OpenTTD Landscape Internals
Author: Marcin Grzegorczyk
Description: Structure of OpenTTD (OTTD) landscape arrays

### Landscape

Five attributes hold the information about a tile. These attributes are referred to as "type_height", "m1", "m2", "m3", "m4" and "m5". The most important value is the class of a tile, stored in the upper 4 bits of the type_height array. The lower 4 bits are used to encode the height and slope data. For a graphical represenation of the tile-layout have a look at Landscape grid page.

OTTD's class-specific periodic tile processing routine is called once every +256 ticks for each tile.

Class | Meaning & details of encoding
--- | ---
- `0` | m5 bits 4..0: tile type:
  `00` | bare land
  `01` | 1/3 grass
  `02` | 2/3 grass
  `03` | full grass
  `07` | rough land
  `0B` | rocks
  `0F` | fields; type of fields in m3 bits 3..0 (legal values: 0 through 9)
  `10` | 1/4 snow
  `11` | 2/4 snow
  `12` | 3/4 snow
  `13` | full snow
  `15` | partial desert
  `17` | full desert
m5 bits 7..5: update counter, incremented on every periodic processing for tile types other than `03`, `07`, `0B` and `10` and above, on wraparound the tile is updated (for fields, the type of fields in m3 is increased, for other types the tile type in m5 is increased) (for snow and desert, these bits are not used, tile is updated on every periodic processing) m1: owner of the tile (normally `10`) m4 bits 7..5: type of hedge on the SW border of the tile (1 through 6, or 0=none); bits 4..2: same for the SE border
- `1` | m5 bit 7 clear: railway track m5 bits 0..5: track layout: bit set = track present:
  bit 0: | in the X direction
  bit 1: | in the Y direction
  bit 2: | in the north corner (direction W-E)
  bit 3: | in the south corner (direction W-E)
  bit 4: | in the west corner (direction N-S)
  bit 5: | in the east corner (direction N-S)
- - - m5 bit 6 set = with signals: m3 bits 7..4: bit set = signal present: For track in the X direction:
      bit 6: | signal in the SW direction
      bit 7: | signal in the NE direction
    - For track in the Y direction:
      bit 6: | signal in the NW direction
      bit 7: | signal in the SE direction
    - For tracks in the W-E direction:
      bit 4: | signal in the W direction on the track in the S corner
      bit 5: | signal in the E direction on the track in the S corner
      bit 6: | signal in the W direction on the track in the N corner
      bit 7: | signal in the E direction on the track in the N corner
    - For tracks in the N-S direction:
      bit 4: | signal in the S direction on the track in the E corner
      bit 5: | signal in the N direction on the track in the E corner
      bit 6: | signal in the S direction on the track in the W corner
      bit 7: | signal in the N direction on the track in the W corner
  - m2 bits 7..4: bit clear = signal shows red; same bits as in m3 OpenTTD bits in m4:
    bits 2..0: | type of signal:
    `000`: | normal signals
    `001`: | pre-signals
    `010`: | exit-signals
    `011`: | combo-signals
    `100`: | PBS signals
    bit 3: | set = semaphore signals, clear = light signals
- m1: owner of the track m2 bits 0..3:
  `0` | on bare land
  `1` | on grass, no fences
  `2` | fence on the NW side
  `3` | fence on the SE side
  `4` | fences on the NW and SE sides
  `5` | fence on the NE side
  `6` | fence on the SW side
  `7` | fences on the NE and SW sides
  `8` | fence on the E side (track in the W corner)
  `9` | fence on the W side (track in the E corner)
  `A` | fence on the S side (track in the N corner)
  `B` | fence on the N side (track in the S corner)
  `C` | on snow or desert
- m3 bits 0..3 = track type: `0` - conventional railway, `1` - monorail, `2` - maglev m4 bits 4..7 = Pbs reserved status:
  `bits 4..6` | 'Track'number of reserved track + 1, if this is zero it means nothing is reserved on this tile
  `bit 7` | If this is set, then the opposite track ('Track'number^1) is also reserved
