_base.h
+++ b/src/effectvehicle_base.h
@@ -23,8 +23,8 @@
  *  - bubbles (industry)
  */
 struct EffectVehicle : public SpecializedVehicle<EffectVehicle, VEH_EFFECT> {
-	uint16 animation_state;
-	byte animation_substate;
+	uint16 animation_state;  ///< State primarily used to change the graphics/behaviour.
+	byte animation_substate; ///< Sub state to time the change of the graphics/behaviour.
 
 	/** We don't want GCC to zero our struct! It already is zeroed and has an index! */
 	EffectVehicle() : SpecializedVehicleBase() {}
@@ -35,6 +35,10 @@ struct EffectVehicle : public SpecializedVehicle<EffectVehicle, VEH_EFFECT> {
 	bool Tick();
 };
 
+/**
+ * Iterate over disaster vehicles.
+ * @param var The variable used to iterate over.
+ */
 #define FOR_ALL_EFFECTVEHICLES(var) FOR_ALL_VEHICLES_OF_TYPE(EffectVehicle, var)
 
 #endif /* EFFECTVEHICLE_BASE_H */
diff --git a/src/saveload/afterload.cpp b/src/saveload/afterload.cpp
index 679b0244f..35a5579ba 100644
--- a/src/saveload/afterload.cpp
+++ b/src/saveload/afterload.cpp
@@ -473,6 +473,11 @@ static uint FixVehicleInclination(Vehicle *v, Direction dir)
 	return 1U << GVF_GOINGUP_BIT;
 }
 
+/**
+ * Perform a (large) amount of savegame conversion *magic* in order to
+ * load older savegames and to fill the caches for various purposes.
+ * @return True iff conversion went without a problem.
+ */
 bool AfterLoadGame()
 {
 	SetSignalHandlers();
diff --git a/src/saveload/oldloader_sl.cpp b/src/saveload/oldloader_sl.cpp
index f6572cd8f..e846c1ce5 100644
--- a/src/saveload/oldloader_sl.cpp
+++ b/src/saveload/oldloader_sl.cpp
@@ -163,6 +163,11 @@ static void FixOldTowns()
 
 static StringID *_old_vehicle_names;
 
+/**
+ * Convert the old style vehicles into something that resembles
+ * the old new style savegames. Then #AfterLoadGame can handle
+ * the rest of the conversion.
+ */
 void FixOldVehicles()
 {
 	Vehicle *v;
@@ -1212,6 +1217,12 @@ static const OldChunks vehicle_chunk[] = {
 	OCL_END()
 };
 
+/**
+ * Load the vehicles of an old style savegame.
+ * @param ls  State (buffer) of the currently loaded game.
+ * @param num The number of vehicles to load.
+ * @return True iff loading went without problems.
+ */
 bool LoadOldVehicle(LoadgameState *ls, int num)
 {
 	/* Read the TTDPatch flags, because we need some info from it */
diff --git a/src/saveload/vehicle_sl.cpp b/src/saveload/vehicle_sl.cpp
index 61dece380..8abcb916b 100644
--- a/src/saveload/vehicle_sl.cpp
+++ b/src/saveload/vehicle_sl.cpp
@@ -22,7 +22,7 @@
 
 #include <map>
 
-/*
+/**
  * Link front and rear multiheaded engines to each other
  * This is done when loading a savegame
  */
diff --git a/src/vehicle.cpp b/src/vehicle.cpp
index d2e4556d4..50aa1c5c5 100644
--- a/src/vehicle.cpp
+++ b/src/vehicle.cpp
@@ -63,7 +63,7 @@ uint16 _returned_mail_refit_capacity; ///< Stores the mail capacity after a refi
 byte _age_cargo_skip_counter;         ///< Skip aging of cargo?
 
 
-/* Initialize the vehicle-pool */
+/** The pool with all our precious vehicles. */
 VehiclePool _vehicle_pool("Vehicle");
 INSTANTIATE_POOL_METHODS(Vehicle)
 
@@ -1805,9 +1805,13 @@ void Vehicle::DeleteUnreachedAutoOrders()
 	}
 }
 
+/**
+ * Prepare everything to begin the loading when arriving at a station.
+ * @pre IsTileType(this->tile, MP_STATION) || this->type == VEH_SHIP.
+ */
 void Vehicle::BeginLoading()
 {
-	assert(IsTileType(tile, MP_STATION) || type == VEH_SHIP);
+	assert(IsTileType(this->tile, MP_STATION) || this->type == VEH_SHIP);
 
 	if (this->current_order.IsType(OT_GOTO_STATION) &&
 			this->current_order.GetDestination() == this->last_station_visited) {
@@ -1854,16 +1858,20 @@ void Vehicle::BeginLoading()
 	this->MarkDirty();
 }
 
