1

/* $Id$ */

     2

/** @file elrail.cpp

     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 (TLG)((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 TRACK_BIT_NONE;

    81

			switch (GetRailTileType(t)) {

    82

				case RAIL_TILE_NORMAL: case RAIL_TILE_SIGNALS:

    83

					return GetTrackBits(t);

    84

				case RAIL_TILE_WAYPOINT:

    85

					return GetRailWaypointBits(t);

    86

				default:

    87

					return TRACK_BIT_NONE;

    88

			}

    89

			break;

    90

    91

		case MP_TUNNELBRIDGE:

    92

			if (IsTunnel(t)) {

    93

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

    94

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

    95

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

    96

			} else {

    97

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

    98

				if (override != NULL && DistanceMax(t, GetOtherBridgeEnd(t)) > 1) {

    99

					*override = 1 << GetBridgeRampDirection(t);

   100

				}

   101

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

   102

			}

   103

   104

		case MP_STREET:

   105

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

   106

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

   107

			return GetCrossingRailBits(t);

   108

   109

		case MP_STATION:

   110

			if (!IsRailwayStation(t)) return TRACK_BIT_NONE;

   111

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

   112

			if (!IsStationTileElectrifiable(t)) return TRACK_BIT_NONE;

   113

			return TrackToTrackBits(GetRailStationTrack(t));

   114

   115

		default:

   116

			return TRACK_BIT_NONE;

   117

	}

   118

}

   119

   120

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

   121

 * @param tile The tile to analyse

   122

 * @param *tileh the tileh

   123

 */

   124

static void AdjustTileh(TileIndex tile, Slope *tileh)

   125

{

   126

	if (IsTileType(tile, MP_TUNNELBRIDGE)) {

   127

		if (IsTunnel(tile)) {

   128

			*tileh = SLOPE_STEEP; // XXX - Hack to make tunnel entrances to always have a pylon

   129

		} else if (*tileh != SLOPE_FLAT) {

   130

			*tileh = SLOPE_FLAT;

   131

		} else {

   132

			switch (GetBridgeRampDirection(tile)) {

   133

				case DIAGDIR_NE: *tileh = SLOPE_NE; break;

   134

				case DIAGDIR_SE: *tileh = SLOPE_SE; break;

   135

				case DIAGDIR_SW: *tileh = SLOPE_SW; break;

   136

				case DIAGDIR_NW: *tileh = SLOPE_NW; break;

   137

				default: NOT_REACHED();

   138

			}

   139

		}

   140

	}

   141

}

   142

   143

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

   144

 * @param ti The Tileinfo to draw the tile for

   145

 */

   146

static void DrawCatenaryRailway(const TileInfo *ti)

   147

{

   148

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

   149

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

   150

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

   151

	TrackBits trackconfig[TS_END];

   152

	bool isflat[TS_END];

   153

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

   154

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

   155

   156

	TLG tlg = GetTLG(ti->tile);

   157

	byte PCPstatus = 0;

   158

	byte OverridePCP = 0;

   159

	byte PPPpreferred[DIAGDIR_END];

   160

	byte PPPallowed[DIAGDIR_END];

   161

	DiagDirection i;

   162

	Track t;

   163

   164

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

   165

	 * We don't draw a pylon:

   166

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

   167

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

   168

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

   169

	 *    which have no middle tiles */

   170

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

   171

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

   172

	isflat[TS_HOME] = ((trackconfig[TS_HOME] & (TRACK_BIT_HORZ | TRACK_BIT_VERT)) != 0);

   173

   174

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

   175

   176

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

   177

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

   178

		uint foundation = 0;

   179

		int k;

   180

   181

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

   182

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

   183

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

   184

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

   185

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

   186

		isflat[TS_NEIGHBOUR] = ((trackconfig[TS_NEIGHBOUR] & (TRACK_BIT_HORZ | TRACK_BIT_VERT)) != 0);

   187

   188

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

   189

		PPPallowed[i] = AllowedPPPonPCP[i];

   190

   191

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

   192

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

   193

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

   194

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

   195

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

   196

			    IsBridgeTile(neighbour) &&

   197

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

   198

				continue;

   199

			}

   200

   201

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

   202

			 * (TrackSourceTile) */

   203

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

   204

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

   205

				 * of the PCP for preferred/allowed determination*/

   206

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

   207

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

   208

   209

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

   210

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

   211

			}

   212

		}

   213

   214

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

   215

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

   216

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

   217

   218

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

   219

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

   220

   221

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

   222

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

   223

		if (IsBridgeTile(neighbour)) {

   224

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

   225

		}

   226

   227

		if (foundation != 0) {

   228

			tileh[TS_NEIGHBOUR] = foundation < 15 ? SLOPE_FLAT : _inclined_tileh[foundation - 15];

   229

		}

   230

   231

		AdjustTileh(neighbour, &tileh[TS_NEIGHBOUR]);

   232

   233

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

   234

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

   235

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

   236

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

   237

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

   238

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

   239

		}

   240

   241

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

   242

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

   243

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

   244

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

   245

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

   246

   247

		if (MayHaveBridgeAbove(ti->tile) && IsBridgeAbove(ti->tile)) {

   248

			Track bridgetrack = GetBridgeAxis(ti->tile) == AXIS_X ? TRACK_X : TRACK_Y;

   249

			uint height = GetBridgeHeight(GetNorthernBridgeEnd(ti->tile));