m5 bits 7 and 6 set: railway depot / checkpoints m5 value C0..C3: railway depot m5 bits 1..0 - direction: exit towards: `00` = NE, `01` = SE, `02` = SW, `03` = NW m5 value C4..C5: checkpoint bit 0: clear = in X direction, set = in Y direction m1: owner of the depot / checkpoint m2: For waypoints, index into the array of waypoints. m3 bits 0..3 = track type m3 bit 4 = use custom sprite (valid only for the checkpoint) m3 bit 6 = track on this tile is reserved by pbs m4 bits 0..3 = ground type, as per m2 bits 0..3 for railway tiles.
- `2` | m5 bits 7..4 clear: road m5 bits 3..0: road layout: bit set = road piece present:
  bit 0: | NW piece
  bit 1: | SW piece
  bit 2: | SE piece
  bit 3: | NE piece
m1: owner of the road m2: Index into the array of towns, 0 for non-town roads m4 bits 0..3: counter for the roadworks m4 bits 4..6: `0` - on bare land, `1` - on grass, `2` - paved, `3` - with streetlights, `5` - tree-lined, `6` - on grass with road works, `7` - paved with road works m4 bit 7 set = on snow or desert m5 bit 4 set, bits 7..5 clear: level crossing m5 bit 3: clear - road in the X direction, set - road in the Y direction (railway track always perpendicular) m5 bit 2: set if crossing lights are on m5 bit 0: set if rail track is reserved by pbs m1: owner of the railway track m2: Index into the array of towns, 0 for non-town roads m3 bits 0..7: owner of the road m4 bits 3..0: track type m4 bits 4..6: `0` - on bare land, `1` - on grass, `2` or higher - paved m4 bit 7 set = on snow or desert m5 bit 5 set: road depot m5 bits 3..0 - direction: exit towards: `0` = NE, `1` = SE, `2` = SW, `3` = NW m1: owner of the depot m4 bit 7 set = on snow or desert (not displayed, but set internally)
- `3` | Town building m2: Index into the array of towns m4: town building type: Note: In the climate list, 'sub-arctic' means below the snow line, and 'snow' means above the snow line in the sub-arctic climate.
  Type | Size | Climates | Description
  --- | --- | --- | ---
  `00` | 1×1 | temperate | tall office block
  `01` | 1×1 | temperate | office block
  `02` | 1×1 | temperate | small block of flats
  `03` | 1×1 | temperate | church
  `04` | 1×1 | temperate, sub-arctic, sub-tropical | large office block
  `05` | 1×1 | snow | large office block
  `06` | 1×1 | temperate | town houses
  `07`..`08` | 1×2 | temperate | hotel
  `09` | 1×1 | temperate, sub-arctic, sub-tropical | statue
  `0A` | 1×1 | temperate, sub-arctic, sub-tropical | fountain
  `0B` | 1×1 | temperate | park (with a pond)
  `0C` | 1×1 | temperate | park (with an alley)
  `0D` | 1×1 | temperate | office block
  `0E`..`10` | 1×1 | temperate | various types of shops and offices
  `11` | 1×1 | temperate, sub-arctic, sub-tropical | modern office building
  `12` | 1×1 | temperate | warehouse
  `13` | 1×1 | temperate | office block (with spiral stairway on the side)
  `14`..`17` | 2×2 | temperate | stadium
  `18` | 1×1 | temperate | old houses
  `19` | 1×1 | temperate | cottages
  `1A` | 1×1 | temperate | houses
  `1B` | 1×1 | temperate | flats
  `1C` | 1×1 | temperate | tall office block
  `1D` | 1×1 | temperate | shops and offices
  `1E` | 1×1 | temperate, sub-tropical | shops and offices
  `1F` | 1×1 | temperate | theatre
  `20`..`23` | 2×2 | temperate, sub-arctic, sub-tropical | stadium (modern style)
  `24` | 1×1 | temperate, sub-arctic, sub-tropical | offices (the modern 'vertical tube' style)
  `25` | 1×1 | sub-arctic | houses
  `26` | 1×1 | snow | houses
  `27` | 1×1 | temperate | cinema
  `28`..`2B` | 2×2 | temperate | shopping mall
  `2C` | 1×1 | sub-arctic | flats
  `2D` | 1×1 | snow | flats
  `2E` | 1×1 | sub-arctic | houses
  `2F` | 1×1 | snow | houses
  `30` | 1×1 | sub-arctic | houses
  `31` | 1×1 | snow | houses
  `32` | 1×1 | sub-arctic, sub-tropical | tall office block
  `33` | 1×1 | snow | tall office block
  `34` | 1×1 | sub-arctic | tall office block
  `35` | 1×1 | snow | tall office block
  `36` | 1×1 | sub-arctic, sub-tropical | tall office block
  `37` | 1×1 | snow | tall office block
  `38` | 1×1 | sub-arctic | houses
  `39` | 1×1 | snow | houses
  `3A` | 1×1 | sub-arctic | shops and offices
  `3B` | 1×1 | snow | shops and offices
  `3C` | 1×1 | sub-arctic | church
  `3D` | 1×1 | snow | church
  `3E` | 1×1 | sub-arctic | houses
  `3F` | 1×1 | snow | houses
  `40` | 1×1 | sub-arctic | shops and offices
  `41` | 1×1 | snow | shops and offices
  `42`..`43` | 1×2 | sub-arctic | hotel
