1 /*
2 * This file is part of OpenTTD.
3 * 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.
4 * 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.
5 * 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/>.
6 */
7
8 /** @file newgrf_canal.cpp Implementation of NewGRF canals. */
9
10 #include "stdafx.h"
11 #include "debug.h"
12 #include "newgrf_spritegroup.h"
13 #include "newgrf_canal.h"
14 #include "water.h"
15 #include "water_map.h"
16 #include "spritecache.h"
17
18 #include "safeguards.h"
19
20 /** Table of canal 'feature' sprite groups */
21 WaterFeature _water_feature[CF_END];
22
23 /** Scope resolver of a canal tile. */
24 struct CanalScopeResolver : public ScopeResolver {
25 TileIndex tile; ///< Tile containing the canal.
26
CanalScopeResolverCanalScopeResolver27 CanalScopeResolver(ResolverObject &ro, TileIndex tile)
28 : ScopeResolver(ro), tile(tile)
29 {
30 }
31
32 uint32 GetRandomBits() const override;
33 uint32 GetVariable(byte variable, uint32 parameter, bool *available) const override;
34 };
35
36 /** Resolver object for canals. */
37 struct CanalResolverObject : public ResolverObject {
38 CanalScopeResolver canal_scope;
39 CanalFeature feature;
40
41 CanalResolverObject(CanalFeature feature, TileIndex tile,
42 CallbackID callback = CBID_NO_CALLBACK, uint32 callback_param1 = 0, uint32 callback_param2 = 0);
43
GetScopeCanalResolverObject44 ScopeResolver *GetScope(VarSpriteGroupScope scope = VSG_SCOPE_SELF, byte relative = 0) override
45 {
46 switch (scope) {
47 case VSG_SCOPE_SELF: return &this->canal_scope;
48 default: return ResolverObject::GetScope(scope, relative);
49 }
50 }
51
52 GrfSpecFeature GetFeature() const override;
53 uint32 GetDebugID() const override;
54 };
55
GetRandomBits() const56 /* virtual */ uint32 CanalScopeResolver::GetRandomBits() const
57 {
58 /* Return random bits only for water tiles, not station tiles */
59 return IsTileType(this->tile, MP_WATER) ? GetWaterTileRandomBits(this->tile) : 0;
60 }
61
GetVariable(byte variable,uint32 parameter,bool * available) const62 /* virtual */ uint32 CanalScopeResolver::GetVariable(byte variable, uint32 parameter, bool *available) const
63 {
64 switch (variable) {
65 /* Height of tile */
66 case 0x80: {
67 int z = GetTileZ(this->tile);
68 /* Return consistent height within locks */
69 if (IsTileType(this->tile, MP_WATER) && IsLock(this->tile) && GetLockPart(this->tile) == LOCK_PART_UPPER) z--;
70 return z;
71 }
72
73 /* Terrain type */
74 case 0x81: return GetTerrainType(this->tile);
75
76 /* Dike map: Connectivity info for river and canal tiles
77 *
78 * Assignment of bits to directions defined in agreement with
79 * http://projects.tt-forums.net/projects/ttdpatch/repository/revisions/2367/entry/trunk/patches/water.asm#L879
80 * 7
81 * 3 0
82 * 6 * 4
83 * 2 1
84 * 5
85 */
86 case 0x82: {
87 uint32 connectivity =
88 (!IsWateredTile(TILE_ADDXY(tile, -1, 0), DIR_SW) << 0) // NE
89 + (!IsWateredTile(TILE_ADDXY(tile, 0, 1), DIR_NW) << 1) // SE
90 + (!IsWateredTile(TILE_ADDXY(tile, 1, 0), DIR_NE) << 2) // SW
91 + (!IsWateredTile(TILE_ADDXY(tile, 0, -1), DIR_SE) << 3) // NW
92 + (!IsWateredTile(TILE_ADDXY(tile, -1, 1), DIR_W) << 4) // E
93 + (!IsWateredTile(TILE_ADDXY(tile, 1, 1), DIR_N) << 5) // S
94 + (!IsWateredTile(TILE_ADDXY(tile, 1, -1), DIR_E) << 6) // W
95 + (!IsWateredTile(TILE_ADDXY(tile, -1, -1), DIR_S) << 7); // N
96 return connectivity;
97 }
98
99 /* Random data for river or canal tiles, otherwise zero */
100 case 0x83: return IsTileType(this->tile, MP_WATER) ? GetWaterTileRandomBits(this->tile) : 0;
101 }
102
103 Debug(grf, 1, "Unhandled canal variable 0x{:02X}", variable);
104
105 *available = false;
106 return UINT_MAX;
107 }
108
GetFeature() const109 GrfSpecFeature CanalResolverObject::GetFeature() const
110 {
111 return GSF_CANALS;
112 }
113
GetDebugID() const114 uint32 CanalResolverObject::GetDebugID() const
115 {
116 return this->feature;
117 }
118
119 /**
120 * Canal resolver constructor.
