# elrail.cpp

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    00001 /* $Id$ */
    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
    00057 #include "stdafx.h"
    00058 #include "station_map.h"
    00059 #include "viewport_func.h"
    00060 #include "train.h"
    00061 #include "rail_gui.h"
    00062 #include "tunnelbridge_map.h"
    00063 #include "tunnelbridge.h"
    00064 #include "elrail_func.h"
    00065 #include "company_base.h"
    00066 #include "newgrf_railtype.h"
    00067
    00068 #include "table/elrail_data.h"
    00069
    00075 static inline TLG GetTLG(TileIndex t)
    00076 {
    00077   return (TLG)((HasBit(TileX(t), 0) << 1) + HasBit(TileY(t), 0));
    00078 }
    00079
    00086 static TrackBits GetRailTrackBitsUniversal(TileIndex t, byte *override)
    00087 {
    00088   switch (GetTileType(t)) {
    00089     case MP_RAILWAY:
    00090       if (!HasCatenary(GetRailType(t))) return TRACK_BIT_NONE;
    00091       switch (GetRailTileType(t)) {
    00092         case RAIL_TILE_NORMAL: case RAIL_TILE_SIGNALS:
    00093           return GetTrackBits(t);
    00094         default:
    00095           return TRACK_BIT_NONE;
    00096       }
    00097       break;
    00098
    00099     case MP_TUNNELBRIDGE:
    00100       if (!HasCatenary(GetRailType(t))) return TRACK_BIT_NONE;
    00101       if (override != NULL && (IsTunnel(t) || GetTunnelBridgeLength(t, GetOtherBridgeEnd(t)) > 0)) {
    00102         *override = 1 << GetTunnelBridgeDirection(t);
    00103       }
    00104       return DiagDirToDiagTrackBits(GetTunnelBridgeDirection(t));
    00105
    00106     case MP_ROAD:
    00107       if (!IsLevelCrossing(t)) return TRACK_BIT_NONE;
    00108       if (!HasCatenary(GetRailType(t))) return TRACK_BIT_NONE;
    00109       return GetCrossingRailBits(t);
    00110
    00111     case MP_STATION:
    00112       if (!HasStationRail(t)) return TRACK_BIT_NONE;
    00113       if (!HasCatenary(GetRailType(t))) return TRACK_BIT_NONE;
    00114       if (!IsStationTileElectrifiable(t)) return TRACK_BIT_NONE;
    00115       return TrackToTrackBits(GetRailStationTrack(t));
    00116
    00117     default:
    00118       return TRACK_BIT_NONE;
    00119   }
    00120 }
    00121
    00125 static TrackBits MaskWireBits(TileIndex t, TrackBits tracks)
    00126 {
    00127   if (!IsPlainRailTile(t)) return tracks;
    00128
    00129   TrackdirBits neighbour_tdb = TRACKDIR_BIT_NONE;
    00130   for (DiagDirection d = DIAGDIR_BEGIN; d < DIAGDIR_END; d++) {
    00131     /* If the neighbor tile is either not electrified or has no tracks that can be reached
    00132      * from this tile, mark all trackdirs that can be reached from the neighbour tile
    00133      * as needing no catenary. */
    00134     RailType rt = GetTileRailType(TileAddByDiagDir(t, d));
    00135     if (rt == INVALID_RAILTYPE || !HasCatenary(rt) || (TrackStatusToTrackBits(GetTileTrackStatus(TileAddByDiagDir(t, d), TRANSPORT_RAIL, 0)) & DiagdirReachesTracks(d)) == TRACK_BIT_NONE) {
    00136       neighbour_tdb |= DiagdirReachesTrackdirs(ReverseDiagDir(d));
    00137     }
    00138   }
    00139
    00140   /* If the tracks from either a diagonal crossing or don't overlap, both
    00141    * trackdirs have to be marked to mask the corresponding track bit. Else
    00142    * one marked trackdir is enough the mask the track bit. */
    00143   TrackBits mask;
    00144   if (tracks == TRACK_BIT_CROSS || !TracksOverlap(tracks)) {
    00145     /* If the tracks form either a diagonal crossing or don't overlap, both
