1

/* $Id$ */

     2

/** @file elrail.c

     3

 * This file deals with displaying wires and pylons for electric railways.

     4

 * <h2>Basics</h2>

     5

 *

     6

 * <h3>Tile Types</h3>

     7

 *

     8

 * We have two different types of tiles in the drawing code:

     9

 * Normal Railway Tiles (NRTs) which can have more than one track on it, and

    10

 * Special Railways tiles (SRTs) which have only one track (like crossings, depots

    11

 * stations, etc).

    12

 *

    13

 * <h3>Location Categories</h3>

    14

 *

    15

 * All tiles are categorized into three location groups (TLG):

    16

 * Group 0: Tiles with both an even X coordinate and an even Y coordinate

    17

 * Group 1: Tiles with an even X and an odd Y coordinate

    18

 * Group 2: Tiles with an odd X and an even Y coordinate

    19

 * Group 3: Tiles with both an odd X and Y coordnate.

    20

 *

    21

 * <h3>Pylon Points</h3>

    22

 * <h4>Control Points</h4>

    23

 * A Pylon Control Point (PCP) is a position where a wire (or rather two)

    24

 * is mounted onto a pylon.

    25

 * Each NRT does contain 4 PCPs which are bitmapped to a byte

    26

 * variable and are represented by the DiagDirection enum

    27

 *

    28

 * Each track ends on two PCPs and thus requires one pylon on each end. However,

    29

 * there is one exception: Straight-and-level tracks only have one pylon every

    30

 * other tile.

    31

 *

    32

 * Now on each edge there are two PCPs: One from each adjacent tile. Both PCPs

    33

 * are merged using an OR operation (i. e. if one tile needs a PCP at the postion

    34

 * in question, both tiles get it).

    35

 *

    36

 * <h4>Position Points</h4>

    37

 * A Pylon Position Point (PPP) is a position where a pylon is located on the

    38

 * ground.  Each PCP owns 8 in (45 degree steps) PPPs that are located around

    39

 * it. PPPs are represented using the Direction enum. Each track bit has PPPs

    40

 * that are impossible (because the pylon would be situated on the track) and

    41

 * some that are preferred (because the pylon would be rectangular to the track).

    42

 *

    43

 * <img src="../../elrail_tile.png">

    44

 * <img src="../../elrail_track.png">

    45

 *

    46

 */

    47

    48

#include "stdafx.h"

    49

#include "openttd.h"

    50

#include "station_map.h"

    51

#include "tile.h"

    52

#include "viewport.h"

    53

#include "functions.h" /* We should REALLY get rid of this goddamn file, as it is butt-ugly */

    54

#include "variables.h" /* ... same here */

    55

#include "rail.h"

    56

#include "debug.h"

    57

#include "tunnel_map.h"

    58

#include "road_map.h"

    59

#include "bridge_map.h"

    60

#include "bridge.h"

    61

#include "rail_map.h"

    62

#include "table/sprites.h"

    63

#include "table/elrail_data.h"

    64

#include "vehicle.h"

    65

#include "train.h"

    66

#include "gui.h"

    67

    68

static inline TLG GetTLG(TileIndex t)

    69

{

    70

	return (HASBIT(TileX(t), 0) << 1) + HASBIT(TileY(t), 0);

    71

}

    72

    73

/** Finds which Rail Bits are present on a given tile. For bridge tiles,

    74

 * returns track bits under the bridge

    75

 */

    76

static TrackBits GetRailTrackBitsUniversal(TileIndex t, byte *override)

    77

{

    78

	switch (GetTileType(t)) {

    79

		case MP_RAILWAY:

    80

			if (GetRailType(t) != RAILTYPE_ELECTRIC) return 0;

    81

			switch (GetRailTileType(t)) {

    82

				case RAIL_TILE_NORMAL: case RAIL_TILE_SIGNALS:

    83

					return GetTrackBits(t);

    84

				case RAIL_TILE_DEPOT_WAYPOINT:

    85

					if (GetRailTileSubtype(t) == RAIL_SUBTYPE_WAYPOINT) return GetRailWaypointBits(t);

