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         CargoResolverObject(const CargoSpec *cs, CallbackID callback = CBID_NO_CALLBACK, uint32 callback_param1 = 0, uint32 callback_param2 = 0);
  19
  20         /* virtual */ const SpriteGroup *ResolveReal(const RealSpriteGroup *group) const;
  21 };
  22
  23 /* virtual */ const SpriteGroup *CargoResolverObject::ResolveReal(const RealSpriteGroup *group) const
  24 {
  25         /* Cargo action 2s should always have only 1 "loaded" state, but some
  26          * times things don't follow the spec... */
  27         if (group->num_loaded > 0) return group->loaded[0];
  28         if (group->num_loading > 0) return group->loading[0];
  29
  30         return NULL;
  31 }
  32
  33 /**
  34  * Constructor of the cargo resolver.
  35  * @param cs Cargo being resolved.
  36  * @param callback Callback ID.
  37  * @param callback_param1 First parameter (var 10) of the callback.
  38  * @param callback_param2 Second parameter (var 18) of the callback.
  39  */
  40 CargoResolverObject::CargoResolverObject(const CargoSpec *cs, CallbackID callback, uint32 callback_param1, uint32 callback_param2)
  41                 : ResolverObject(cs->grffile, callback, callback_param1, callback_param2)
  42 {
  43         this->root_spritegroup = cs->group;
  44 }
  45
  46 /**
  47  * Get the custom sprite for the given cargo type.
  48  * @param cs Cargo being queried.
  49  * @return Custom sprite to draw, or \c 0 if not available.
  50  */
  51 SpriteID GetCustomCargoSprite(const CargoSpec *cs)
  52 {
  53         CargoResolverObject object(cs);
  54         const SpriteGroup *group = object.Resolve();
  55         if (group == NULL) return 0;
  56
  57         return group->GetResult();
  58 }
  59
  60
  61 uint16 GetCargoCallback(CallbackID callback, uint32 param1, uint32 param2, const CargoSpec *cs)
  62 {
  63         CargoResolverObject object(cs, callback, param1, param2);
  64         return object.ResolveCallback();
  65 }
  66
  67 /**
  68  * Translate a GRF-local cargo slot/bitnum into a CargoID.
  69  * @param cargo   GRF-local cargo slot/bitnum.
  70  * @param grffile Originating GRF file.
  71  * @param usebit  Defines the meaning of \a cargo for GRF version < 7.
  72  *                If true, then \a cargo is a bitnum. If false, then \a cargo is a cargoslot.
  73  *                For GRF version >= 7 \a cargo is always a translated cargo bit.
  74  * @return CargoID or CT_INVALID if the cargo is not available.
  75  */
  76 CargoID GetCargoTranslation(uint8 cargo, const GRFFile *grffile, bool usebit)
  77 {
  78         /* Pre-version 7 uses the 'climate dependent' ID in callbacks and properties, i.e. cargo is the cargo ID */
  79         if (grffile->grf_version < 7 && !usebit) return cargo;
  80
  81         /* Other cases use (possibly translated) cargobits */
  82
  83         if (grffile->cargo_list.Length() > 0) {
  84                 /* ...and the cargo is in bounds, then get the cargo ID for
  85                  * the label */
  86                 if (cargo < grffile->cargo_list.Length()) return GetCargoIDByLabel(grffile->cargo_list[cargo]);
  87         } else {
  88                 /* Else the cargo value is a 'climate independent' 'bitnum' */
  89                 return GetCargoIDByBitnum(cargo);
  90         }
  91         return CT_INVALID;
  92 }