    00146      * trackdirs have to be marked to mask the corresponding track bit. */
    00147     mask = ~(TrackBits)((neighbour_tdb & (neighbour_tdb >> 8)) & TRACK_BIT_MASK);
    00148     /* If that results in no masked tracks and it is not a diagonal crossing,
    00149      * require only one marked trackdir to mask. */
    00150     if (tracks != TRACK_BIT_CROSS && (mask & TRACK_BIT_MASK) == TRACK_BIT_MASK) mask = ~TrackdirBitsToTrackBits(neighbour_tdb);
    00151   } else {
    00152     /* Require only one marked trackdir to mask the track. */
    00153     mask = ~TrackdirBitsToTrackBits(neighbour_tdb);
    00154     /* If that results in an empty set, require both trackdirs for diagonal track. */
    00155     if ((tracks & mask) == TRACK_BIT_NONE) {
    00156       if ((neighbour_tdb & TRACKDIR_BIT_X_NE) == 0 || (neighbour_tdb & TRACKDIR_BIT_X_SW) == 0) mask |= TRACK_BIT_X;
    00157       if ((neighbour_tdb & TRACKDIR_BIT_Y_NW) == 0 || (neighbour_tdb & TRACKDIR_BIT_Y_SE) == 0) mask |= TRACK_BIT_Y;
    00158       /* If that still is not enough, require both trackdirs for any track. */
    00159       if ((tracks & mask) == TRACK_BIT_NONE) mask = ~(TrackBits)((neighbour_tdb & (neighbour_tdb >> 8)) & TRACK_BIT_MASK);
    00160     }
    00161   }
    00162
    00163   /* Mask the tracks only if at least one track bit would remain. */
    00164   return (tracks & mask) != TRACK_BIT_NONE ? tracks & mask : tracks;
    00165 }
    00166
    00170 static inline SpriteID GetWireBase(TileIndex tile, TileContext context = TCX_NORMAL)
    00171 {
    00172   const RailtypeInfo *rti = GetRailTypeInfo(GetRailType(tile));
    00173   SpriteID wires = GetCustomRailSprite(rti, tile, RTSG_WIRES, context);
    00174   return wires == 0 ? SPR_WIRE_BASE : wires;
    00175 }
    00176
    00180 static inline SpriteID GetPylonBase(TileIndex tile, TileContext context = TCX_NORMAL)
    00181 {
    00182   const RailtypeInfo *rti = GetRailTypeInfo(GetRailType(tile));
    00183   SpriteID pylons = GetCustomRailSprite(rti, tile, RTSG_PYLONS, context);
    00184   return pylons == 0 ? SPR_PYLON_BASE : pylons;
    00185 }
    00186
    00192 static void AdjustTileh(TileIndex tile, Slope *tileh)
    00193 {
    00194   if (IsTileType(tile, MP_TUNNELBRIDGE)) {
    00195     if (IsTunnel(tile)) {
    00196       *tileh = SLOPE_STEEP; // XXX - Hack to make tunnel entrances to always have a pylon
    00197     } else if (*tileh != SLOPE_FLAT) {
    00198       *tileh = SLOPE_FLAT;
    00199     } else {
    00200       *tileh = InclinedSlope(GetTunnelBridgeDirection(tile));
    00201     }
    00202   }
    00203 }
    00204
    00212 static int32 GetPCPElevation(TileIndex tile, DiagDirection PCPpos)
    00213 {
    00214   /* The elevation of the "pylon"-sprite should be the elevation at the PCP.
    00215    * PCPs are always on a tile edge.
    00216    *
    00217    * This position can be outside of the tile, i.e. ?_pcp_offset == TILE_SIZE > TILE_SIZE - 1.
    00218    * So we have to move it inside the tile, because if the neighboured tile has a foundation,
    00219    * that does not smoothly connect to the current tile, we will get a wrong elevation from GetSlopeZ().
    00220    *
    00221    * When we move the position inside the tile, we will get a wrong elevation if we have a slope.
    00222    * To catch all cases we round the Z position to the next (TILE_HEIGHT / 2).
    00223    * This will return the correct elevation for slopes and will also detect non-continuous elevation on edges.