  `44`..`45` | 1×2 | snow | hotel
  `46` | 1×1 | sub-arctic, sub-tropical | shops and offices
  `47` | 1×1 | snow | shops and offices
  `48` | 1×1 | sub-arctic | tall office block
  `49` | 1×1 | snow | tall office block
  `4A`..`4B` | 2×1 | sub-arctic | tall office block
  `4C`..`4D` | 2×1 | snow | tall office block
  `4E` | 1×1 | sub-tropical | houses (with a tree in a corner)
  `4F`, `50` | 1×1 | sub-tropical | houses
  `51` | 1×1 | sub-tropical | houses (suburb-type)
  `52` | 1×1 | sub-tropical | flats
  `53` | 1×1 | sub-tropical | church
  `54` | 1×1 | sub-tropical | houses (with two trees in front)
  `55`, `56` | 1×1 | sub-tropical | flats
  `57`..`58` | 2×1 | sub-tropical | tall office block
  `59` | 1×1 | sub-tropical | flats
  `5A` | 1×1 | sub-tropical | tall office block
  `5B` | 1×1 | toyland | church
  `5C`..`61` | 1×1 | toyland | various types of toyland houses
  `62` | 1×1 | toyland | tall office block
  `63`..`64` | 1×2 | toyland | houses ('shoe' style)
  `65` | 1×1 | toyland | tall office block
  `66` | 1×1 | toyland | igloo
  `67` | 1×1 | toyland | tepees
  `68`, `69` | 1×1 | toyland | shops and offices
  `6A` | 1×1 | toyland | tall office block
  `6B` | 1×1 | toyland | statue
  `6C` | 1×1 | toyland | teapot-house
  `6D` | 1×1 | toyland | piggy-bank
m3 bits 7..6: stage of construction (`3` = completed) m5 bits 2..0: construction counter, for buildings under construction incremented on every periodic tile processing, on wraparound the stage of construction in m3 is increased for large office blocks (types `04` and `05`): m1 bits 6..0: position of the lift m1 bit 7: if set the lift is moving m5 bit 7: if set then m5 bits 5..0 hold the final position of the lift divided by 6 (valid values 0..6 except 1)
- `4` | Trees m5 bits 7..6: number of trees minus one m5 bits 2..0: growth status: `0`..`2` - one of trees is growing, `3` - all trees are fully grown, `4`..`6` - one of trees is withering m3 bits 7..0: type of trees:
  `00`..`0B` | temperate climate trees
  `0C`..`13` | sub-arctic climate trees
  `14`..`1A` | rainforest trees
  `1B` | cactus plants
  `1C`..`1F` | sub-tropical climate, non-rainforest, non-desert trees
  `20`..`28` | toyland trees
- (note: the actually displayed set of trees depends on both type and number of trees) m4 bits 7..5: type of hedge on the SW border of the tile (1 through 6, or 0=none) m4 bits 4..2: type of hedge on the SE border of the tile (1 through 6, or 0=none) m2 bits 5..4:
  `0` | on grass
  `1` | on rough land
  `2` | on snow or desert; m2 bits 7..6 - amount of snow or desert (for desert always set to 3 in TTD)
m2 bits 3..0: update counter, incremented on every periodic processing, on wraparound the growth status is updated (or, if it's `3`, a random action is taken) m1: owner (normally `10`)
- `5` | Station tile m5: tile type:
  `00`..`07` | railway station `00`..`01` - open platform, `02`..`03` - open platform with station building, `04`....`07` - roofed platform bit 0: clear = in X direction, set = in Y direction
  `08`..`33` | large airport
  `0B` | pad 1
  `16`..`19` | runway middle
  `1A` | runway ending
  `1C` | control tower
  `20` | hangar
  `21` | pad 3
  `22` | pad 2
  `27`..`32` | radar (animated)
  `33` | transmitter
  The initial layout of a large airport is (rows in Y direction, columns in X direction):
      1F 1B 1E 33 26 1A
      09 24 0B 0C 0D 16
      21 1D 23 0E 0F 17
      09 22 0D 11 10 18
      09 08 14 13 12 19
      20 0A 15 1C 27 1A
  `34`..`41` | small airport
  `3A`..`3D` | field with the wind meter (animated)
  `3E` | runway south ending
  `3F` | runway middle
  `40` | runway north ending
  `41` | hangar
  The initial layout of a small airport is (rows in Y direction, columns in X direction):
      36 3A 40
      35 39 3F
      34 38 3F
      41 37 3E
  `42` | heliport
  `43`..`46` | lorry loading area; exit towards: `43` - NE, `44` - SE, `45` - SW, `46` - NW
  `47`..`4A` | bus station; exit towards: `47` - NE, `48` - SE, `49` - SW, `4A` - NW
  `4B` | oilfield
  `4C`..`51` | ship dock; `4C` - SW coast part, `4D` - NW coast part, `4E` - NE coast part, `4F` - SE coast part, `50` - X direction water part, `51` - Y direction water part
  `52` | buoy

