(svn r19756) -Codechange: move UpdateViewport() from Vehicle to SpecializedVehicle in order to improve performance

1 files changed, 17 insertions, 15 deletions

diff --git a/src/vehicle_base.h b/src/vehicle_base.h
index bea248538..ea626a40f 100644
--- a/src/vehicle_base.h
+++ b/src/vehicle_base.h
@@ -318,21 +318,6 @@ public:
 	virtual uint Crash(bool flooded = false);
 
 	/**
-	 * Update vehicle sprite- and position caches
-	 * @param moved Was the vehicle moved?
-	 * @param turned Did the vehicle direction change?
-	 */
-	inline void UpdateViewport(bool moved, bool turned)
-	{
-		extern void VehicleMove(Vehicle *v, bool update_viewport);
-
-		if (turned) this->UpdateDeltaXY(this->direction);
-		SpriteID old_image = this->cur_image;
-		this->cur_image = this->GetImage(this->direction);
-		if (moved || this->cur_image != old_image) VehicleMove(this, true);
-	}
-
-	/**
 	 * Returns the Trackdir on which the vehicle is currently located.
 	 * Works for trains and ships.
 	 * Currently works only sortof for road vehicles, since they have a fuzzy
@@ -661,6 +646,23 @@ struct SpecializedVehicle : public Vehicle {
 		assert(v->type == Type);
 		return (const T *)v;
 	}
+
+	/**
+	 * Update vehicle sprite- and position caches
+	 * @param moved Was the vehicle moved?
+	 * @param turned Did the vehicle direction change?
+	 */
+	FORCEINLINE void UpdateViewport(bool moved, bool turned)
+	{
+		extern void VehicleMove(Vehicle *v, bool update_viewport);
+
+		/* Explicitly choose method to call to prevent vtable dereference -
+		 * it gives ~3% runtime improvements in games with many vehicles */
+		if (turned) ((T *)this)->T::UpdateDeltaXY(this->direction);
+		SpriteID old_image = this->cur_image;
+		this->cur_image = ((T *)this)->T::GetImage(this->direction);
+		if (moved || this->cur_image != old_image) VehicleMove(this, true);
+	}
 };
 
 #define FOR_ALL_VEHICLES_OF_TYPE(name, var) FOR_ALL_ITEMS_FROM(name, vehicle_index, var, 0) if (var->type == name::EXPECTED_TYPE)