    00224    *
    00225    * Also note that the result of GetSlopeZ() is very special on bridge-ramps.
    00226    */
    00227
    00228   int32 z = GetSlopeZ(TileX(tile) * TILE_SIZE + min(x_pcp_offsets[PCPpos], TILE_SIZE - 1), TileY(tile) * TILE_SIZE + min(y_pcp_offsets[PCPpos], TILE_SIZE - 1));
    00229   z = (z + TILE_HEIGHT / 4) / (TILE_HEIGHT / 2) * (TILE_HEIGHT / 2);
    00230   return z;
    00231   /* Removed because this bit magic almost surely does no longer work with int32.
    00232    * return (z + 2) & ~3; // this means z = (z + TILE_HEIGHT / 4) / (TILE_HEIGHT / 2) * (TILE_HEIGHT / 2); */
    00233 }
    00234
    00242 void DrawCatenaryOnTunnel(const TileInfo *ti)
    00243 {
    00244   /* xmin, ymin, xmax + 1, ymax + 1 of BB */
    00245   static const int _tunnel_wire_BB[4][4] = {
    00246     { 0, 1, 16, 15 }, // NE
    00247     { 1, 0, 15, 16 }, // SE
    00248     { 0, 1, 16, 15 }, // SW
    00249     { 1, 0, 15, 16 }, // NW
    00250   };
    00251
    00252   DiagDirection dir = GetTunnelBridgeDirection(ti->tile);
    00253
    00254   SpriteID wire_base = GetWireBase(ti->tile);
    00255
    00256   const SortableSpriteStruct *sss = &CatenarySpriteData_Tunnel[dir];
    00257   const int *BB_data = _tunnel_wire_BB[dir];
    00258   AddSortableSpriteToDraw(
    00259     wire_base + sss->image_offset, PAL_NONE, ti->x + sss->x_offset, ti->y + sss->y_offset,
    00260     BB_data[2] - sss->x_offset, BB_data[3] - sss->y_offset, BB_Z_SEPARATOR - sss->z_offset + 1,
    00261     GetTileZ(ti->tile) + sss->z_offset,
    00262     IsTransparencySet(TO_CATENARY),
    00263     BB_data[0] - sss->x_offset, BB_data[1] - sss->y_offset, BB_Z_SEPARATOR - sss->z_offset
    00264   );
    00265 }
    00266
    00271 static void DrawCatenaryRailway(const TileInfo *ti)
    00272 {
    00273   /* Pylons are placed on a tile edge, so we need to take into account
    00274    * the track configuration of 2 adjacent tiles. trackconfig[0] stores the
    00275    * current tile (home tile) while [1] holds the neighbour */
    00276   TrackBits trackconfig[TS_END];
    00277   TrackBits wireconfig[TS_END];
    00278   bool isflat[TS_END];
    00279   /* Note that ti->tileh has already been adjusted for Foundations */
    00280   Slope tileh[TS_END] = { ti->tileh, SLOPE_FLAT };
    00281
    00282   /* Half tile slopes coincide only with horizontal/vertical track.
    00283    * Faking a flat slope results in the correct sprites on positions. */
    00284   Corner halftile_corner = CORNER_INVALID;
    00285   if (IsHalftileSlope(tileh[TS_HOME])) {
    00286     halftile_corner = GetHalftileSlopeCorner(tileh[TS_HOME]);
    00287     tileh[TS_HOME] = SLOPE_FLAT;
    00288   }
    00289
    00290   TLG tlg = GetTLG(ti->tile);
    00291   byte PCPstatus = 0;
    00292   byte OverridePCP = 0;
    00293   byte PPPpreferred[DIAGDIR_END];
    00294   byte PPPallowed[DIAGDIR_END];
    00295
    00296   /* Find which rail bits are present, and select the override points.
