src/logic_signals_cmd.cpp

   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 logic_signals_cmd.cpp Commands for modifying logic signal programs. */
   9
  10 #include "logic_signals.h"
  11 #include "core/bitmath_func.hpp"
  12 #include "window_func.h"
  13 #include "command_func.h"
  14 #include "rail_map.h"
  15 #include "table/strings.h"
  16 #include "company_func.h"
  17
  18 /**
  19  * The main command for editing a signal program.
  20  * @param tile The tile which contains the edited signal.
  21  * @param flags Internal command handler stuff.
  22  * @param p1 Bitstuffed items
  23  * - p1 = (bit 0-2) - The Track part of the signal program tile.
  24  * - p1 = (bit 3-5) - Subcommand to execute.
  25  * - p1 = (bit 6-7) - The value to set to the signal program.
  26  * @param p2 Target SignalReference for linking of two signals
  27  * @param text Unused
  28  * @return the cost of this operation (which is free), or an error
  29  */
  30 CommandCost CmdProgramLogicSignal(TileIndex tile, DoCommandFlag flags, uint32 p1, uint32 p2, const char* text)
  31 {
  32         const auto track = Extract<Track, 0, 3>(p1);
  33         const uint32 sub_cmd = GB(p1, 3, 3);
  34         const uint32 value = GB(p1, 6, 2);
  35
  36         // Start by checking tile ownership.
  37         CommandCost ret = CheckTileOwnership(tile);
  38         if (ret.Failed()) return ret;
  39
  40         SignalProgram* program = FindSignalProgram(tile, track);
  41
  42         if (sub_cmd == 1) {
  43                 if (flags & DC_EXEC) {
  44                         program->own_default_state = static_cast<SignalState>(value);
  45                 }
  46         } else if (sub_cmd == 2) {
  47                 if (flags & DC_EXEC) {
  48                         program->trigger_state = static_cast<SignalState>(value);
  49                 }
  50         } else if (sub_cmd == 3) {
  51                 if (flags & DC_EXEC) {
  52                         program->signal_op = static_cast<SignalOperator>(value);
  53                 }
  54         } else if (sub_cmd == 4) {
  55                 const TileIndex target_tile = p2;
  56                 const Track target_track = SignalTrackFromTile(target_tile);
  57
  58                 if (tile == target_tile && track == target_track) {
  59                         return CommandError(STR_ERROR_LINK_SIGNAL_TO_ITSELF);
  60                 }
  61
  62                 if (!IsPlainRailTile(target_tile) || !HasSignalOnTrack(target_tile, target_track)) {
  63                         return CommandError(STR_ERROR_LINK_SIGNAL_NO_SIGNAL);
  64                 }
  65
  66                 if (CheckTileOwnership(target_tile).Failed()) {
  67                         return CommandError(STR_ERROR_OWNED_BY);
  68                 }
  69
  70                 if (flags & DC_EXEC) {
  71                         program->AddLink(target_tile, target_track);
  72                 }
  73         } else if (sub_cmd == 5) {
  74                 if (flags & DC_EXEC) {
  75                         program->ClearAllLinks();
  76                 }
  77         }
  78
  79         if (flags & DC_EXEC) {
  80                 // Invalidate any open windows if something was changed.
  81                 InvalidateWindowData(WC_SIGNAL_PROGRAM, GetSignalReference(tile, track));
  82
  83                 // Re-evaluate the signal state too.
  84                 program->InputChanged(1);
  85         }
  86
  87         // No cost, this fun is free :)
  88         return CommandCost();
  89 }