OpenTTD
newgrf_canal.cpp
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1 /* $Id: newgrf_canal.cpp 26482 2014-04-23 20:13:33Z rubidium $ */
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 
12 #include "stdafx.h"
13 #include "debug.h"
14 #include "newgrf_spritegroup.h"
15 #include "newgrf_canal.h"
16 #include "water.h"
17 #include "water_map.h"
18 
19 #include "safeguards.h"
20 
23 
27 
29 
30  /* virtual */ uint32 GetRandomBits() const;
31  /* virtual */ uint32 GetVariable(byte variable, uint32 parameter, bool *available) const;
32 };
33 
36  CanalScopeResolver canal_scope;
37 
40 
41  /* virtual */ ScopeResolver *GetScope(VarSpriteGroupScope scope = VSG_SCOPE_SELF, byte relative = 0)
42  {
43  switch (scope) {
44  case VSG_SCOPE_SELF: return &this->canal_scope;
45  default: return ResolverObject::GetScope(scope, relative);
46  }
47  }
48 
49  /* virtual */ const SpriteGroup *ResolveReal(const RealSpriteGroup *group) const;
50 };
51 
52 /* virtual */ uint32 CanalScopeResolver::GetRandomBits() const
53 {
54  /* Return random bits only for water tiles, not station tiles */
55  return IsTileType(this->tile, MP_WATER) ? GetWaterTileRandomBits(this->tile) : 0;
56 }
57 
58 /* virtual */ uint32 CanalScopeResolver::GetVariable(byte variable, uint32 parameter, bool *available) const
59 {
60  switch (variable) {
61  /* Height of tile */
62  case 0x80: {
63  int z = GetTileZ(this->tile);
64  /* Return consistent height within locks */
65  if (IsTileType(this->tile, MP_WATER) && IsLock(this->tile) && GetLockPart(this->tile) == LOCK_PART_UPPER) z--;
66  return z;
67  }
68 
69  /* Terrain type */
70  case 0x81: return GetTerrainType(this->tile);
71 
72  /* Dike map: Connectivity info for river and canal tiles
73  *
74  * Assignment of bits to directions defined in agreement with
75  * http://projects.tt-forums.net/projects/ttdpatch/repository/revisions/2367/entry/trunk/patches/water.asm#L879
76  * 7
77  * 3 0
78  * 6 * 4
79  * 2 1
80  * 5
81  */
82  case 0x82: {
83  uint32 connectivity =
84  (!IsWateredTile(TILE_ADDXY(tile, -1, 0), DIR_SW) << 0) // NE
85  + (!IsWateredTile(TILE_ADDXY(tile, 0, 1), DIR_NW) << 1) // SE
86  + (!IsWateredTile(TILE_ADDXY(tile, 1, 0), DIR_NE) << 2) // SW
87  + (!IsWateredTile(TILE_ADDXY(tile, 0, -1), DIR_SE) << 3) // NW
88  + (!IsWateredTile(TILE_ADDXY(tile, -1, 1), DIR_W) << 4) // E
89  + (!IsWateredTile(TILE_ADDXY(tile, 1, 1), DIR_N) << 5) // S
90  + (!IsWateredTile(TILE_ADDXY(tile, 1, -1), DIR_E) << 6) // W
91  + (!IsWateredTile(TILE_ADDXY(tile, -1, -1), DIR_S) << 7); // N
92  return connectivity;
93  }
94 
95  /* Random data for river or canal tiles, otherwise zero */
96  case 0x83: return IsTileType(this->tile, MP_WATER) ? GetWaterTileRandomBits(this->tile) : 0;
97  }
98 
99  DEBUG(grf, 1, "Unhandled canal variable 0x%02X", variable);
100 
101  *available = false;
102  return UINT_MAX;
103 }
104 
105 
106 /* virtual */ const SpriteGroup *CanalResolverObject::ResolveReal(const RealSpriteGroup *group) const
107 {
108  if (group->num_loaded == 0) return NULL;
109 
110  return group->loaded[0];
111 }
112 
113 CanalScopeResolver::CanalScopeResolver(ResolverObject &ro, TileIndex tile) : ScopeResolver(ro)
114 {
115  this->tile = tile;
116 }
117 
127  CallbackID callback, uint32 callback_param1, uint32 callback_param2)
128  : ResolverObject(_water_feature[feature].grffile, callback, callback_param1, callback_param2), canal_scope(*this, tile)
129 {
130  this->root_spritegroup = _water_feature[feature].group;
131 }
132 
140 {
141  CanalResolverObject object(feature, tile);
142  const SpriteGroup *group = object.Resolve();
143  if (group == NULL) return 0;
144 
145  return group->GetResult();
146 }
147 
157 static uint16 GetCanalCallback(CallbackID callback, uint32 param1, uint32 param2, CanalFeature feature, TileIndex tile)
158 {
159  CanalResolverObject object(feature, tile, callback, param1, param2);
160  return object.ResolveCallback();
161 }
162 
170 uint GetCanalSpriteOffset(CanalFeature feature, TileIndex tile, uint cur_offset)
171 {
172  if (HasBit(_water_feature[feature].callback_mask, CBM_CANAL_SPRITE_OFFSET)) {
173  uint16 cb = GetCanalCallback(CBID_CANALS_SPRITE_OFFSET, cur_offset, 0, feature, tile);
174  if (cb != CALLBACK_FAILED) return cur_offset + cb;
175  }
176  return cur_offset;
177 }