    00297    * We don't draw a pylon:
    00298    * 1) INSIDE a tunnel (we wouldn't see it anyway)
    00299    * 2) on the "far" end of a bridge head (the one that connects to bridge middle),
    00300    *    because that one is drawn on the bridge. Exception is for length 0 bridges
    00301    *    which have no middle tiles */
    00302   trackconfig[TS_HOME] = GetRailTrackBitsUniversal(ti->tile, &OverridePCP);
    00303   wireconfig[TS_HOME] = MaskWireBits(ti->tile, trackconfig[TS_HOME]);
    00304   /* If a track bit is present that is not in the main direction, the track is level */
    00305   isflat[TS_HOME] = ((trackconfig[TS_HOME] & (TRACK_BIT_HORZ | TRACK_BIT_VERT)) != 0);
    00306
    00307   AdjustTileh(ti->tile, &tileh[TS_HOME]);
    00308
    00309   SpriteID pylon_normal = GetPylonBase(ti->tile);
    00310   SpriteID pylon_halftile = (halftile_corner != CORNER_INVALID) ? GetPylonBase(ti->tile, TCX_UPPER_HALFTILE) : pylon_normal;
    00311
    00312   for (DiagDirection i = DIAGDIR_BEGIN; i < DIAGDIR_END; i++) {
    00313     static const uint edge_corners[] = {
    00314       1 << CORNER_N | 1 << CORNER_E, // DIAGDIR_NE
    00315       1 << CORNER_S | 1 << CORNER_E, // DIAGDIR_SE
    00316       1 << CORNER_S | 1 << CORNER_W, // DIAGDIR_SW
    00317       1 << CORNER_N | 1 << CORNER_W, // DIAGDIR_NW
    00318     };
    00319     SpriteID pylon_base = (halftile_corner != CORNER_INVALID && HasBit(edge_corners[i], halftile_corner)) ? pylon_halftile : pylon_normal;
    00320     TileIndex neighbour = ti->tile + TileOffsByDiagDir(i);
    00321     int32 elevation = GetPCPElevation(ti->tile, i);
    00322
    00323     /* Here's one of the main headaches. GetTileSlope does not correct for possibly
    00324      * existing foundataions, so we do have to do that manually later on.*/
    00325     tileh[TS_NEIGHBOUR] = GetTileSlope(neighbour, NULL);
    00326     trackconfig[TS_NEIGHBOUR] = GetRailTrackBitsUniversal(neighbour, NULL);
    00327     wireconfig[TS_NEIGHBOUR] = MaskWireBits(neighbour, trackconfig[TS_NEIGHBOUR]);
    00328     if (IsTunnelTile(neighbour) && i != GetTunnelBridgeDirection(neighbour)) wireconfig[TS_NEIGHBOUR] = trackconfig[TS_NEIGHBOUR] = TRACK_BIT_NONE;
    00329
    00330     /* If the neighboured tile does not smoothly connect to the current tile (because of a foundation),
    00331      * we have to draw all pillars on the current tile. */
    00332     if (elevation != GetPCPElevation(neighbour, ReverseDiagDir(i))) wireconfig[TS_NEIGHBOUR] = trackconfig[TS_NEIGHBOUR] = TRACK_BIT_NONE;
    00333
    00334     isflat[TS_NEIGHBOUR] = ((trackconfig[TS_NEIGHBOUR] & (TRACK_BIT_HORZ | TRACK_BIT_VERT)) != 0);
    00335
    00336     PPPpreferred[i] = 0xFF; // We start with preferring everything (end-of-line in any direction)
    00337     PPPallowed[i] = AllowedPPPonPCP[i];
    00338
    00339     /* We cycle through all the existing tracks at a PCP and see what
    00340      * PPPs we want to have, or may not have at all */
    00341     for (uint k = 0; k < NUM_TRACKS_AT_PCP; k++) {
    00342       /* Next to us, we have a bridge head, don't worry about that one, if it shows away from us */
    00343       if (TrackSourceTile[i][k] == TS_NEIGHBOUR &&
    00344           IsBridgeTile(neighbour) &&
