--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/src/landscape.cpp Wed Jan 10 18:12:09 2007 +0000
@@ -0,0 +1,731 @@
+/* $Id$ */
+
+#include "stdafx.h"
+#include "openttd.h"
+#include "bridge_map.h"
+#include "heightmap.h"
+#include "clear_map.h"
+#include "functions.h"
+#include "map.h"
+#include "player.h"
+#include "spritecache.h"
+#include "table/sprites.h"
+#include "tile.h"
+#include <stdarg.h>
+#include "viewport.h"
+#include "command.h"
+#include "vehicle.h"
+#include "variables.h"
+#include "void_map.h"
+#include "water_map.h"
+#include "tgp.h"
+#include "genworld.h"
+#include "heightmap.h"
+
+extern const TileTypeProcs
+ _tile_type_clear_procs,
+ _tile_type_rail_procs,
+ _tile_type_road_procs,
+ _tile_type_town_procs,
+ _tile_type_trees_procs,
+ _tile_type_station_procs,
+ _tile_type_water_procs,
+ _tile_type_dummy_procs,
+ _tile_type_industry_procs,
+ _tile_type_tunnelbridge_procs,
+ _tile_type_unmovable_procs;
+
+const TileTypeProcs * const _tile_type_procs[16] = {
+ &_tile_type_clear_procs,
+ &_tile_type_rail_procs,
+ &_tile_type_road_procs,
+ &_tile_type_town_procs,
+ &_tile_type_trees_procs,
+ &_tile_type_station_procs,
+ &_tile_type_water_procs,
+ &_tile_type_dummy_procs,
+ &_tile_type_industry_procs,
+ &_tile_type_tunnelbridge_procs,
+ &_tile_type_unmovable_procs,
+};
+
+/* landscape slope => sprite */
+const byte _tileh_to_sprite[32] = {
+ 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 0,
+ 0, 0, 0, 0, 0, 0, 0, 16, 0, 0, 0, 17, 0, 15, 18, 0,
+};
+
+const byte _inclined_tileh[] = {
+ SLOPE_SW, SLOPE_NW, SLOPE_SW, SLOPE_SE, SLOPE_NE, SLOPE_SE, SLOPE_NE, SLOPE_NW,
+ SLOPE_E, SLOPE_N, SLOPE_W, SLOPE_S,
+ SLOPE_NWS, SLOPE_WSE, SLOPE_SEN, SLOPE_ENW
+};
+
+
+uint GetPartialZ(int x, int y, Slope corners)
+{
+ int z = 0;
+
+ switch (corners) {
+ case SLOPE_W:
+ if (x - y >= 0)
+ z = (x - y) >> 1;
+ break;
+
+ case SLOPE_S:
+ y^=0xF;
+ if ( (x - y) >= 0)
+ z = (x - y) >> 1;
+ break;
+
+ case SLOPE_SW:
+ z = (x>>1) + 1;
+ break;
+
+ case SLOPE_E:
+ if (y - x >= 0)
+ z = (y - x) >> 1;
+ break;
+
+ case SLOPE_EW:
+ case SLOPE_NS:
+ case SLOPE_ELEVATED:
+ z = 4;
+ break;
+
+ case SLOPE_SE:
+ z = (y>>1) + 1;
+ break;
+
+ case SLOPE_WSE:
+ z = 8;
+ y^=0xF;
+ if (x - y < 0)
+ z += (x - y) >> 1;
+ break;
+
+ case SLOPE_N:
+ y ^= 0xF;
+ if (y - x >= 0)
+ z = (y - x) >> 1;
+ break;
+
+ case SLOPE_NW:
+ z = (y^0xF)>>1;
+ break;
+
+ case SLOPE_NWS:
+ z = 8;
+ if (x - y < 0)
+ z += (x - y) >> 1;
+ break;
+
+ case SLOPE_NE:
+ z = (x^0xF)>>1;
+ break;
+
+ case SLOPE_ENW:
+ z = 8;
+ y ^= 0xF;
+ if (y - x < 0)
+ z += (y - x) >> 1;
+ break;
+
+ case SLOPE_SEN:
+ z = 8;
+ if (y - x < 0)
+ z += (y - x) >> 1;
+ break;
+
+ case SLOPE_STEEP_S:
+ z = 1 + ((x+y)>>1);
+ break;
+
+ case SLOPE_STEEP_W:
+ z = 1 + ((x+(y^0xF))>>1);
+ break;
+
+ case SLOPE_STEEP_N:
+ z = 1 + (((x^0xF)+(y^0xF))>>1);
+ break;
+