121 * @param feature Which canal feature we want.
122 * @param tile Tile index of canal.
123 * @param callback Callback ID.
124 * @param callback_param1 First parameter (var 10) of the callback.
125 * @param callback_param2 Second parameter (var 18) of the callback.
126 */
CanalResolverObject(CanalFeature feature,TileIndex tile,CallbackID callback,uint32 callback_param1,uint32 callback_param2)127 CanalResolverObject::CanalResolverObject(CanalFeature feature, TileIndex tile,
128 CallbackID callback, uint32 callback_param1, uint32 callback_param2)
129 : ResolverObject(_water_feature[feature].grffile, callback, callback_param1, callback_param2), canal_scope(*this, tile), feature(feature)
130 {
131 this->root_spritegroup = _water_feature[feature].group;
132 }
133
134 /**
135 * Lookup the base sprite to use for a canal.
136 * @param feature Which canal feature we want.
137 * @param tile Tile index of canal, if appropriate.
138 * @return Base sprite returned by GRF, or \c 0 if none.
139 */
GetCanalSprite(CanalFeature feature,TileIndex tile)140 SpriteID GetCanalSprite(CanalFeature feature, TileIndex tile)
141 {
142 CanalResolverObject object(feature, tile);
143 const SpriteGroup *group = object.Resolve();
144 if (group == nullptr) return 0;
145
146 return group->GetResult();
147 }
148
149 /**
150 * Run a specific callback for canals.
151 * @param callback Callback ID.
152 * @param param1 Callback parameter 1.
153 * @param param2 Callback parameter 2.
154 * @param feature For which feature to run the callback.
155 * @param tile Tile index of canal.
156 * @return Callback result or #CALLBACK_FAILED if the callback failed.
157 */
GetCanalCallback(CallbackID callback,uint32 param1,uint32 param2,CanalFeature feature,TileIndex tile)158 static uint16 GetCanalCallback(CallbackID callback, uint32 param1, uint32 param2, CanalFeature feature, TileIndex tile)
159 {
160 CanalResolverObject object(feature, tile, callback, param1, param2);
161 return object.ResolveCallback();
162 }
163
164 /**
165 * Get the new sprite offset for a water tile.
166 * @param tile Tile index of the canal/water tile.
167 * @param feature For which feature to get the new sprite offset.
168 * @param cur_offset Current sprite offset.
169 * @return New sprite offset.
170 */
GetCanalSpriteOffset(CanalFeature feature,TileIndex tile,uint cur_offset)171 uint GetCanalSpriteOffset(CanalFeature feature, TileIndex tile, uint cur_offset)
172 {
173 if (HasBit(_water_feature[feature].callback_mask, CBM_CANAL_SPRITE_OFFSET)) {
174 uint16 cb = GetCanalCallback(CBID_CANALS_SPRITE_OFFSET, cur_offset, 0, feature, tile);
175 if (cb != CALLBACK_FAILED) return cur_offset + cb;
176 }
177 return cur_offset;
178 }
179