    00345           GetTunnelBridgeDirection(neighbour) == ReverseDiagDir(i)) {
    00346         continue;
    00347       }
    00348
    00349       /* We check whether the track in question (k) is present in the tile
    00350        * (TrackSourceTile) */
    00351       DiagDirection PCPpos = i;
    00352       if (HasBit(wireconfig[TrackSourceTile[i][k]], TracksAtPCP[i][k])) {
    00353         /* track found, if track is in the neighbour tile, adjust the number
    00354          * of the PCP for preferred/allowed determination*/
    00355         PCPpos = (TrackSourceTile[i][k] == TS_HOME) ? i : ReverseDiagDir(i);
    00356         SetBit(PCPstatus, i); // This PCP is in use
    00357         PPPpreferred[i] &= PreferredPPPofTrackAtPCP[TracksAtPCP[i][k]][PCPpos];
    00358       }
    00359
    00360       if (HasBit(trackconfig[TrackSourceTile[i][k]], TracksAtPCP[i][k])) {
    00361         PPPallowed[i] &= ~DisallowedPPPofTrackAtPCP[TracksAtPCP[i][k]][PCPpos];
    00362       }
    00363     }
    00364
    00365     /* Deactivate all PPPs if PCP is not used */
    00366     if (!HasBit(PCPstatus, i)) {
    00367       PPPpreferred[i] = 0;
    00368       PPPallowed[i] = 0;
    00369     }
    00370
    00371     Foundation foundation = FOUNDATION_NONE;
    00372
    00373     /* Station and road crossings are always "flat", so adjust the tileh accordingly */
    00374     if (IsTileType(neighbour, MP_STATION) || IsTileType(neighbour, MP_ROAD)) tileh[TS_NEIGHBOUR] = SLOPE_FLAT;
    00375
    00376     /* Read the foundataions if they are present, and adjust the tileh */
    00377     if (trackconfig[TS_NEIGHBOUR] != TRACK_BIT_NONE && IsTileType(neighbour, MP_RAILWAY) && HasCatenary(GetRailType(neighbour))) foundation = GetRailFoundation(tileh[TS_NEIGHBOUR], trackconfig[TS_NEIGHBOUR]);
    00378     if (IsBridgeTile(neighbour)) {
    00379       foundation = GetBridgeFoundation(tileh[TS_NEIGHBOUR], DiagDirToAxis(GetTunnelBridgeDirection(neighbour)));
    00380     }
    00381
    00382     ApplyFoundationToSlope(foundation, &tileh[TS_NEIGHBOUR]);
    00383
    00384     /* Half tile slopes coincide only with horizontal/vertical track.
    00385      * Faking a flat slope results in the correct sprites on positions. */
    00386     if (IsHalftileSlope(tileh[TS_NEIGHBOUR])) tileh[TS_NEIGHBOUR] = SLOPE_FLAT;
    00387
    00388     AdjustTileh(neighbour, &tileh[TS_NEIGHBOUR]);
    00389
    00390     /* If we have a straight (and level) track, we want a pylon only every 2 tiles
    00391      * Delete the PCP if this is the case.
    00392      * Level means that the slope is the same, or the track is flat */
    00393     if (tileh[TS_HOME] == tileh[TS_NEIGHBOUR] || (isflat[TS_HOME] && isflat[TS_NEIGHBOUR])) {
    00394       for (uint k = 0; k < NUM_IGNORE_GROUPS; k++) {
    00395         if (PPPpreferred[i] == IgnoredPCP[k][tlg][i]) ClrBit(PCPstatus, i);
    00396       }
    00397     }
    00398
    00399     /* Now decide where we draw our pylons. First try the preferred PPPs, but they may not exist.
    00400      * In that case, we try the any of the allowed ones. if they don't exist either, don't draw
    00401      * anything. Note that the preferred PPPs still contain the end-of-line markers.