- m1: owner of the station
- m2: index into the array of stations
- m3 bits 0..3: track type for railway stations, must be 0 for all the other stations
- m3 bit 4 = use custom sprite (valid only railway stations FOR NOW)
- m3 bit 6 set = track is reserved by pbs (railway stations only)
- m4 = custom station id
`6`

- m5: tile type:

  `00` | water
  `01` | coast or riverbank
  `10`..`1B` | canal locks
  `10` | middle part, (SW-NE direction)
  `11` | middle part, (NW-SE direction)
  `12` | middle part, (NE-SW direction)
  `13` | middle part, (SE-NW direction)
  `14` | lower part, (SW-NE direction)
  `15` | lower part, (NW-SE direction)
  `16` | lower part, (NE-SW direction)
  `17` | lower part, (SE-NW direction)
  `18` | upper part, (SW-NE direction)
  `19` | upper part, (NW-SE direction)
  `1A` | upper part, (NE-SW direction)
  `1B` | upper part, (SE-NW direction)
  `80`..`83` | ship depots
  `80` | ship depot, NE part (X direction)
  `81` | ship depot, SW part (X direction)
  `82` | ship depot, NW part (Y direction)
  `83` | ship depot, SE part (Y direction)

- m1: owner (for water and coasts normally `11`)

`7` Void

Tiles of this class form an invisible, one tile wide border at the south (bottom) edges of the map, so as to protect several algorithms from the consequences of a wraparound at the edges.

`8` Industry tile

- m5: type:
  (note: this is not the same as the industry type stored in the array of industries)

  `00`..`06` | coal mine
  `00` | wheel tower when not animated
  `01` | wheel tower when animated; animation state in m1 bits 5..0; m1 bit 6 set = sound already generated
  `07`..`0A` | power station
  `08` | chimney
  `0A` | transformer; animation progress in m1 bits 5..2 (valid range `0`..`7`)
  `0B`..`0F` | sawmill
  `10`..`11` | forest
  `11` | trees cut down
  `12`..`17` | oil refinery
  `18`..`1C` | oil rig
  `1D`..`20` | oil wells
  `1D` | not animated
  `1E`..`20` | various stages of animation; progress of animation in m1 bits 1..0
  `21`..`26` | farm
  `27`..`2A` | factory (temperate climate)
  `2B`..`2E` | printing works
  `2F`..`33` | copper ore mine
  `2F` | wheel tower when not animated
  `30` | wheel tower when animated; animation state in m1 bits 5..0; m1 bit 6 set = sound already generated
  `31` | chimney
  `34`..`39` | steel mill
  `3A`..`3B` | bank (temperate climate)
  `3C`..`3F` | food processing plant
  `40`..`47` | paper mill
  `48`..`58` | gold mine
  `4F` | wheel tower when not animated
  `58` | wheel tower when animated; animation state in m1 bits 5..0; m1 bit 6 set = sound already generated
  `59`..`5A` | bank (sub-arctic or sub-tropical climate)
  `5B`..`63` | diamond mine
  `64`..`73` | iron ore mine
  `74` | fruit plantation
  `75` | rubber plantation
  `76`..`77` | water supply
  `78` | water tower
  `79`..`7C` | factory (sub-tropical climate)
  `7D`..`80` | lumber mill
  `81`..`82` | candyfloss forest
  `82` | candyfloss 'trees' cut down
  `83`..`86` | sweet factory
  `87`..`88` | battery farm
  `88` | batteries 'reaped'
  `89` | cola wells
  `8A`..`8D` | toy shop
  `8E`..`93` | toy factory
  `8F` | animated part; animation state in m3 (valid range `00`..`31`) tile animation is started (m4 zeroed) on the periodic processing if field `2C` in the corresponding industry array entry is nonzero while the animation is in progress (see the array at `04328`) m4 holds the number of animation cycles that have already taken place; when this number reaches 8 the animation is stopped
  `94`..`9B` | plastic fountains (various stages of cyclic animation)
  `9C`..`9F` | fizzy drink factory
  `A0`..`A3` | bubble generator
  `A1` | generators
  `A2` | bubble capture facility; animation state in m3 (valid range `00`..`27`)
  `A4`..`A6` | toffee quarry
  `A5` | animated part; animation state in m3 (valid range `00`..`45`)
  `A7`..`AE` | sugar mine
  `AE` | animated part; animation state in m3 (valid range `00`..`5F`)