+ case SLOPE_STEEP_E:
+ z = 1 + (((x^0xF)+(y^0xF))>>1);
+ break;
+
+ default: break;
+ }
+
+ return z;
+}
+
+uint GetSlopeZ(int x, int y)
+{
+ TileIndex tile = TileVirtXY(x, y);
+
+ return _tile_type_procs[GetTileType(tile)]->get_slope_z_proc(tile, x, y);
+}
+
+
+static Slope GetFoundationSlope(TileIndex tile, uint* z)
+{
+ Slope tileh = GetTileSlope(tile, z);
+ Slope slope = _tile_type_procs[GetTileType(tile)]->get_slope_tileh_proc(tile, tileh);
+
+ // Flatter slope -> higher base height
+ if (slope < tileh) *z += TILE_HEIGHT;
+ return slope;
+}
+
+
+static bool HasFoundationNW(TileIndex tile, Slope slope_here, uint z_here)
+{
+ uint z;
+ Slope slope = GetFoundationSlope(TILE_ADDXY(tile, 0, -1), &z);
+
+ return
+ (
+ z_here + (slope_here & SLOPE_N ? TILE_HEIGHT : 0) + (slope_here == SLOPE_STEEP_N ? TILE_HEIGHT : 0) >
+ z + (slope & SLOPE_E ? TILE_HEIGHT : 0) + (slope == SLOPE_STEEP_E ? TILE_HEIGHT : 0)
+ ) || (
+ z_here + (slope_here & SLOPE_W ? TILE_HEIGHT : 0) + (slope_here == SLOPE_STEEP_W ? TILE_HEIGHT : 0) >
+ z + (slope & SLOPE_S ? TILE_HEIGHT : 0) + (slope == SLOPE_STEEP_S ? TILE_HEIGHT : 0)
+ );
+}
+
+
+static bool HasFoundationNE(TileIndex tile, Slope slope_here, uint z_here)
+{
+ uint z;
+ Slope slope = GetFoundationSlope(TILE_ADDXY(tile, -1, 0), &z);
+
+ return
+ (
+ z_here + (slope_here & SLOPE_N ? TILE_HEIGHT : 0) + (slope_here == SLOPE_STEEP_N ? TILE_HEIGHT : 0) >
+ z + (slope & SLOPE_W ? TILE_HEIGHT : 0) + (slope == SLOPE_STEEP_W ? TILE_HEIGHT : 0)
+ ) || (
+ z_here + (slope_here & SLOPE_E ? TILE_HEIGHT : 0) + (slope_here == SLOPE_STEEP_E ? TILE_HEIGHT : 0) >
+ z + (slope & SLOPE_S ? TILE_HEIGHT : 0) + (slope == SLOPE_STEEP_S ? TILE_HEIGHT : 0)
+ );
+}
+
+
+void DrawFoundation(TileInfo *ti, uint f)
+{
+ uint32 sprite_base = SPR_SLOPES_BASE - 15;
+ Slope slope;
+ uint z;
+
+ slope = GetFoundationSlope(ti->tile, &z);
+ if (!HasFoundationNW(ti->tile, slope, z)) sprite_base += 22;
+ if (!HasFoundationNE(ti->tile, slope, z)) sprite_base += 44;
+
+ if (IsSteepSlope(ti->tileh)) {
+ uint32 lower_base;
+
+ // Lower part of foundation
+ lower_base = sprite_base;
+ if (lower_base == SPR_SLOPES_BASE - 15) lower_base = SPR_FOUNDATION_BASE;
+ AddSortableSpriteToDraw(
+ lower_base + (ti->tileh & ~SLOPE_STEEP), ti->x, ti->y, 16, 16, 7, ti->z
+ );
+ ti->z += TILE_HEIGHT;
+ ti->tileh = _inclined_tileh[f - 15];
+ if (f < 15 + 8) {
+ // inclined
+ AddSortableSpriteToDraw(sprite_base + f, ti->x, ti->y, 16, 16, 1, ti->z);
+ OffsetGroundSprite(31, 9);
+ } else if (f >= 15 + 8 + 4) {
+ // three corners raised
+ uint32 upper = sprite_base + 15 + (f - 15 - 8 - 4) * 2;
+
+ AddSortableSpriteToDraw(upper, ti->x, ti->y, 16, 16, 1, ti->z);
+ AddChildSpriteScreen(upper + 1, 31, 9);
+ OffsetGroundSprite(31, 9);
+ } else {
+ // one corner raised
+ OffsetGroundSprite(31, 1);
+ }
+ } else {
+ if (f < 15) {
+ // leveled foundation