   250

   251

			if ((height <= TilePixelHeight(ti->tile) + TILE_HEIGHT) &&

   252

					(i == PCPpositions[bridgetrack][0] || i == PCPpositions[bridgetrack][1])) {

   253

				SETBIT(OverridePCP, i);

   254

			}

   255

		}

   256

   257

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

   258

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

   259

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

   260

   261

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

   262

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

   263

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

   264

   265

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

   266

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

   267

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

   268

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

   269

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

   270

					}

   271

   272

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

   273

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

   274

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

   275

				}

   276

			}

   277

		}

   278

	}

   279

   280

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

   281

	if (MayHaveBridgeAbove(ti->tile) && IsBridgeAbove(ti->tile) && !(_display_opt & DO_TRANS_BUILDINGS)) {

   282

		uint height = GetBridgeHeight(GetNorthernBridgeEnd(ti->tile));

   283

   284

		if (height <= TilePixelHeight(ti->tile) + TILE_HEIGHT) return;

   285

	}

   286

   287

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

   288

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

   289

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

   290

			if (IsTunnelTile(ti->tile)) {

   291

				const SortableSpriteStruct *sss = &CatenarySpriteData_Tunnel[GetTunnelDirection(ti->tile)];

   292

   293

				AddSortableSpriteToDraw(

   294

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

   295

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

   296

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

   297

				);

   298

				break;

   299

			}

   300

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

   301

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

   302

   303

			const SortableSpriteStruct *sss;

   304

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

   305

   306

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

   307

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

   308

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

   309

   310

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

   311

				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);

   312

		}

   313

	}

   314

}

   315

   316

static void DrawCatenaryOnBridge(const TileInfo *ti)

   317

{

   318

	TileIndex end = GetSouthernBridgeEnd(ti->tile);

   319

	TileIndex start = GetOtherBridgeEnd(end);

   320

   321

	uint length = GetBridgeLength(start, end);

   322

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

   323

	uint height;

   324

   325

	const SortableSpriteStruct *sss;

   326

	Axis axis = GetBridgeAxis(ti->tile);

   327

	TLG tlg = GetTLG(ti->tile);

   328

   329

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

   330

   331

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

   332

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

   333

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

   334

		sss = &CatenarySpriteData[WIRE_X_FLAT_BOTH + offset];

   335

	} else {

   336

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

   337

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

   338

	}

   339

   340

	height = GetBridgeHeight(end);

   341

   342

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

   343

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

   344

	);

   345

   346

	/* Finished with wires, draw pylons */

   347

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

   348

	if (num % 2) {

   349

		if (axis == AXIS_X) {

   350

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

   351

		} else {

   352

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

   353

		}

   354

	}

   355

   356

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

   357

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

   358

		if (axis == AXIS_X) {

   359

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

   360

		} else {

   361

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

   362

		}

   363

	}

   364

}

   365

   366

void DrawCatenary(const TileInfo *ti)

   367

{

   368

	if (MayHaveBridgeAbove(ti->tile) && IsBridgeAbove(ti->tile)) {

   369

		TileIndex head = GetNorthernBridgeEnd(ti->tile);

   370

   371

		if (GetBridgeTransportType(head) == TRANSPORT_RAIL && GetRailType(head) == RAILTYPE_ELECTRIC) {

   372

			DrawCatenaryOnBridge(ti);

   373

		}

   374

	}

   375

	if (_patches.disable_elrails) return;

   376

   377

	switch (GetTileType(ti->tile)) {

   378

		case MP_RAILWAY:

   379

			if (IsRailDepot(ti->tile)) {

   380

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

   381

   382

				AddSortableSpriteToDraw(

   383

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

   384

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

   385

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

   386

				);

   387

				return;

   388

			}

   389

			break;

   390

   391

		case MP_TUNNELBRIDGE:

   392

		case MP_STREET:

   393

		case MP_STATION:

   394

			break;

   395

   396

		default: return;

   397

	}

   398

	DrawCatenaryRailway(ti);

   399

}

   400

   401

int32 SettingsDisableElrail(int32 p1)

   402

{

   403

	EngineID e_id;

   404

	Vehicle *v;

   405

	Player *p;

   406

	bool disable = (p1 != 0);

   407

   408

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

   409

	const RailType old_railtype = disable ? RAILTYPE_ELECTRIC : RAILTYPE_RAIL;

   410

	const RailType new_railtype = disable ? RAILTYPE_RAIL : RAILTYPE_ELECTRIC;

   411

   412

	/* walk through all train engines */

   413

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

   414

		RailVehicleInfo *rv_info = &_rail_vehicle_info[e_id];

   415

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

   416

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

   417

			/* change it to the proper one */

   418

			rv_info->railtype = new_railtype;

   419

		}

   420

	}

   421

   422

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

   423

	*  normal rail too */

   424

	if (disable) {

   425

		FOR_ALL_VEHICLES(v) {

   426

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

   427

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

   428

				*  so add there also normal rail compatibility */

   429

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

   430

				v->u.rail.railtype = RAILTYPE_RAIL;

   431

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

   432

			}

   433

		}

   434

	}

   435

   436

	/* setup total power for trains */

   437

	FOR_ALL_VEHICLES(v) {

   438

		/* power is cached only for front engines */

   439

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

   440

	}

   441

   442

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

   443

   444

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

   445

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

   446

	* extended, though. */

   447

	ReinitGuiAfterToggleElrail(disable);

   448

	return 0;

   449

}