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Revision as of 14:24, 5 November 2006 by Eleazar (talk | contribs) (desert)


Terrain system

The goal is to convert the old single letter terrain system to a new multi letter system. The internal changes to the engine are almost done.

These are the proposals and explanations for the new system, once these are final and implanted these texts will move into the wiki.

Version: proposal 2.0
Last updated: --SkeletonCrew 11:43, 5 November 2006 (CET)

proposal 1.1

  • added the encounter terrains

proposal 1.2

  • added the link to the new proposals of Mog and Eleazar

proposal 1.3

  • added reminder to add fog/shroud to the editor
  • added idea to maybe add support to add tiles at the top and left

proposal 2.0

  • removed editor changes from proposal and moved to own topic
  • removed the discussion points and wrote the conclusion
  • rewrote User:SkeletonCrew#terrain_strings
  • rewrote the letter proposal, with the input given so far


Every terrain type gets a new field named string this will be the new string to use to refer to the terrain. The old char field will stay for the existing terrains, this is needed to convert older maps to be used with the new engine.

This string will exist of 2 to 4 characters, the allowed characters are all letters (the engine is case sensitive), all numbers and the symbols / | \. Note leading numbers are not allowed in the string, they might give confusion with starting locations. Other characters are reserved for special uses in the engine.

The limit of 4 characters is not the upper limit of the engine, but the upper level for easy parsing. The internal format uses 4 bytes and every character is 1 byte. This way it's very easy to convert the characters to the internal format. If more letters are required it will require some modifications to the engine.

I'm considering to allow 1 character terrains as well since I've some trouble to find a second letter everywhere.

Every terrain will also get a new field named theme this is explained in the editor section.

scenario map

The map will use the new strings instead of the old letters. For every tile a string will be used instead of one letter, these strings are separated with a comma. Between the string and the comma one or more spaces are allowed.

Instead of spaces tabs are allowed, but keep in mind what looks good in your text editor, might look horrible in the editor of somebody else. The official files should use spaces.

The WML for map will use the same format. The letter for map WML will use a single terrain string without comma's.


The need two modifications the map format and the type format.


This format will change a bit more than the other items. The old format is described here TerrainGraphicsWML. According to mog the letters in the map are never used, only the anchors are used. The new format will only accept anchors. The special characters . and * will stay the same.

This map file will no longer be space separated but comma separatedand. Odd lines will start with a leading comma instead of 2 spaces. Spaces are allowed for padding

Also here tabs are allowed instead of spaces, see previous section.

For example this

1   1
1   1

will become



, 1
1 , 1
, 2
1 , 1
, 1"


The type will be a list of terrains, comma separated. Spaces are allowed but then the items need to be between brackets. (A WML rule.) Also after special modifiers a comma is required (at the moment only the ! is a special modifier, but that might change in the future.)

Mog had an idea which will also be implanted, the * can be used in a terrain string, V* would match all terrain strings starting with the letter 'V'. Vh* would match all terrain strings starting with 'Vh' eg Vh, Vha, Vhaa but not VH or vH.

terrain files

Eleazar would like to move the terrains in subfolders, this seems to be possible with the current system. The required modifications can be found in the following changelog

I've no idea what the best possible directory layout will be. I'll ask Eleazar to do this change when I'm ready for it. At the moment I've some patches in my queue which will conflict with these changes.

terrain strings

The terrain strings will consist of 2 till 4 letters which indicate the terrain. Numbers are not allowed except for starting positions. These are allowed to be between 1 and 4 characters. (Note Wesnoth only supports 9 starting positions.) The following special characters can be used /|\ these should be used for directional terrains, which are only bridges at the moment.

The terrain letter _ is reserved for interal special terrains this will alway be used as leading character and not used inside strings.

For readability terrains should start with a capital letter followed by one or more lowercase letters (with a maximum of 3 lower case letters). The official terrains must follow these rules, the custom terrains should follow these rules.

There will be some letters reserved for user made content these letters are Y, y, Z, z. This means every terrain with one or more of these letters inside are custom terrains. This way it's easier to integrate a new terrain without having to change the terrain-graphics.cfg.

Since UTBS is mainline the custom terrain used there will be moved to the new system.