    86

				default:

    87

					return 0;

    88

			}

    89

			break;

    90

    91

		case MP_TUNNELBRIDGE:

    92

			if (IsTunnel(t)) {

    93

				if (GetRailType(t) != RAILTYPE_ELECTRIC) return 0;

    94

				if (override != NULL) *override = 1 << GetTunnelDirection(t);

    95

				return AxisToTrackBits(DiagDirToAxis(GetTunnelDirection(t)));

    96

			} else {

    97

				if (GetRailType(t) != RAILTYPE_ELECTRIC) return 0;

    98

				if (IsBridgeMiddle(t)) {

    99

					if (IsTransportUnderBridge(t) &&

   100

						GetTransportTypeUnderBridge(t) == TRANSPORT_RAIL) {

   101

						return GetRailBitsUnderBridge(t);

   102

					} else {

   103

						return 0;

   104

					}

   105

				} else {

   106

					if (override != NULL && DistanceMax(t, GetOtherBridgeEnd(t)) > 1) *override = 1 << GetBridgeRampDirection(t);

   107

   108

					return AxisToTrackBits(DiagDirToAxis(GetBridgeRampDirection(t)));

   109

				}

   110

			}

   111

   112

		case MP_STREET:

   113

			if (GetRoadTileType(t) != ROAD_TILE_CROSSING) return 0;

   114

			if (GetRailTypeCrossing(t) != RAILTYPE_ELECTRIC) return 0;

   115

			return GetCrossingRailBits(t);

   116

   117

		case MP_STATION:

   118

			if (!IsRailwayStation(t)) return 0;

   119

			if (GetRailType(t) != RAILTYPE_ELECTRIC) return 0;

   120

			if (!IsStationTileElectrifiable(t)) return 0;

   121

			return TrackToTrackBits(GetRailStationTrack(t));

   122

   123

		default:

   124

			return 0;

   125

	}

   126

}

   127

   128

/** Corrects the tileh for certain tile types. Returns an effective tileh for the track on the tile.

   129

 * @param tile The tile to analyse

   130

 * @param *tileh the tileh

   131

 */

   132

static void AdjustTileh(TileIndex tile, Slope *tileh)

   133

{

   134

	if (IsTileType(tile, MP_TUNNELBRIDGE)) {

   135

		if (IsTunnel(tile)) {

   136

			*tileh = SLOPE_FLAT;

   137

		} else {

   138

			if (IsBridgeRamp(tile)) {

   139

				if (*tileh != SLOPE_FLAT) {

   140

					*tileh = SLOPE_FLAT;

   141

				} else {

   142

					switch (GetBridgeRampDirection(tile)) {

   143

						case DIAGDIR_NE: *tileh = SLOPE_NE; break;

   144

						case DIAGDIR_SE: *tileh = SLOPE_SE; break;

   145

						case DIAGDIR_SW: *tileh = SLOPE_SW; break;

   146

						case DIAGDIR_NW: *tileh = SLOPE_NW; break;

   147

						default: break;

   148

					}

   149

				}

   150

			}

   151

		}

   152

	}

   153

}

   154

   155

/** Draws wires and, if required, pylons on a given tile

   156

 * @param ti The Tileinfo to draw the tile for

   157

 */

   158

static void DrawCatenaryRailway(const TileInfo *ti)

   159

{

   160

	/* Pylons are placed on a tile edge, so we need to take into account

   161

	 * the track configuration of 2 adjacent tiles. trackconfig[0] stores the

   162

	 * current tile (home tile) while [1] holds the neighbour */

   163

	TrackBits trackconfig[TS_END];

   164

	bool isflat[TS_END];

   165

	/* Note that ti->tileh has already been adjusted for Foundations */

   166

	Slope tileh[TS_END] = { ti->tileh, SLOPE_FLAT };

   167

   168

	TLG tlg = GetTLG(ti->tile);

   169

	byte PCPstatus = 0;

   170

	byte OverridePCP = 0;

   171

	byte PPPpreferred[DIAGDIR_END];

   172

	byte PPPallowed[DIAGDIR_END];

   173

	DiagDirection i;

   174

	Track t;

   175

   176

	/* Find which rail bits are present, and select the override points.