    00402      * Remove those (simply by ANDing with allowed, since these markers are never allowed) */
    00403     if ((PPPallowed[i] & PPPpreferred[i]) != 0) PPPallowed[i] &= PPPpreferred[i];
    00404
    00405     if (MayHaveBridgeAbove(ti->tile) && IsBridgeAbove(ti->tile)) {
    00406       Track bridgetrack = GetBridgeAxis(ti->tile) == AXIS_X ? TRACK_X : TRACK_Y;
    00407       uint height = GetBridgeHeight(GetNorthernBridgeEnd(ti->tile));
    00408
    00409       if ((height <= GetTileMaxZ(ti->tile) + TILE_HEIGHT) &&
    00410           (i == PCPpositions[bridgetrack][0] || i == PCPpositions[bridgetrack][1])) {
    00411         SetBit(OverridePCP, i);
    00412       }
    00413     }
    00414
    00415     if (PPPallowed[i] != 0 && HasBit(PCPstatus, i) && !HasBit(OverridePCP, i)) {
    00416       for (Direction k = DIR_BEGIN; k < DIR_END; k++) {
    00417         byte temp = PPPorder[i][GetTLG(ti->tile)][k];
    00418
    00419         if (HasBit(PPPallowed[i], temp)) {
    00420           uint x  = ti->x + x_pcp_offsets[i] + x_ppp_offsets[temp];
    00421           uint y  = ti->y + y_pcp_offsets[i] + y_ppp_offsets[temp];
    00422
    00423           /* Don't build the pylon if it would be outside the tile */
    00424           if (!HasBit(OwnedPPPonPCP[i], temp)) {
    00425             /* We have a neighour that will draw it, bail out */
    00426             if (trackconfig[TS_NEIGHBOUR] != TRACK_BIT_NONE) break;
    00427             continue; // No neighbour, go looking for a better position
    00428           }
    00429
    00430           AddSortableSpriteToDraw(pylon_base + pylon_sprites[temp], PAL_NONE, x, y, 1, 1, BB_HEIGHT_UNDER_BRIDGE,
    00431             elevation, IsTransparencySet(TO_CATENARY), -1, -1);
    00432
    00433           break; // We already have drawn a pylon, bail out
    00434         }
    00435       }
    00436     }
    00437   }
    00438
    00439   /* The wire above the tunnel is drawn together with the tunnel-roof (see DrawCatenaryOnTunnel()) */
    00440   if (IsTunnelTile(ti->tile)) return;
    00441
    00442   /* Don't draw a wire under a low bridge */
    00443   if (MayHaveBridgeAbove(ti->tile) && IsBridgeAbove(ti->tile) && !IsTransparencySet(TO_CATENARY)) {
    00444     uint height = GetBridgeHeight(GetNorthernBridgeEnd(ti->tile));
    00445
    00446     if (height <= GetTileMaxZ(ti->tile) + TILE_HEIGHT) return;
    00447   }
    00448
    00449   SpriteID wire_normal = GetWireBase(ti->tile);
    00450   SpriteID wire_halftile = (halftile_corner != CORNER_INVALID) ? GetWireBase(ti->tile, TCX_UPPER_HALFTILE) : wire_normal;
    00451   Track halftile_track;
    00452   switch (halftile_corner) {
    00453     case CORNER_W: halftile_track = TRACK_LEFT; break;
    00454     case CORNER_S: halftile_track = TRACK_LOWER; break;
    00455     case CORNER_E: halftile_track = TRACK_RIGHT; break;
    00456     case CORNER_N: halftile_track = TRACK_UPPER; break;
    00457     default:       halftile_track = INVALID_TRACK; break;
    00458   }
    00459
    00460   /* Drawing of pylons is finished, now draw the wires */
    00461   Track t;
    00462   FOR_EACH_SET_TRACK(t, wireconfig[TS_HOME]) {
    00463     SpriteID wire_base = (t == halftile_track) ? wire_halftile : wire_normal;
    00464     byte PCPconfig = HasBit(PCPstatus, PCPpositions[t][0]) +
    00465       (HasBit(PCPstatus, PCPpositions[t][1]) << 1);
    00466
    00467     const SortableSpriteStruct *sss;
    00468     int tileh_selector = !(tileh[TS_HOME] % 3) * tileh[TS_HOME] / 3; // tileh for the slopes, 0 otherwise
    00469
    00470     assert(PCPconfig != 0); // We have a pylon on neither end of the wire, that doesn't work (since we have no sprites for that)
    00471     assert(!IsSteepSlope(tileh[TS_HOME]));
    00472     sss = &CatenarySpriteData[Wires[tileh_selector][t][PCPconfig]];
    00473
    00474     /*
    00475      * The "wire"-sprite position is inside the tile, i.e. 0 <= sss->?_offset < TILE_SIZE.