The aliases will also be a comma separated list, where the same discussion about the + and - can be started as in the types.

terrains sorted per group

This list shows the new proposal for the terrains, which takes in account the idea's of Mog and Eleazar. The italic strings are reservations for terrains. The only terrain which isn't backwards compatible is '*'. The other terrains will be converted.

Some letter defined in the old system don't have a terrain defined yet. These are still listed with their reserved letter. Just in case the terrain gets defined before this system is up and running.

I think about merging some theme's if the number of items is to small. The following merges will probably be done

  • hill, mountain
  • water, swamp
  • castle, keep

I still want to keep the themes, if for example the number mountain and hill terrains increases enough to justify their own page the splitting will be trivial.

The letters "$.;:<>_` are listed but unassigned in the old list and thus not supported in the new system.

Snow terrains

String Old letter Description Theme
Ai i ice snow
Aa S tundra "Arctic" snow


Since bridges are directional all strings here will be appended with either /|\ to show their direction. In this list these signs are replaced with a *.

String Old letter Description Theme
Bx* Bridge chasm for aboveground bridge
Bxu* Bridge over chasm underground bridge
Bsw* wooden bridge over swamp NOTE bws Brigde wood swamp bridge
Bws* Stone Bridge over shallow water NOTE bss Bridge stone swamp not better? bridge
Bww* /|\ wooden bridge bridge, over wadeable, wooden NOTE Brigde wood or Bridge wood water not better? bridge, common


String Old letter Description Theme
Ce n encampment (castle) castle, common
Ch C human castle castle, common
Chr N ruined castle castle
Chs q human ruin (swamp) castle
Chw Q human sunken ruin castle
Co O will be an Orc Castle one day castle
Cud o dwarven castle "castle underground, dwarf" castle, underground


NOTE still need to add the UTBS terrains

String Old letter Description Theme
Dd I desert desert
Do P desert oasis desert
Ds d sand, (old desert) desert


String Old letter Description Theme
Fa F forest (snow) "forest arctic" forrest, snow
Fb Sinister Forest "Forest, Bad" forrest
Fet ? great Elven tree forrest
Ff f forrest forrest, common
Ft T forrest tropical forrest


String Old letter Description Theme
Gb dying "Grass brown/bad" grass
Gf Farmer's Fields grass
Gg g grass grass, common
Gs G savanna (grass) grass


String Old letter Description Theme
Ha H hills (snow) "hills arctic" hill, snow
Hd J desert hills (dunes) hill, desert
Hh h hills hill, common


String Old letter Description Theme
Kk K keep (castle) keep, common


String Old letter Description Theme
Ma j snowy mountains mountain, snow
Md M desert mountains mountain, desert
Mm m mountain mountain, common

(mostly) Impassable

String Old letter Description Theme
Qx X chasm for above ground misc
Qxu chasm for underground misc, underground
Qxw chasm with water pouring over the edge misc
Ql l lava misc
Qsq stone wall misc


String Old letter Description Theme
Rc Carpeted Floor road
Rd E desert road road, desert
Rr r dirt road road, common
Rs stone road road
Rw Wood floor (interior) road


String Old letter Description Theme
Sb fetid swamp "Swamp Bad" swamp
Ss w swamp swamp


String Old letter Description Theme
Uf ] mushroom grove "underground forest" underground
Uh [ rockbound cave (functionally "underground hill") underground
Uu u normal cave underground
Uuc normal cave, carved underground
Uui ' illuminated cave underground


String Old letter Description Theme
Vda B desert village (adobe) village, desert
Vdt U desert village (test) village, desert
Veg t elven village "village elven grassland" village
Ves e elven (snow) village village, snow
Vha V village, snow snow village (tundra, village) village, snow
Vhg v human village (village) village, common
Vhh a human hill village village, hill, common
Vhhs A human (snow) hill village NOTE not Vhha??? village, snow, hill
Vhm b human mountain village village, mountain
Vht L tropical village (savanna, village) --nothing foresty about this village village
Vu D underground village (cave, village) village, underground
Vud p dwarven village village, underground
Vwm Z mermen village (shallow water) village, water
Vws Y swamp village (swamp, village) village, swamp