+/**
+ * Perform all actions when leaving a station.
+ * @pre this->current_order.IsType(OT_LOADING)
+ */
 void Vehicle::LeaveStation()
 {
-	assert(current_order.IsType(OT_LOADING));
+	assert(this->current_order.IsType(OT_LOADING));
 
 	delete this->cargo_payment;
 
 	/* Only update the timetable if the vehicle was supposed to stop here. */
-	if (current_order.GetNonStopType() != ONSF_STOP_EVERYWHERE) UpdateVehicleTimetable(this, false);
+	if (this->current_order.GetNonStopType() != ONSF_STOP_EVERYWHERE) UpdateVehicleTimetable(this, false);
 
-	current_order.MakeLeaveStation();
+	this->current_order.MakeLeaveStation();
 	Station *st = Station::Get(this->last_station_visited);
 	st->loading_vehicles.remove(this);
 
diff --git a/src/vehicle_base.h b/src/vehicle_base.h
index c5290e770..623f534fb 100644
--- a/src/vehicle_base.h
+++ b/src/vehicle_base.h
@@ -156,27 +156,29 @@ public:
 	int32 lateness_counter;             ///< How many ticks late (or early if negative) this vehicle is.
 	Date timetable_start;               ///< When the vehicle is supposed to start the timetable.
 
-	/* Boundaries for the current position in the world and a next hash link.
-	 * NOSAVE: All of those can be updated with VehiclePositionChanged() */
-	Rect coord;
-	Vehicle *next_hash, **prev_hash;
-	Vehicle *next_new_hash, **prev_new_hash;
-	Vehicle **old_new_hash;
+	Rect coord;                         ///< NOSAVE: Graphical bounding box of the vehicle, i.e. what to redraw on moves.
+
+	Vehicle *next_hash;                 ///< NOSAVE: Next vehicle in the visual location hash.
+	Vehicle **prev_hash;                ///< NOSAVE: Previous vehicle in the visual location hash.
+
+	Vehicle *next_new_hash;             ///< NOSAVE: Next vehicle in the tile location hash.
+	Vehicle **prev_new_hash;            ///< NOSAVE: Previous vehicle in the tile location hash.
+	Vehicle **old_new_hash;             ///< NOSAVE: Cache of the current hash chain.
 
 	SpriteID colourmap;                 ///< NOSAVE: cached colour mapping
 
 	/* Related to age and service time */
-	Year build_year;
+	Year build_year;                    ///< Year the vehicle has been built.
 	Date age;                           ///< Age in days
 	Date max_age;                       ///< Maximum age
-	Date date_of_last_service;
-	Date service_interval;
+	Date date_of_last_service;          ///< Last date the vehicle had a service at a depot.
+	Date service_interval;              ///< The interval for (automatic) servicing; either in days or %.
 	uint16 reliability;                 ///< Reliability.
 	uint16 reliability_spd_dec;         ///< Reliability decrease speed.
 	byte breakdown_ctr;                 ///< Counter for managing breakdown events. @see Vehicle::HandleBreakdown
 	byte breakdown_delay;               ///< Counter for managing breakdown length.
-	byte breakdowns_since_last_service;
-	byte breakdown_chance;
+	byte breakdowns_since_last_service; ///< Counter for the amount of breakdowns.
+	byte breakdown_chance;              ///< Current chance of breakdowns.
 
 	int32 x_pos;                        ///< x coordinate.
 	int32 y_pos;                        ///< y coordinate.
@@ -193,7 +195,7 @@ public:
 	byte z_extent;                      ///< z-extent of vehicle bounding box
 	int8 x_offs;                        ///< x offset for vehicle sprite
 	int8 y_offs;                        ///< y offset for vehicle sprite
-	EngineID engine_type;
+	EngineID engine_type;               ///< The type of engine used for this vehicle.
 
 	TextEffectID fill_percent_te_id;    ///< a text-effect id to a loading indicator object
 	UnitID unitnumber;                  ///< unit number, for display purposes only
@@ -201,16 +203,13 @@ public:
 	uint16 cur_speed;                   ///< current speed
 	byte subspeed;                      ///< fractional speed
 	byte acceleration;                  ///< used by train & aircraft
-	uint32 motion_counter;
-	byte progress;
+	uint32 motion_counter;              ///< counter to occasionally play a vehicle sound.
+	byte progress;                      ///< The percentage (if divided by 256) this vehicle already crossed the tile unit.
 