   177

	 * We don't draw a pylon:

   178

	 * 1) INSIDE a tunnel (we wouldn't see it anyway)

   179

	 * 2) on the "far" end of a bridge head (the one that connects to bridge middle),

   180

	 *    because that one is drawn on the bridge. Exception is for length 0 bridges

   181

	 *    which have no middle tiles */

   182

	trackconfig[TS_HOME] = GetRailTrackBitsUniversal(ti->tile, &OverridePCP);

   183

	/* If a track bit is present that is not in the main direction, the track is level */

   184

	isflat[TS_HOME] = trackconfig[TS_HOME] & (TRACK_BIT_HORZ | TRACK_BIT_VERT);

   185

   186

	AdjustTileh(ti->tile, &tileh[TS_HOME]);

   187

   188

	for (i = DIAGDIR_NE; i < DIAGDIR_END; i++) {

   189

		TileIndex neighbour = ti->tile + TileOffsByDiagDir(i);

   190

		uint foundation = 0;

   191

		int k;

   192

   193

		/* Here's one of the main headaches. GetTileSlope does not correct for possibly

   194

		 * existing foundataions, so we do have to do that manually later on.*/

   195

		tileh[TS_NEIGHBOUR] = GetTileSlope(neighbour, NULL);

   196

		trackconfig[TS_NEIGHBOUR] = GetRailTrackBitsUniversal(neighbour, NULL);

   197

		if (IsTunnelTile(neighbour) && i != GetTunnelDirection(neighbour)) trackconfig[TS_NEIGHBOUR] = 0;

   198

		isflat[TS_NEIGHBOUR] = trackconfig[TS_NEIGHBOUR] & (TRACK_BIT_HORZ | TRACK_BIT_VERT);

   199

   200

		PPPpreferred[i] = 0xFF; /* We start with preferring everything (end-of-line in any direction) */

   201

		PPPallowed[i] = AllowedPPPonPCP[i];

   202

   203

		/* We cycle through all the existing tracks at a PCP and see what

   204

		 * PPPs we want to have, or may not have at all */

   205

		for (k = 0; k < NUM_TRACKS_AT_PCP; k++) {

   206

			/* Next to us, we have a bridge head, don't worry about that one, if it shows away from us */

   207

			if (TrackSourceTile[i][k] == TS_NEIGHBOUR &&

   208

			    IsBridgeTile(neighbour) && IsBridgeRamp(neighbour) &&

   209

			    GetBridgeRampDirection(neighbour) == ReverseDiagDir(i)) {

   210

				continue;

   211

			}

   212

   213

			/* We check whether the track in question (k) is present in the tile

   214

			 * (TrackSourceTile) */

   215

			if (HASBIT(trackconfig[TrackSourceTile[i][k]], TracksAtPCP[i][k])) {

   216

				/* track found, if track is in the neighbour tile, adjust the number

   217

				 * of the PCP for preferred/allowed determination*/

   218

				DiagDirection PCPpos = (TrackSourceTile[i][k] == TS_HOME) ? i : ReverseDiagDir(i);

   219

				SETBIT(PCPstatus, i); /* This PCP is in use */

   220

   221

				PPPpreferred[i] &= PreferredPPPofTrackAtPCP[TracksAtPCP[i][k]][PCPpos];

   222

				PPPallowed[i] &= ~DisallowedPPPofTrackAtPCP[TracksAtPCP[i][k]][PCPpos];

   223

			}

   224

		}

   225

   226

		/* Deactivate all PPPs if PCP is not used */

   227

		PPPpreferred[i] *= HASBIT(PCPstatus, i);

   228

		PPPallowed[i] *= HASBIT(PCPstatus, i);

   229

   230

		/* A station is always "flat", so adjust the tileh accordingly */

   231

		if (IsTileType(neighbour, MP_STATION)) tileh[TS_NEIGHBOUR] = SLOPE_FLAT;