    00476      * Therefore it is safe to use GetSlopeZ() for the elevation.
    00477      * Also note that the result of GetSlopeZ() is very special for bridge-ramps.
    00478      */
    00479     AddSortableSpriteToDraw(wire_base + sss->image_offset, PAL_NONE, ti->x + sss->x_offset, ti->y + sss->y_offset,
    00480       sss->x_size, sss->y_size, sss->z_size, GetSlopeZ(ti->x + sss->x_offset, ti->y + sss->y_offset) + sss->z_offset,
    00481       IsTransparencySet(TO_CATENARY));
    00482   }
    00483 }
    00484
    00492 void DrawCatenaryOnBridge(const TileInfo *ti)
    00493 {
    00494   TileIndex end = GetSouthernBridgeEnd(ti->tile);
    00495   TileIndex start = GetOtherBridgeEnd(end);
    00496
    00497   uint length = GetTunnelBridgeLength(start, end);
    00498   uint num = GetTunnelBridgeLength(ti->tile, start) + 1;
    00499   uint height;
    00500
    00501   const SortableSpriteStruct *sss;
    00502   Axis axis = GetBridgeAxis(ti->tile);
    00503   TLG tlg = GetTLG(ti->tile);
    00504
    00505   CatenarySprite offset = (CatenarySprite)(axis == AXIS_X ? 0 : WIRE_Y_FLAT_BOTH - WIRE_X_FLAT_BOTH);
    00506
    00507   if ((length % 2) && num == length) {
    00508     /* Draw the "short" wire on the southern end of the bridge
    00509      * only needed if the length of the bridge is odd */
    00510     sss = &CatenarySpriteData[WIRE_X_FLAT_BOTH + offset];
    00511   } else {
    00512     /* Draw "long" wires on all other tiles of the bridge (one pylon every two tiles) */
    00513     sss = &CatenarySpriteData[WIRE_X_FLAT_SW + (num % 2) + offset];
    00514   }
    00515
    00516   height = GetBridgeHeight(end);
    00517
    00518   SpriteID wire_base = GetWireBase(end, TCX_ON_BRIDGE);
    00519
    00520   AddSortableSpriteToDraw(wire_base + sss->image_offset, PAL_NONE, ti->x + sss->x_offset, ti->y + sss->y_offset,
    00521     sss->x_size, sss->y_size, sss->z_size, height + sss->z_offset,
    00522     IsTransparencySet(TO_CATENARY)
    00523   );
    00524
    00525   SpriteID pylon_base = GetPylonBase(end, TCX_ON_BRIDGE);
    00526
    00527   /* Finished with wires, draw pylons
    00528    * every other tile needs a pylon on the northern end */
    00529   if (num % 2) {
    00530     DiagDirection PCPpos = (axis == AXIS_X ? DIAGDIR_NE : DIAGDIR_NW);
    00531     Direction PPPpos = (axis == AXIS_X ? DIR_NW : DIR_NE);
    00532     if (HasBit(tlg, (axis == AXIS_X ? 0 : 1))) PPPpos = ReverseDir(PPPpos);
    00533     uint x = ti->x + x_pcp_offsets[PCPpos] + x_ppp_offsets[PPPpos];
    00534     uint y = ti->y + y_pcp_offsets[PCPpos] + y_ppp_offsets[PPPpos];
    00535     AddSortableSpriteToDraw(pylon_base + pylon_sprites[PPPpos], PAL_NONE, x, y, 1, 1, BB_HEIGHT_UNDER_BRIDGE, height, IsTransparencySet(TO_CATENARY), -1, -1);
    00536   }
    00537
    00538   /* need a pylon on the southern end of the bridge */
    00539   if (GetTunnelBridgeLength(ti->tile, start) + 1 == length) {
    00540     DiagDirection PCPpos = (axis == AXIS_X ? DIAGDIR_SW : DIAGDIR_SE);
    00541     Direction PPPpos = (axis == AXIS_X ? DIR_NW : DIR_NE);
    00542     if (HasBit(tlg, (axis == AXIS_X ? 0 : 1))) PPPpos = ReverseDir(PPPpos);
    00543     uint x = ti->x + x_pcp_offsets[PCPpos] + x_ppp_offsets[PPPpos];
    00544     uint y = ti->y + y_pcp_offsets[PCPpos] + y_ppp_offsets[PPPpos];
    00545     AddSortableSpriteToDraw(pylon_base + pylon_sprites[PPPpos], PAL_NONE, x, y, 1, 1, BB_HEIGHT_UNDER_BRIDGE, height, IsTransparencySet(TO_CATENARY), -1, -1);