String Old letter Description Theme
Wo s deep water "water, ocean" water, common
Ww c shallow water, "water, wade-able" water, common
Wwf k river ford "water wadeable, ford" water
Wwu shallow underground water water, underground


String Old letter Description Theme
Xm & impassable moutains impassable, mountain
Xsw Impassable stone wall (interior) impassable
Xu W cavewall impassable, underground
Xuc cavewall, carved impassable, underground
Xww Impassable wooden wall (interior) impassable


These terrains are hardcoded in the game and translated automatically. The old UMC terrains are here for backwards compability this compability will only be guaranteed till the next major release after 1.2.(That would be 1.4 or 2.0.) As stated before the * will no longer be supported.

String Old letter Description Theme
_f ~ fog misc
_s (space character) void/shroud misc
_za ^ reserved for UMC misc
_zb % reserved for UMC misc
_zc @ reserved for UMC misc
_zx x reserved for UMC misc
_zy y reserved for UMC misc
_zz z reserved for UMC misc

encounter terrains

This list maintains the encountered terrains by the user this list is used in the help function to decide what to show and what not. This is now a comma seperated list. The new version will also be a comma separated list but with the new terrain strings instead of letters. In order to keep it backwards compatible at startup the system will check for encountered_terrains and encountered_terrains13 . Then test the following conditions is this order:

  • if encountered_terrains13 is found these are loaded.
  • if encountered_terrains is found, these are converted to encountered_terrains13 format and loaded
  • none are found, nothing will be done.

When writing only encountered_terrains13 will be used.

The reason to keep it backwards compatible is that if somebody tries an 1.3.x version and doesn't like it, it's no problem to return to 1.2.x. If we convert encountered_terrains to the new format it might give troubles when loading it with 1.2.x.


The editor also will need an overhaul due to the changes, since the terrain consists of a maximum of 4 characters I propose it writes the terrain as a string of 6 characters; the terrains string followed by a comma and padded with spaces. eg the following terrain string


will be written as

123456123456123456123456123456 (numbers won't be written.)
Vh,   Vha,  Vhaa, Vha,  Vh 

Discussion: Should the editor be able to write the old format terrain or not.

custom terrains

Zookeeper told me there's no option to add custom terrains at the moment. I want to add a button to add a custom terrain, once clicked it will prompt for the terrain string and insert the tile to the list of available tiles and allow to use this tile. The tile will be 'painted' with the terrain string. When loading a map with unknown strings these will be added to the list of terrains. The only problem will be the location of the terrains but I'll worry about that later.

There should also be an option to add fog/shroud tiles to the map. See

Discussion: Would this solve the unkown tile problem?


In my opinion the list with terrains to browse is pretty long and this will only grow in the future. I want to add an extra grid of buttons with theme's the buttons will have an icon for their theme. When a button is clicked the list of terrains is filtered per theme. eg when the theme villages is selected only village tiles are shown. Every terrain gets one or more themes for example a snow forest can be in the theme forest and the theme snow, so with either theme this tile is shown. There will be 2 special theme's favorites and map. Favorites are your favorite tiles saved in preferences and can contain unknown terrains. Map are all tiles already used on this map, including the unknown.

Discussion: Is this handy?

resize map

maybe there should be an option to add tiles to the left and top instead of only to the right and bottom. See

Small maps

It would be handy to be able to create maps smaller than 20 x 20 for WML usage. IMO as soon as the map goes below this threshold a warning should be shown, that the map might nog work properly as main scenario map. See


Thing I plan to do after I finished my WIP's.

team sides

After the terrain system has been modified it's possible to define more teams, EdB asked this in irc at 20061027.

It would be nice to support 12 sides in multiplayer with their own tcolour. The engine should support more sides for the AI to use. These will use and scenario WML defined colour. It's not sure whether WML supports this if not the support should be made. EdB will look for an possible algo to define nice auto colours.

terrain archtypes

Eleazar had an idea for terrain archtypes in the terrain thread. It looks sane and would be nice to implant.


Various things I want to look at at some time.

  • version checks for WML, needed or not?
  • modulo WML, needed or not?
  • continue to work on the Python AI