   232

   233

		/* Read the foundataions if they are present, and adjust the tileh */

   234

		if (IsTileType(neighbour, MP_RAILWAY) && GetRailType(neighbour) == RAILTYPE_ELECTRIC) foundation = GetRailFoundation(tileh[TS_NEIGHBOUR], trackconfig[TS_NEIGHBOUR]);

   235

		if (IsBridgeTile(neighbour) && IsBridgeRamp(neighbour)) {

   236

			foundation = GetBridgeFoundation(tileh[TS_NEIGHBOUR], DiagDirToAxis(GetBridgeRampDirection(neighbour)));

   237

		}

   238

   239

		if (foundation != 0) {

   240

			if (foundation < 15) {

   241

				tileh[TS_NEIGHBOUR] = SLOPE_FLAT;

   242

			} else {

   243

				tileh[TS_NEIGHBOUR] = _inclined_tileh[foundation - 15];

   244

			}

   245

		}

   246

   247

		AdjustTileh(neighbour, &tileh[TS_NEIGHBOUR]);

   248

   249

		/* If we have a straight (and level) track, we want a pylon only every 2 tiles

   250

		 * Delete the PCP if this is the case. */

   251

		/* Level means that the slope is the same, or the track is flat */

   252

		if (tileh[TS_HOME] == tileh[TS_NEIGHBOUR] || (isflat[TS_HOME] && isflat[TS_NEIGHBOUR])) {

   253

			for (k = 0; k < NUM_IGNORE_GROUPS; k++)

   254

				if (PPPpreferred[i] == IgnoredPCP[k][tlg][i]) CLRBIT(PCPstatus, i);

   255

		}

   256

   257

		/* Now decide where we draw our pylons. First try the preferred PPPs, but they may not exist.

   258

		 * In that case, we try the any of the allowed ones. if they don't exist either, don't draw

   259

		 * anything. Note that the preferred PPPs still contain the end-of-line markers.

   260

		 * Remove those (simply by ANDing with allowed, since these markers are never allowed) */

   261

		if ((PPPallowed[i] & PPPpreferred[i]) != 0) PPPallowed[i] &= PPPpreferred[i];

   262

   263

		if (PPPallowed[i] != 0 && HASBIT(PCPstatus, i) && !HASBIT(OverridePCP, i)) {

   264

			for (k = 0; k < DIR_END; k++) {

   265

				byte temp = PPPorder[i][GetTLG(ti->tile)][k];

   266

   267

				if (HASBIT(PPPallowed[i], temp)) {

   268

					uint x  = ti->x + x_pcp_offsets[i] + x_ppp_offsets[temp];

   269

					uint y  = ti->y + y_pcp_offsets[i] + y_ppp_offsets[temp];

   270

   271

					/* Don't build the pylon if it would be outside the tile */

   272

					if (!HASBIT(OwnedPPPonPCP[i], temp)) {

   273

						/* We have a neighour that will draw it, bail out */

   274

						if (trackconfig[TS_NEIGHBOUR] != 0) break;

   275

						continue; /* No neighbour, go looking for a better position */

   276

					}

   277

   278

					AddSortableSpriteToDraw(pylons_normal[temp], x, y, 1, 1, 10,

   279

							GetSlopeZ(ti->x + x_pcp_offsets[i], ti->y + y_pcp_offsets[i]));

   280

					break; /* We already have drawn a pylon, bail out */

   281

				}

   282

			}

   283

		}

   284

	}

   285

   286

	/* Don't draw a wire under a low bridge */

   287

	if (IsBridgeTile(ti->tile) &&

   288

			IsBridgeMiddle(ti->tile) &&

   289

			!(_display_opt & DO_TRANS_BUILDINGS) &&

   290

			GetBridgeHeight(ti->tile) <= TilePixelHeight(ti->tile) + TILE_HEIGHT) {

   291

		return;

