(svn r22205) -Codechange: replace magic number with constant

5 files changed, 11 insertions, 8 deletions

diff --git a/src/articulated_vehicles.cpp b/src/articulated_vehicles.cpp
index 95ec4871a..0ef4d9bc4 100644
--- a/src/articulated_vehicles.cpp
+++ b/src/articulated_vehicles.cpp
@@ -328,7 +328,7 @@ void AddArticulatedParts(Vehicle *first)
 				v = rv;
 
 				rv->subtype = 0;
-				gcache->cached_veh_length = 8; // Callback is called when the consist is finished
+				gcache->cached_veh_length = VEHICLE_LENGTH; // Callback is called when the consist is finished
 				rv->state = RVSB_IN_DEPOT;
 
 				rv->roadtype = front->roadtype;
diff --git a/src/ground_vehicle.hpp b/src/ground_vehicle.hpp
index 6beb4e8fd..941ddca15 100644
--- a/src/ground_vehicle.hpp
+++ b/src/ground_vehicle.hpp
@@ -42,7 +42,7 @@ struct GroundVehicleCache {
 	/* Cached NewGRF values, recalculated on load and each time a vehicle is added to/removed from the consist. */
 	uint16 cached_total_length;     ///< Length of the whole vehicle (valid only for the first engine).
 	EngineID first_engine;          ///< Cached EngineID of the front vehicle. INVALID_ENGINE for the front vehicle itself.
-	uint8 cached_veh_length;        ///< Length of this vehicle in units of 1/8 of normal length. It is cached because this can be set by a callback.
+	uint8 cached_veh_length;        ///< Length of this vehicle in units of 1/VEHICLE_LENGTH of normal length. It is cached because this can be set by a callback.
 
 	/* Cached UI information. */
 	uint16 last_speed;              ///< The last speed we did display, so we only have to redraw when this changes.
diff --git a/src/roadveh_cmd.cpp b/src/roadveh_cmd.cpp
index 29e47bd92..69c1a555d 100644
--- a/src/roadveh_cmd.cpp
+++ b/src/roadveh_cmd.cpp
@@ -100,7 +100,7 @@ int RoadVehicle::GetDisplayImageWidth(Point *offset) const
 		offset->x = reference_width / 2;
 		offset->y = 0;
 	}
-	return this->gcache.cached_veh_length * reference_width / 8;
+	return this->gcache.cached_veh_length * reference_width / VEHICLE_LENGTH;
 }
 
 static SpriteID GetRoadVehIcon(EngineID engine)
@@ -161,11 +161,11 @@ void DrawRoadVehEngine(int left, int right, int preferred_x, int y, EngineID eng
  */
 static uint GetRoadVehLength(const RoadVehicle *v)
 {
-	uint length = 8;
+	uint length = VEHICLE_LENGTH;
 
 	uint16 veh_len = GetVehicleCallback(CBID_VEHICLE_LENGTH, 0, 0, v->engine_type, v);
 	if (veh_len != CALLBACK_FAILED) {
-		length -= Clamp(veh_len, 0, 7);
+		length -= Clamp(veh_len, 0, VEHICLE_LENGTH - 1);
 	}
 
 	return length;
@@ -262,7 +262,7 @@ CommandCost CmdBuildRoadVehicle(TileIndex tile, DoCommandFlag flags, const Engin
 
 		v->roadtype = HasBit(e->info.misc_flags, EF_ROAD_TRAM) ? ROADTYPE_TRAM : ROADTYPE_ROAD;
 		v->compatible_roadtypes = RoadTypeToRoadTypes(v->roadtype);
-		v->gcache.cached_veh_length = 8;
+		v->gcache.cached_veh_length = VEHICLE_LENGTH;
 
 		if (e->flags & ENGINE_EXCLUSIVE_PREVIEW) SetBit(v->vehicle_flags, VF_BUILT_AS_PROTOTYPE);
 
diff --git a/src/train_cmd.cpp b/src/train_cmd.cpp
index 05ce1aaad..853c0ee58 100644
--- a/src/train_cmd.cpp
+++ b/src/train_cmd.cpp
@@ -240,7 +240,7 @@ void Train::ConsistChanged(bool same_length)
 			veh_len = GetVehicleCallback(CBID_VEHICLE_LENGTH, 0, 0, u->engine_type, u);
 		}
 		if (veh_len == CALLBACK_FAILED) veh_len = rvi_u->shorten_factor;
-		veh_len = 8 - Clamp(veh_len, 0, 7);
+		veh_len = VEHICLE_LENGTH - Clamp(veh_len, 0, VEHICLE_LENGTH - 1);
 
 		/* verify length hasn't changed */
 		if (same_length && veh_len != u->gcache.cached_veh_length) RailVehicleLengthChanged(u);
@@ -461,7 +461,7 @@ int Train::GetDisplayImageWidth(Point *offset) const
 		offset->x = reference_width / 2;
 		offset->y = vehicle_pitch;
 	}
-	return this->gcache.cached_veh_length * reference_width / 8;
+	return this->gcache.cached_veh_length * reference_width / VEHICLE_LENGTH;
 }
 
 static SpriteID GetDefaultTrainSprite(uint8 spritenum, Direction direction)
diff --git a/src/vehicle_type.h b/src/vehicle_type.h
index 4b4150a63..32c79421d 100644
--- a/src/vehicle_type.h
+++ b/src/vehicle_type.h
@@ -67,6 +67,9 @@ enum DepotCommand {
 static const uint MAX_LENGTH_VEHICLE_NAME_CHARS  =  32; ///< The maximum length of a vehicle name in characters including '\0'
 static const uint MAX_LENGTH_VEHICLE_NAME_PIXELS = 150; ///< The maximum length of a vehicle name in pixels
 
+/** The length of a vehicle in tile units. */
+static const uint VEHICLE_LENGTH = 8;
+
 /** Vehicle acceleration models. */
 enum AccelerationModel {
 	AM_ORIGINAL,