    00546   }
    00547 }
    00548
    00554 void DrawCatenary(const TileInfo *ti)
    00555 {
    00556   switch (GetTileType(ti->tile)) {
    00557     case MP_RAILWAY:
    00558       if (IsRailDepot(ti->tile)) {
    00559         const SortableSpriteStruct *sss = &CatenarySpriteData_Depot[GetRailDepotDirection(ti->tile)];
    00560
    00561         SpriteID wire_base = GetWireBase(ti->tile);
    00562
    00563         /* This wire is not visible with the default depot sprites */
    00564         AddSortableSpriteToDraw(
    00565           wire_base + sss->image_offset, PAL_NONE, ti->x + sss->x_offset, ti->y + sss->y_offset,
    00566           sss->x_size, sss->y_size, sss->z_size,
    00567           GetTileMaxZ(ti->tile) + sss->z_offset,
    00568           IsTransparencySet(TO_CATENARY)
    00569         );
    00570         return;
    00571       }
    00572       break;
    00573
    00574     case MP_TUNNELBRIDGE:
    00575     case MP_ROAD:
    00576     case MP_STATION:
    00577       break;
    00578
    00579     default: return;
    00580   }
    00581   DrawCatenaryRailway(ti);
    00582 }
    00583
    00584 bool SettingsDisableElrail(int32 p1)
    00585 {
    00586   Company *c;
    00587   Train *t;
    00588   bool disable = (p1 != 0);
    00589
    00590   /* we will now walk through all electric train engines and change their railtypes if it is the wrong one*/
    00591   const RailType old_railtype = disable ? RAILTYPE_ELECTRIC : RAILTYPE_RAIL;
    00592   const RailType new_railtype = disable ? RAILTYPE_RAIL : RAILTYPE_ELECTRIC;
    00593
    00594   /* walk through all train engines */
    00595   Engine *e;
    00596   FOR_ALL_ENGINES_OF_TYPE(e, VEH_TRAIN) {
    00597     RailVehicleInfo *rv_info = &e->u.rail;
    00598     /* if it is an electric rail engine and its railtype is the wrong one */
    00599     if (rv_info->engclass == 2 && rv_info->railtype == old_railtype) {
    00600       /* change it to the proper one */
    00601       rv_info->railtype = new_railtype;
    00602     }
    00603   }
    00604
    00605   /* when disabling elrails, make sure that all existing trains can run on
    00606    *  normal rail too */
    00607   if (disable) {
    00608     FOR_ALL_TRAINS(t) {
    00609       if (t->railtype == RAILTYPE_ELECTRIC) {
    00610         /* this railroad vehicle is now compatible only with elrail,
    00611          *  so add there also normal rail compatibility */
    00612         t->compatible_railtypes |= RAILTYPES_RAIL;
    00613         t->railtype = RAILTYPE_RAIL;
    00614         SetBit(t->flags, VRF_EL_ENGINE_ALLOWED_NORMAL_RAIL);
    00615       }
    00616     }
    00617   }
    00618
    00619   /* Fix the total power and acceleration for trains */
    00620   FOR_ALL_TRAINS(t) {
    00621     /* power and acceleration is cached only for front engines */
    00622     if (t->IsFrontEngine()) {
    00623       t->ConsistChanged(true);
    00624     }
    00625   }
    00626
    00627   FOR_ALL_COMPANIES(c) c->avail_railtypes = GetCompanyRailtypes(c->index);
    00628
    00629   /* This resets the _last_built_railtype, which will be invalid for electric
    00630    * rails. It may have unintended consequences if that function is ever
    00631    * extended, though. */
    00632   ReinitGuiAfterToggleElrail(disable);
    00633   return true;
    00634 }