src/subsidy_base.h

   1 /* $Id$ */
   2
   3 /*
   4  * This file is part of OpenTTD.
   5  * OpenTTD is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, version 2.
   6  * OpenTTD is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
   7  * See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with OpenTTD. If not, see <http://www.gnu.org/licenses/>.
   8  */
   9
  10 /** @file subsidy_base.h %Subsidy base class. */
  11
  12 #ifndef SUBSIDY_BASE_H
  13 #define SUBSIDY_BASE_H
  14
  15 #include "cargo_type.h"
  16 #include "company_type.h"
  17 #include "subsidy_type.h"
  18 #include "core/pool_type.hpp"
  19
  20 typedef Pool<Subsidy, SubsidyID, 1, 256> SubsidyPool;
  21 extern SubsidyPool _subsidy_pool;
  22
  23 /** Struct about subsidies, offered and awarded */
  24 struct Subsidy : SubsidyPool::PoolItem<&_subsidy_pool> {
  25         CargoID cargo_type;      ///< Cargo type involved in this subsidy, CT_INVALID for invalid subsidy
  26         byte remaining;          ///< Remaining months when this subsidy is valid
  27         CompanyByte awarded;     ///< Subsidy is awarded to this company; INVALID_COMPANY if it's not awarded to anyone
  28         SourceTypeByte src_type; ///< Source of subsidised path (ST_INDUSTRY or ST_TOWN)
  29         SourceTypeByte dst_type; ///< Destination of subsidised path (ST_INDUSTRY or ST_TOWN)
  30         SourceID src;            ///< Index of source. Either TownID or IndustryID
  31         SourceID dst;            ///< Index of destination. Either TownID or IndustryID
  32
  33         /**
  34          * We need an (empty) constructor so struct isn't zeroed (as C++ standard states)
  35          */
  36         inline Subsidy() { }
  37
  38         /**
  39          * (Empty) destructor has to be defined else operator delete might be called with NULL parameter
  40          */
  41         inline ~Subsidy() { }
  42
  43         /**
  44          * Tests whether this subsidy has been awarded to someone
  45          * @return is this subsidy awarded?
  46          */
  47         inline bool IsAwarded() const
  48         {
  49                 return this->awarded != INVALID_COMPANY;
  50         }
  51
  52         void AwardTo(CompanyID company);
  53 };
  54
  55 /** Constants related to subsidies */
  56 static const uint SUBSIDY_OFFER_MONTHS         =  12; ///< Duration of subsidy offer
  57 static const uint SUBSIDY_CONTRACT_MONTHS      =  12; ///< Duration of subsidy after awarding
  58 static const uint SUBSIDY_PAX_MIN_POPULATION   = 400; ///< Min. population of towns for subsidised pax route
  59 static const uint SUBSIDY_CARGO_MIN_POPULATION = 900; ///< Min. population of destination town for cargo route
  60 static const uint SUBSIDY_MAX_PCT_TRANSPORTED  =  42; ///< Subsidy will be created only for towns/industries with less % transported
  61 static const uint SUBSIDY_MAX_DISTANCE         =  70; ///< Max. length of subsidised route (DistanceManhattan)
  62
  63 #define FOR_ALL_SUBSIDIES_FROM(var, start) FOR_ALL_ITEMS_FROM(Subsidy, subsidy_index, var, start)
  64 #define FOR_ALL_SUBSIDIES(var) FOR_ALL_SUBSIDIES_FROM(var, 0)
  65
  66 #endif /* SUBSIDY_BASE_H */