+ // Use the original slope sprites if NW and NE borders should be visible
+ if (sprite_base == SPR_SLOPES_BASE - 15) sprite_base = SPR_FOUNDATION_BASE;
+
+ AddSortableSpriteToDraw(sprite_base + f, ti->x, ti->y, 16, 16, 7, ti->z);
+ ti->z += TILE_HEIGHT;
+ ti->tileh = SLOPE_FLAT;
+ OffsetGroundSprite(31, 1);
+ } else {
+ // inclined foundation
+ AddSortableSpriteToDraw(sprite_base + f, ti->x, ti->y, 16, 16, 1, ti->z);
+ ti->tileh = _inclined_tileh[f - 15];
+ OffsetGroundSprite(31, 9);
+ }
+ }
+}
+
+void DoClearSquare(TileIndex tile)
+{
+ MakeClear(tile, CLEAR_GRASS, _generating_world ? 3 : 0);
+ MarkTileDirtyByTile(tile);
+}
+
+uint32 GetTileTrackStatus(TileIndex tile, TransportType mode)
+{
+ return _tile_type_procs[GetTileType(tile)]->get_tile_track_status_proc(tile, mode);
+}
+
+void ChangeTileOwner(TileIndex tile, byte old_player, byte new_player)
+{
+ _tile_type_procs[GetTileType(tile)]->change_tile_owner_proc(tile, old_player, new_player);
+}
+
+void GetAcceptedCargo(TileIndex tile, AcceptedCargo ac)
+{
+ memset(ac, 0, sizeof(AcceptedCargo));
+ _tile_type_procs[GetTileType(tile)]->get_accepted_cargo_proc(tile, ac);
+}
+
+void AnimateTile(TileIndex tile)
+{
+ _tile_type_procs[GetTileType(tile)]->animate_tile_proc(tile);
+}
+
+void ClickTile(TileIndex tile)
+{
+ _tile_type_procs[GetTileType(tile)]->click_tile_proc(tile);
+}
+
+void GetTileDesc(TileIndex tile, TileDesc *td)
+{
+ _tile_type_procs[GetTileType(tile)]->get_tile_desc_proc(tile, td);
+}
+
+/** Clear a piece of landscape
+ * @param tile tile to clear
+ * @param p1 unused
+ * @param p2 unused
+ */
+int32 CmdLandscapeClear(TileIndex tile, uint32 flags, uint32 p1, uint32 p2)
+{
+ SET_EXPENSES_TYPE(EXPENSES_CONSTRUCTION);
+
+ return _tile_type_procs[GetTileType(tile)]->clear_tile_proc(tile, flags);
+}
+
+/** Clear a big piece of landscape
+ * @param tile end tile of area dragging
+ * @param p1 start tile of area dragging
+ * @param p2 unused
+ */
+int32 CmdClearArea(TileIndex tile, uint32 flags, uint32 p1, uint32 p2)
+{
+ int32 cost, ret, money;
+ int ex;
+ int ey;
+ int sx,sy;
+ int x,y;
+ bool success = false;
+
+ if (p1 >= MapSize()) return CMD_ERROR;
+
+ SET_EXPENSES_TYPE(EXPENSES_CONSTRUCTION);
+
+ // make sure sx,sy are smaller than ex,ey
+ ex = TileX(tile);
+ ey = TileY(tile);
+ sx = TileX(p1);
+ sy = TileY(p1);
+ if (ex < sx) intswap(ex, sx);
+ if (ey < sy) intswap(ey, sy);
+
+ money = GetAvailableMoneyForCommand();
+ cost = 0;
+
+ for (x = sx; x <= ex; ++x) {
+ for (y = sy; y <= ey; ++y) {
+ ret = DoCommand(TileXY(x, y), 0, 0, flags & ~DC_EXEC, CMD_LANDSCAPE_CLEAR);
+ if (CmdFailed(ret)) continue;
+ cost += ret;
+ success = true;
+
+ if (flags & DC_EXEC) {
+ if (ret > 0 && (money -= ret) < 0) {
+ _additional_cash_required = ret;
+ return cost - ret;
+ }
+ DoCommand(TileXY(x, y), 0, 0, flags, CMD_LANDSCAPE_CLEAR);
+
+ // draw explosion animation...
