(svn r21517) -Codechange: Add IsGroundVehicle function to the Engine class.

src/engine_base.h

@@ -87,6 +87,15 @@ struct Engine : EnginePool::PoolItem<&_engine_pool> {
 	uint GetDisplayWeight() const;
 	uint GetDisplayMaxTractiveEffort() const;
 	Date GetLifeLengthInDays() const;
+
+	/**
+	 * Check if the engine is a ground vehicle.
+	 * @return True iff the engine is a train or a road vehicle.
+	 */
+	FORCEINLINE bool IsGroundVehicle() const
+	{
+		return this->type == VEH_TRAIN || this->type == VEH_ROAD;
+	}
 };
 
 struct EngineIDMapping {