   292

	}

   293

   294

	/* Drawing of pylons is finished, now draw the wires */

   295

	for (t = 0; t < TRACK_END; t++) {

   296

		if (HASBIT(trackconfig[TS_HOME], t)) {

   297

   298

			byte PCPconfig = HASBIT(PCPstatus, PCPpositions[t][0]) +

   299

				(HASBIT(PCPstatus, PCPpositions[t][1]) << 1);

   300

   301

			const SortableSpriteStruct *sss;

   302

			int tileh_selector = !(tileh[TS_HOME] % 3) * tileh[TS_HOME] / 3; /* tileh for the slopes, 0 otherwise */

   303

   304

			assert(PCPconfig != 0); /* We have a pylon on neither end of the wire, that doesn't work (since we have no sprites for that) */

   305

			assert(!IsSteepSlope(tileh[TS_HOME]));

   306

			sss = &CatenarySpriteData[Wires[tileh_selector][t][PCPconfig]];

   307

   308

			AddSortableSpriteToDraw( sss->image, ti->x + sss->x_offset, ti->y + sss->y_offset,

   309

				sss->x_size, sss->y_size, sss->z_size, GetSlopeZ(ti->x + min(sss->x_offset, TILE_SIZE - 1), ti->y + min(sss->y_offset, TILE_SIZE - 1)) + sss->z_offset);

   310

		}

   311

	}

   312

}

   313

   314

static void DrawCatenaryOnBridge(const TileInfo *ti)

   315

{

   316

	TileIndex end = GetSouthernBridgeEnd(ti->tile);

   317

	TileIndex start = GetOtherBridgeEnd(end);

   318

   319

	uint length = GetBridgeLength(start, end);

   320

	uint num = DistanceMax(ti->tile, start);

   321

	uint height;

   322

   323

	const SortableSpriteStruct *sss;

   324

	Axis axis = GetBridgeAxis(ti->tile);

   325

	TLG tlg = GetTLG(ti->tile);

   326

   327

	CatenarySprite offset = axis == AXIS_X ? 0 : WIRE_Y_FLAT_BOTH - WIRE_X_FLAT_BOTH;

   328

   329

	if ((length % 2) && num == length) {

   330

		/* Draw the "short" wire on the southern end of the bridge

   331

		 * only needed if the length of the bridge is odd */

   332

		sss = &CatenarySpriteData[WIRE_X_FLAT_BOTH + offset];

   333

	} else {

   334

		/* Draw "long" wires on all other tiles of the bridge (one pylon every two tiles) */

   335

		sss = &CatenarySpriteData[WIRE_X_FLAT_SW + (num % 2) + offset];

   336

	}

   337

   338

	height = GetBridgeHeight(ti->tile);

   339

   340

	AddSortableSpriteToDraw( sss->image, ti->x + sss->x_offset, ti->y + sss->y_offset,

   341

		sss->x_size, sss->y_size, sss->z_size, height + sss->z_offset

   342

	);

   343

   344

	/* Finished with wires, draw pylons */

   345

	/* every other tile needs a pylon on the northern end */

   346

	if (num % 2) {

   347

		if (axis == AXIS_X) {

   348

			AddSortableSpriteToDraw(pylons_bridge[0 + HASBIT(tlg, 0)], ti->x, ti->y + 4 + 8 * HASBIT(tlg, 0), 1, 1, 10, height);

   349

		} else {

   350

			AddSortableSpriteToDraw(pylons_bridge[2 + HASBIT(tlg, 1)], ti->x + 4 + 8 * HASBIT(tlg, 1), ti->y, 1, 1, 10, height);

   351

		}

   352

	}

   353

   354

	/* need a pylon on the southern end of the bridge */

   355

	if (DistanceMax(ti->tile, start) == length) {

   356

		if (axis == AXIS_X) {

   357

			AddSortableSpriteToDraw(pylons_bridge[0 + HASBIT(tlg, 0)], ti->x + 16, ti->y + 4 + 8 * HASBIT(tlg, 0), 1, 1, 10, height);