+ if ((x == sx || x == ex) && (y == sy || y == ey)) {
+ // big explosion in each corner, or small explosion for single tiles
+ CreateEffectVehicleAbove(x * TILE_SIZE + TILE_SIZE / 2, y * TILE_SIZE + TILE_SIZE / 2, 2,
+ sy == ey && sx == ex ? EV_EXPLOSION_SMALL : EV_EXPLOSION_LARGE
+ );
+ }
+ }
+ }
+ }
+
+ return (success) ? cost : CMD_ERROR;
+}
+
+
+#define TILELOOP_BITS 4
+#define TILELOOP_SIZE (1 << TILELOOP_BITS)
+#define TILELOOP_ASSERTMASK ((TILELOOP_SIZE-1) + ((TILELOOP_SIZE-1) << MapLogX()))
+#define TILELOOP_CHKMASK (((1 << (MapLogX() - TILELOOP_BITS))-1) << TILELOOP_BITS)
+
+void RunTileLoop(void)
+{
+ TileIndex tile;
+ uint count;
+
+ tile = _cur_tileloop_tile;
+
+ assert( (tile & ~TILELOOP_ASSERTMASK) == 0);
+ count = (MapSizeX() / TILELOOP_SIZE) * (MapSizeY() / TILELOOP_SIZE);
+ do {
+ _tile_type_procs[GetTileType(tile)]->tile_loop_proc(tile);
+
+ if (TileX(tile) < MapSizeX() - TILELOOP_SIZE) {
+ tile += TILELOOP_SIZE; /* no overflow */
+ } else {
+ tile = TILE_MASK(tile - TILELOOP_SIZE * (MapSizeX() / TILELOOP_SIZE - 1) + TileDiffXY(0, TILELOOP_SIZE)); /* x would overflow, also increase y */
+ }
+ } while (--count);
+ assert( (tile & ~TILELOOP_ASSERTMASK) == 0);
+
+ tile += 9;
+ if (tile & TILELOOP_CHKMASK)
+ tile = (tile + MapSizeX()) & TILELOOP_ASSERTMASK;
+ _cur_tileloop_tile = tile;
+}
+
+void InitializeLandscape(void)
+{
+ uint maxx = MapMaxX();
+ uint maxy = MapMaxY();
+ uint sizex = MapSizeX();
+ uint x;
+ uint y;
+
+ for (y = 0; y < maxy; y++) {
+ for (x = 0; x < maxx; x++) {
+ MakeClear(sizex * y + x, CLEAR_GRASS, 3);
+ SetTileHeight(sizex * y + x, 0);
+ _m[sizex * y + x].extra = 0;
+ ClearBridgeMiddle(sizex * y + x);
+ }
+ MakeVoid(sizex * y + x);
+ }
+ for (x = 0; x < sizex; x++) MakeVoid(sizex * y + x);
+}
+
+void ConvertGroundTilesIntoWaterTiles(void)
+{
+ TileIndex tile;
+ uint z;
+ Slope slope;
+
+ for (tile = 0; tile < MapSize(); ++tile) {
+ slope = GetTileSlope(tile, &z);
+ if (IsTileType(tile, MP_CLEAR) && z == 0) {
+ /* Make both water for tiles at level 0
+ * and make shore, as that looks much better
+ * during the generation. */
+ switch (slope) {
+ case SLOPE_FLAT:
+ MakeWater(tile);
+ break;
+
+ case SLOPE_N:
+ case SLOPE_E:
+ case SLOPE_S:
+ case SLOPE_W:
+ case SLOPE_NW:
+ case SLOPE_SW:
+ case SLOPE_SE:
+ case SLOPE_NE:
+ MakeShore(tile);
+ break;
+
+ default:
+ break;
+ }
+ }
+ }
+}
+
+static const byte _genterrain_tbl_1[5] = { 10, 22, 33, 37, 4 };
+static const byte _genterrain_tbl_2[5] = { 0, 0, 0, 0, 33 };
+
+static void GenerateTerrain(int type, int flag)
+{
+ uint32 r;
+ uint x;
+ uint y;
+ uint w;
+ uint h;
+ const Sprite* template;
+ const byte *p;
+ Tile* tile;
+ byte direction;
+
+ r = Random();
+ template = GetSprite((((r >> 24) * _genterrain_tbl_1[type]) >> 8) + _genterrain_tbl_2[type] + 4845);
+
+ x = r & MapMaxX();
+ y = (r >> MapLogX()) & MapMaxY();
