src/newgrf_cargo.cpp

   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 newgrf_cargo.cpp Implementation of NewGRF cargoes. */
  11
  12 #include "stdafx.h"
  13 #include "debug.h"
  14 #include "newgrf_spritegroup.h"
  15
  16 /** Resolver of cargo. */
  17 struct CargoResolverObject : public ResolverObject {
  18         /**
  19          * Constructor of the cargo resolver.
  20          * @param cs Cargo being resolved.
  21          * @param callback Callback ID.
  22          * @param param1 First parameter (var 10) of the callback.
  23          * @param param2 Second parameter (var 18) of the callback.
  24          */
  25         CargoResolverObject (const CargoSpec *cs, CallbackID callback = CBID_NO_CALLBACK, uint32 param1 = 0, uint32 param2 = 0)
  26                 : ResolverObject (cs->grffile, callback, param1, param2)
  27         {
  28         }
  29
  30         /* virtual */ const SpriteGroup *ResolveReal(const RealSpriteGroup *group) const;
  31 };
  32
  33 /* virtual */ const SpriteGroup *CargoResolverObject::ResolveReal(const RealSpriteGroup *group) const
  34 {
  35         /* Cargo action 2s should always have only 1 "loaded" state, but some
  36          * times things don't follow the spec... */
  37         if (group->num_loaded > 0) return group->loaded[0];
  38         if (group->num_loading > 0) return group->loading[0];
  39
  40         return NULL;
  41 }
  42
  43 static inline const SpriteGroup *CargoResolve (const CargoSpec *cs,
  44         CallbackID callback = CBID_NO_CALLBACK, uint32 param1 = 0, uint32 param2 = 0)
  45 {
  46         CargoResolverObject object (cs, callback, param1, param2);
  47         return SpriteGroup::Resolve (cs->group, object);
  48 }
  49
  50 /**
  51  * Get the custom sprite for the given cargo type.
  52  * @param cs Cargo being queried.
  53  * @return Custom sprite to draw, or \c 0 if not available.
  54  */
  55 SpriteID GetCustomCargoSprite(const CargoSpec *cs)
  56 {
  57         const SpriteGroup *group = CargoResolve (cs);
  58         if (group == NULL) return 0;
  59
  60         return group->GetResult();
  61 }
  62
  63
  64 uint16 GetCargoCallback(CallbackID callback, uint32 param1, uint32 param2, const CargoSpec *cs)
  65 {
  66         return SpriteGroup::CallbackResult (CargoResolve (cs, callback, param1, param2));
  67 }
  68
  69 /**
  70  * Translate a GRF-local cargo slot/bitnum into a CargoID.
  71  * @param cargo   GRF-local cargo slot/bitnum.
  72  * @param grffile Originating GRF file.
  73  * @param usebit  Defines the meaning of \a cargo for GRF version < 7.
  74  *                If true, then \a cargo is a bitnum. If false, then \a cargo is a cargoslot.
  75  *                For GRF version >= 7 \a cargo is always a translated cargo bit.
  76  * @return CargoID or CT_INVALID if the cargo is not available.
  77  */
  78 CargoID GetCargoTranslation(uint8 cargo, const GRFFile *grffile, bool usebit)
  79 {
  80         /* Pre-version 7 uses the 'climate dependent' ID in callbacks and properties, i.e. cargo is the cargo ID */
  81         if (grffile->grf_version < 7 && !usebit) return cargo;
  82
  83         /* Other cases use (possibly translated) cargobits */
  84
  85         if (grffile->cargo_list.Length() > 0) {
  86                 /* ...and the cargo is in bounds, then get the cargo ID for
  87                  * the label */
  88                 if (cargo < grffile->cargo_list.Length()) return GetCargoIDByLabel(grffile->cargo_list[cargo]);
  89         } else {
  90                 /* Else the cargo value is a 'climate independent' 'bitnum' */
  91                 return GetCargoIDByBitnum(cargo);
  92         }
  93         return CT_INVALID;
  94 }