   358

		} else {

   359

			AddSortableSpriteToDraw(pylons_bridge[2 + HASBIT(tlg, 1)], ti->x + 4 + 8 * HASBIT(tlg, 1), ti->y + 16, 1, 1, 10, height);

   360

		}

   361

	}

   362

}

   363

   364

void DrawCatenary(const TileInfo *ti)

   365

{

   366

	if (_patches.disable_elrails) return;

   367

   368

	switch (GetTileType(ti->tile)) {

   369

		case MP_RAILWAY:

   370

			if (IsRailDepot(ti->tile)) {

   371

				const SortableSpriteStruct* sss = &CatenarySpriteData_Depot[GetRailDepotDirection(ti->tile)];

   372

   373

				AddSortableSpriteToDraw(

   374

					sss->image, ti->x + sss->x_offset, ti->y + sss->y_offset,

   375

					sss->x_size, sss->y_size, sss->z_size,

   376

					GetTileMaxZ(ti->tile) + sss->z_offset

   377

				);

   378

				return;

   379

			}

   380

			break;

   381

   382

		case MP_TUNNELBRIDGE:

   383

			if (IsBridge(ti->tile) && IsBridgeMiddle(ti->tile) && GetRailTypeOnBridge(ti->tile) == RAILTYPE_ELECTRIC) DrawCatenaryOnBridge(ti);

   384

			break;

   385

   386

		case MP_STREET:  break;

   387

		case MP_STATION: break;

   388

   389

		default: return;

   390

	}

   391

	DrawCatenaryRailway(ti);

   392

}

   393

   394

int32 SettingsDisableElrail(int32 p1)

   395

{

   396

	EngineID e_id;

   397

	Vehicle* v;

   398

	Player *p;

   399

	bool disable = (p1 != 0);

   400

   401

	/* we will now walk through all electric train engines and change their railtypes if it is the wrong one*/

   402

	const RailType old_railtype = disable ? RAILTYPE_ELECTRIC : RAILTYPE_RAIL;

   403

	const RailType new_railtype = disable ? RAILTYPE_RAIL : RAILTYPE_ELECTRIC;

   404

   405

	/* walk through all train engines */

   406

	for (e_id = 0; e_id < NUM_TRAIN_ENGINES; e_id++)

   407

	{

   408

		const RailVehicleInfo *rv_info = RailVehInfo(e_id);

   409

		Engine *e = GetEngine(e_id);

   410

		/* if it is an electric rail engine and its railtype is the wrong one */

   411

		if (rv_info->engclass == 2 && e->railtype == old_railtype) {

   412

			/* change it to the proper one */

   413

			e->railtype = new_railtype;

   414

		}

   415

	}

   416

   417

	/* when disabling elrails, make sure that all existing trains can run on

   418

	*  normal rail too */

   419

	if (disable) {

   420

		FOR_ALL_VEHICLES(v) {

   421

			if (v->type == VEH_Train && v->u.rail.railtype == RAILTYPE_ELECTRIC) {

   422

				/* this railroad vehicle is now compatible only with elrail,

   423

				*  so add there also normal rail compatibility */

   424

				v->u.rail.compatible_railtypes |= (1 << RAILTYPE_RAIL);

   425

				v->u.rail.railtype = RAILTYPE_RAIL;

   426

				SETBIT(v->u.rail.flags, VRF_EL_ENGINE_ALLOWED_NORMAL_RAIL);

   427

			}

   428

		}

   429

	}

   430

   431

	/* setup total power for trains */

   432

	FOR_ALL_VEHICLES(v) {

   433

		/* power is cached only for front engines */

   434

		if (v->type == VEH_Train && IsFrontEngine(v)) TrainPowerChanged(v);

   435

	}

   436

   437

	FOR_ALL_PLAYERS(p) p->avail_railtypes = GetPlayerRailtypes(p->index);

   438

   439

	/* This resets the _last_built_railtype, which will be invalid for electric

   440

	* rails. It may have unintended consequences if that function is ever

   441

	* extended, though. */

   442

	ReinitGuiAfterToggleElrail(disable);

   443

	return 0;

   444

}