-	/* for randomized variational spritegroups
-	 * bitmask used to resolve them; parts of it get reseeded when triggers
-	 * of corresponding spritegroups get matched */
-	byte random_bits;
-	byte waiting_triggers;              ///< triggers to be yet matched
+	byte random_bits;                   ///< Bits used for determining which randomized variational spritegroups to use when drawing.
+	byte waiting_triggers;              ///< Triggers to be yet matched before rerandomizing the random bits.
 
-	StationID last_station_visited;
+	StationID last_station_visited;     ///< The last station we stopped at.
 
 	CargoID cargo_type;                 ///< type of cargo this vehicle is carrying
 	byte cargo_subtype;                 ///< Used for livery refits (NewGRF variations)
@@ -228,15 +227,12 @@ public:
 	union {
 		OrderList *list;            ///< Pointer to the order list for this vehicle
 		Order     *old;             ///< Only used during conversion of old save games
-	} orders;
+	} orders;                           ///< The orders currently assigned to the vehicle.
 
 	byte vehicle_flags;                 ///< Used for gradual loading and other miscellaneous things (@see VehicleFlags enum)
 
-	/** Ticks to wait before starting next cycle. */
-	uint16 load_unload_ticks;
-
+	uint16 load_unload_ticks;	          ///< Ticks to wait before starting next cycle.
 	GroupID group_id;                   ///< Index of group Pool array
-
 	byte subtype;                       ///< subtype (Filled with values from #EffectVehicles/#TrainSubTypes/#AircraftSubTypes)
 
 	NewGRFCache grf_cache;              ///< Cache of often used calculated NewGRF values
@@ -736,7 +732,17 @@ public:
 	}
 };
 
+/**
+ * Iterate over all vehicles from a given point.
+ * @param var   The variable used to iterate over.
+ * @param start The vehicle to start the iteration at.
+ */
 #define FOR_ALL_VEHICLES_FROM(var, start) FOR_ALL_ITEMS_FROM(Vehicle, vehicle_index, var, start)
+
+/**
+ * Iterate over all vehicles.
+ * @param var The variable used to iterate over.
+ */
 #define FOR_ALL_VEHICLES(var) FOR_ALL_VEHICLES_FROM(var, 0)
 
 /**
@@ -896,14 +902,19 @@ struct SpecializedVehicle : public Vehicle {
 	}
 };
 
+/**
+ * Iterate over all vehicles of a particular type.
+ * @param name The type of vehicle to iterate over.
+ * @param var  The variable used to iterate over.
+ */
 #define FOR_ALL_VEHICLES_OF_TYPE(name, var) FOR_ALL_ITEMS_FROM(name, vehicle_index, var, 0) if (var->type == name::EXPECTED_TYPE)
 
 /**
  * Disasters, like submarines, skyrangers and their shadows, belong to this class.
  */
 struct DisasterVehicle : public SpecializedVehicle<DisasterVehicle, VEH_DISASTER> {
-	uint16 image_override;
-	VehicleID big_ufo_destroyer_target;
+	SpriteID image_override;            ///< Override for the default disaster vehicle sprite.
+	VehicleID big_ufo_destroyer_target; ///< The big UFO that this destroyer is supposed to bomb.
 
 	/** We don't want GCC to zero our struct! It already is zeroed and has an index! */
 	DisasterVehicle() : SpecializedVehicleBase() {}
@@ -914,6 +925,10 @@ struct DisasterVehicle : public SpecializedVehicle<DisasterVehicle, VEH_DISASTER
 	bool Tick();
 };
 
+/**
+ * Iterate over disaster vehicles.
+ * @param var The variable used to iterate over.
+ */
 #define FOR_ALL_DISASTERVEHICLES(var) FOR_ALL_VEHICLES_OF_TYPE(DisasterVehicle, var)
 
 /** Generates sequence of free UnitID numbers */
@@ -929,6 +944,7 @@ struct FreeUnitIDGenerator {
 	~FreeUnitIDGenerator() { free(this->cache); }
 };
 
+/** Sentinel for an invalid coordinate. */
 static const int32 INVALID_COORD = 0x7fffffff;
 
 #endif /* VEHICLE_BASE_H */