+
+
+ if (x < 2 || y < 2) return;
+
+ direction = GB(r, 22, 2);
+ if (direction & 1) {
+ w = template->height;
+ h = template->width;
+ } else {
+ w = template->width;
+ h = template->height;
+ }
+ p = template->data;
+
+ if (flag & 4) {
+ uint xw = x * MapSizeY();
+ uint yw = y * MapSizeX();
+ uint bias = (MapSizeX() + MapSizeY()) * 16;
+
+ switch (flag & 3) {
+ case 0:
+ if (xw + yw > MapSize() - bias) return;
+ break;
+
+ case 1:
+ if (yw < xw + bias) return;
+ break;
+
+ case 2:
+ if (xw + yw < MapSize() + bias) return;
+ break;
+
+ case 3:
+ if (xw < yw + bias) return;
+ break;
+ }
+ }
+
+ if (x + w >= MapMaxX() - 1) return;
+ if (y + h >= MapMaxY() - 1) return;
+
+ tile = &_m[TileXY(x, y)];
+
+ switch (direction) {
+ case 0:
+ do {
+ Tile* tile_cur = tile;
+ uint w_cur;
+
+ for (w_cur = w; w_cur != 0; --w_cur) {
+ if (*p >= tile_cur->type_height) tile_cur->type_height = *p;
+ p++;
+ tile_cur++;
+ }
+ tile += TileDiffXY(0, 1);
+ } while (--h != 0);
+ break;
+
+ case 1:
+ do {
+ Tile* tile_cur = tile;
+ uint h_cur;
+
+ for (h_cur = h; h_cur != 0; --h_cur) {
+ if (*p >= tile_cur->type_height) tile_cur->type_height = *p;
+ p++;
+ tile_cur += TileDiffXY(0, 1);
+ }
+ tile++;
+ } while (--w != 0);
+ break;
+
+ case 2:
+ tile += TileDiffXY(w - 1, 0);
+ do {
+ Tile* tile_cur = tile;
+ uint w_cur;
+
+ for (w_cur = w; w_cur != 0; --w_cur) {
+ if (*p >= tile_cur->type_height) tile_cur->type_height = *p;
+ p++;
+ tile_cur--;
+ }
+ tile += TileDiffXY(0, 1);
+ } while (--h != 0);
+ break;
+
+ case 3:
+ tile += TileDiffXY(0, h - 1);
+ do {
+ Tile* tile_cur = tile;
+ uint h_cur;
+
+ for (h_cur = h; h_cur != 0; --h_cur) {
+ if (*p >= tile_cur->type_height) tile_cur->type_height = *p;
+ p++;
+ tile_cur -= TileDiffXY(0, 1);
+ }
+ tile++;
+ } while (--w != 0);
+ break;
+ }
+}
+
+
+#include "table/genland.h"
+
+static void CreateDesertOrRainForest(void)
+{
+ TileIndex tile;
+ TileIndex update_freq = MapSize() / 4;
+ const TileIndexDiffC *data;
+ uint i;
+
+ for (tile = 0; tile != MapSize(); ++tile) {
+ if ((tile % update_freq) == 0) IncreaseGeneratingWorldProgress(GWP_LANDSCAPE);
+
+ for (data = _make_desert_or_rainforest_data;
+ data != endof(_make_desert_or_rainforest_data); ++data) {
+ TileIndex t = TILE_MASK(tile + ToTileIndexDiff(*data));
+ if (TileHeight(t) >= 4 || IsTileType(t, MP_WATER)) break;
+ }
+ if (data == endof(_make_desert_or_rainforest_data))
+ SetTropicZone(tile, TROPICZONE_DESERT);
+ }
+
+ for (i = 0; i != 256; i++) {
+ if ((i % 64) == 0) IncreaseGeneratingWorldProgress(GWP_LANDSCAPE);
+
+ RunTileLoop();
+ }
+
+ for (tile = 0; tile != MapSize(); ++tile) {
+ if ((tile % update_freq) == 0) IncreaseGeneratingWorldProgress(GWP_LANDSCAPE);
+
+ for (data = _make_desert_or_rainforest_data;
+ data != endof(_make_desert_or_rainforest_data); ++data) {
+ TileIndex t = TILE_MASK(tile + ToTileIndexDiff(*data));
