newgrf_canal.cpp

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00001 /* $Id: newgrf_canal.cpp 24693 2012-11-10 20:46:39Z alberth $ */
00002 
00003 /*
00004  * This file is part of OpenTTD.
00005  * 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.
00006  * 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.
00007  * 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/>.
00008  */
00009 
00012 #include "stdafx.h"
00013 #include "debug.h"
00014 #include "newgrf_spritegroup.h"
00015 #include "newgrf_canal.h"
00016 #include "water_map.h"
00017 
00019 WaterFeature _water_feature[CF_END];
00020 
00022 struct CanalScopeResolver : public ScopeResolver {
00023   TileIndex tile; 
00024 
00025   CanalScopeResolver(ResolverObject *ro, TileIndex tile);
00026 
00027   /* virtual */ uint32 GetRandomBits() const;
00028   /* virtual */ uint32 GetVariable(byte variable, uint32 parameter, bool *available) const;
00029 };
00030 
00032 struct CanalResolverObject : public ResolverObject {
00033   CanalScopeResolver canal_scope;
00034 
00035   CanalResolverObject(const GRFFile *grffile, TileIndex tile,
00036       CallbackID callback = CBID_NO_CALLBACK, uint32 callback_param1 = 0, uint32 callback_param2 = 0);
00037 
00038   /* virtual */ ScopeResolver *GetScope(VarSpriteGroupScope scope = VSG_SCOPE_SELF, byte relative = 0)
00039   {
00040     switch (scope) {
00041       case VSG_SCOPE_SELF: return &this->canal_scope;
00042       default: return ResolverObject::GetScope(scope, relative);
00043     }
00044   }
00045 
00046   /* virtual */ const SpriteGroup *ResolveReal(const RealSpriteGroup *group) const;
00047 };
00048 
00049 /* virtual */ uint32 CanalScopeResolver::GetRandomBits() const
00050 {
00051   /* Return random bits only for water tiles, not station tiles */
00052   return IsTileType(this->tile, MP_WATER) ? GetWaterTileRandomBits(this->tile) : 0;
00053 }
00054 
00055 /* virtual */ uint32 CanalScopeResolver::GetVariable(byte variable, uint32 parameter, bool *available) const
00056 {
00057   switch (variable) {
00058     /* Height of tile */
00059     case 0x80: {
00060       int z = GetTileZ(this->tile);
00061       /* Return consistent height within locks */
00062       if (IsTileType(this->tile, MP_WATER) && IsLock(this->tile) && GetLockPart(this->tile) == LOCK_PART_UPPER) z--;
00063       return z;
00064     }
00065 
00066     /* Terrain type */
00067     case 0x81: return GetTerrainType(this->tile);
00068 
00069     /* Random data for river or canal tiles, otherwise zero */
00070     case 0x83: return IsTileType(this->tile, MP_WATER) ? GetWaterTileRandomBits(this->tile) : 0;
00071   }
00072 
00073   DEBUG(grf, 1, "Unhandled canal variable 0x%02X", variable);
00074 
00075   *available = false;
00076   return UINT_MAX;
00077 }
00078 
00079 
00080 /* virtual */ const SpriteGroup *CanalResolverObject::ResolveReal(const RealSpriteGroup *group) const
00081 {
00082   if (group->num_loaded == 0) return NULL;
00083 
00084   return group->loaded[0];
00085 }
00086 
00087 CanalScopeResolver::CanalScopeResolver(ResolverObject *ro, TileIndex tile) : ScopeResolver(ro)
00088 {
00089   this->tile = tile;
00090 }
00091 
00100 CanalResolverObject::CanalResolverObject(const GRFFile *grffile, TileIndex tile,
00101     CallbackID callback, uint32 callback_param1, uint32 callback_param2)
00102     : ResolverObject(grffile, callback, callback_param1, callback_param2), canal_scope(this, tile)
00103 {
00104 }
00105 
00112 SpriteID GetCanalSprite(CanalFeature feature, TileIndex tile)
00113 {
00114   CanalResolverObject object(_water_feature[feature].grffile, tile);
00115   const SpriteGroup *group = SpriteGroup::Resolve(_water_feature[feature].group, &object);
00116   if (group == NULL) return 0;
00117 
00118   return group->GetResult();
00119 }
00120 
00130 static uint16 GetCanalCallback(CallbackID callback, uint32 param1, uint32 param2, CanalFeature feature, TileIndex tile)
00131 {
00132   CanalResolverObject object(_water_feature[feature].grffile, tile, callback, param1, param2);
00133   const SpriteGroup *group = SpriteGroup::Resolve(_water_feature[feature].group, &object);
00134   if (group == NULL) return CALLBACK_FAILED;
00135 
00136   return group->GetCallbackResult();
00137 }
00138 
00146 uint GetCanalSpriteOffset(CanalFeature feature, TileIndex tile, uint cur_offset)
00147 {
00148   if (HasBit(_water_feature[feature].callback_mask, CBM_CANAL_SPRITE_OFFSET)) {
00149     uint16 cb = GetCanalCallback(CBID_CANALS_SPRITE_OFFSET, cur_offset, 0, feature, tile);
00150     if (cb != CALLBACK_FAILED) return cur_offset + cb;
00151   }
00152   return cur_offset;
00153 }