Codechange: Return pair from instead of optional out parameter. (#13166)
[openttd-github.git] / src / newgrf_town.h
blobb8bdb1f061ac104457986e1f1c4af68abc5386fe
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 */
8 /** @file newgrf_town.h Functions to handle the town part of NewGRF towns. */
10 #ifndef NEWGRF_TOWN_H
11 #define NEWGRF_TOWN_H
13 #include "town_type.h"
14 #include "newgrf_spritegroup.h"
16 /**
17 * Scope resolver for a town.
18 * @note Currently there is no direct town resolver; we only need to get town
19 * variable results from inside stations, house tiles and industries,
20 * and to check the town's persistent storage.
22 struct TownScopeResolver : public ScopeResolver {
23 Town *t; ///< %Town of the scope.
24 bool readonly; ///< When set, persistent storage of the town is read-only,
26 /**
27 * Resolver of a town scope.
28 * @param ro Surrounding resolver.
29 * @param t %Town of the scope.
30 * @param readonly Scope may change persistent storage of the town.
32 TownScopeResolver(ResolverObject &ro, Town *t, bool readonly)
33 : ScopeResolver(ro), t(t), readonly(readonly)
37 uint32_t GetVariable(uint8_t variable, [[maybe_unused]] uint32_t parameter, bool &available) const override;
38 void StorePSA(uint reg, int32_t value) override;
41 /** Resolver of town properties. */
42 struct TownResolverObject : public ResolverObject {
43 TownScopeResolver town_scope; ///< Scope resolver specific for towns.
45 TownResolverObject(const struct GRFFile *grffile, Town *t, bool readonly);
47 ScopeResolver *GetScope(VarSpriteGroupScope scope = VSG_SCOPE_SELF, uint8_t relative = 0) override
49 switch (scope) {
50 case VSG_SCOPE_SELF: return &town_scope;
51 default: return ResolverObject::GetScope(scope, relative);
56 #endif /* NEWGRF_TOWN_H */