+ if (IsTileType(t, MP_CLEAR) && IsClearGround(t, CLEAR_DESERT)) break;
+ }
+ if (data == endof(_make_desert_or_rainforest_data))
+ SetTropicZone(tile, TROPICZONE_RAINFOREST);
+ }
+}
+
+void GenerateLandscape(byte mode)
+{
+ const int gwp_desert_amount = 4 + 8;
+ uint i;
+ uint flag;
+ uint32 r;
+
+ if (mode == GW_HEIGHTMAP) {
+ SetGeneratingWorldProgress(GWP_LANDSCAPE, (_opt.landscape == LT_DESERT) ? 1 + gwp_desert_amount : 1);
+ LoadHeightmap(_file_to_saveload.name);
+ IncreaseGeneratingWorldProgress(GWP_LANDSCAPE);
+ } else if (_patches.land_generator == LG_TERRAGENESIS) {
+ SetGeneratingWorldProgress(GWP_LANDSCAPE, (_opt.landscape == LT_DESERT) ? 3 + gwp_desert_amount : 3);
+ GenerateTerrainPerlin();
+ } else {
+ switch (_opt.landscape) {
+ case LT_HILLY:
+ SetGeneratingWorldProgress(GWP_LANDSCAPE, 2);
+
+ for (i = ScaleByMapSize((Random() & 0x7F) + 950); i != 0; --i) {
+ GenerateTerrain(2, 0);
+ }
+ IncreaseGeneratingWorldProgress(GWP_LANDSCAPE);
+
+ r = Random();
+ flag = GB(r, 0, 2) | 4;
+ for (i = ScaleByMapSize(GB(r, 16, 7) + 450); i != 0; --i) {
+ GenerateTerrain(4, flag);
+ }
+ IncreaseGeneratingWorldProgress(GWP_LANDSCAPE);
+ break;
+
+ case LT_DESERT:
+ SetGeneratingWorldProgress(GWP_LANDSCAPE, 3 + gwp_desert_amount);
+
+ for (i = ScaleByMapSize((Random() & 0x7F) + 170); i != 0; --i) {
+ GenerateTerrain(0, 0);
+ }
+ IncreaseGeneratingWorldProgress(GWP_LANDSCAPE);
+
+ r = Random();
+ flag = GB(r, 0, 2) | 4;
+ for (i = ScaleByMapSize(GB(r, 16, 8) + 1700); i != 0; --i) {
+ GenerateTerrain(0, flag);
+ }
+ IncreaseGeneratingWorldProgress(GWP_LANDSCAPE);
+
+ flag ^= 2;
+
+ for (i = ScaleByMapSize((Random() & 0x7F) + 410); i != 0; --i) {
+ GenerateTerrain(3, flag);
+ }
+ IncreaseGeneratingWorldProgress(GWP_LANDSCAPE);
+ break;
+
+ default:
+ SetGeneratingWorldProgress(GWP_LANDSCAPE, 1);
+
+ i = ScaleByMapSize((Random() & 0x7F) + (3 - _opt.diff.quantity_sea_lakes) * 256 + 100);
+ for (; i != 0; --i) {
+ GenerateTerrain(_opt.diff.terrain_type, 0);
+ }
+ IncreaseGeneratingWorldProgress(GWP_LANDSCAPE);
+ break;
+ }
+ }
+
+ ConvertGroundTilesIntoWaterTiles();
+
+ if (_opt.landscape == LT_DESERT) CreateDesertOrRainForest();
+}
+
+void OnTick_Town(void);
+void OnTick_Trees(void);
+void OnTick_Station(void);
+void OnTick_Industry(void);
+
+void OnTick_Players(void);
+void OnTick_Train(void);
+
+void CallLandscapeTick(void)
+{
+ OnTick_Town();
+ OnTick_Trees();
+ OnTick_Station();
+ OnTick_Industry();
+
+ OnTick_Players();
+ OnTick_Train();
+}
+
+TileIndex AdjustTileCoordRandomly(TileIndex a, byte rng)
+{
+ int rn = rng;
+ uint32 r = Random();
+
+ return TILE_MASK(TileXY(
+ TileX(a) + (GB(r, 0, 8) * rn * 2 >> 8) - rn,
+ TileY(a) + (GB(r, 8, 8) * rn * 2 >> 8) - rn
+ ));
+}
+
+bool IsValidTile(TileIndex tile)
+{
+ return (tile < MapSizeX() * MapMaxY() && TileX(tile) != MapMaxX());
+}