- m2: index into the array of industries
- m1 bit 7: clear = under construction
  - m1 bits 4..2: construction counter, for buildings under construction incremented on every periodic tile processing
- m1 bits 1..0: stage of construction (`3` = completed), incremented when the construction counter wraps around
  the meaning is different for some animated tiles which are never under construction (types `01`, `1E`..`20`, `30`, `58`; see above)

`9` m5 bits 7..4 clear: tunnel entrance/exit

- m5 bits 3..2: `0` - railway tunnel, `1` - road tunnel
- m5 bits 1..0 - direction: entrance towards: `0` = NE, `1` = SE, `2` = SW, `3` = NW
- m1: owner of the tunnel
- m3 bits 3..0 = track type for railway tunnel, must be 0 for road tunnel
- m4 bit 7 set = on snow or desert
- m4 bit 0 set = track with 'Track'number 0 is reserved by pbs
- m4 bit 1 set = track with 'Track'number 1 is reserved by pbs

m5 bit 7 set: bridge

- m5 bit 6 clear: bridge ending
  - m5 bit 5: clear - northern, set - southern ending
  - m3 bits 3..0 = type of track on the bridge, must be 0 for road bridge
  - m1: owner of the bridge
  m5 bit 6 set: bridge middle part
  - m5 bit 5 clear:
    - m5 bits 4..3: land under bridge: `0` - grass, snow or desert, `1` - water
    m5 bit 5 set:
    - m5 bits 4..3: transport route under bridge: `0` - railway, `1` - road
  - m3 bits 7..4 = type of track on the bridge, must be 0 for road bridge
  - m3 bits 3..0 = type of track under the bridge, if any
  - m2 bits 3..0: bridge piece (`0`..`5`)
  - m1: owner of the land under bridge
- m5 bits 2..1: `0` - railway bridge, `1` - road bridge
- m5 bit 0: clear - bridge in the X direction, set - bridge in the Y direction
- m2 bits 7..4: bridge type:

  Type | Max. speed (mph) | Description
  --- | --- | ---
  `0` | 20 | wooden
  `1` | 30 | concrete
  `2` | 40 | girder, steel
  `3` | 50 | suspension, concrete
  `4` | 60 | suspension, steel
  `5` | 70 | suspension, steel
  `6` | 100 | cantilever, steel
  `7` | 130 | cantilever, steel
  `8` | 150 | cantilever, steel
  `9` | 160 | girder, steel
  `A` | 200 | tubular, steel

- m4 bit 7 set = on snow or desert

`A`

- m5: tile type:

  `00` | transmitter
  `01` | lighthouse
  `02` | company statue
  `03` | company-owned land
  `80`..`93` | company headquarters (5 sets of 4 tiles each, updated quarterly depending on the company performance)

- m1: owner of the object (for lighthouses and transmitters normally `10`)

Classes `B` through `F` are reserved. The presence of a tile in one of the reserved classes will crash OTTD.

Original Copyright © 2003 by Marcin Grzegorczyk for TTDLX.
Transport Tycoon and Transport Tycoon Deluxe are Copyright © by Chris Sawyer. All the other trademarks are the property of their respective owners.