path: root/crawl-ref/docs/level-design.txt

How to make levels for Dungeon Crawl Stone Soup
===============================================

Contents:  A. Introduction
           B. Sample map
           C. Map symbols
           D. Header information
           E. Hints for level makers


A.   Introduction
-----------------

All fixed level information resides in various .des files to be found in 
the dat directory. If you are interested in adding some vaults, say, start
with the existing ones and modify them. Currently, the following .des files
are in use:

 splev.des:    * branch endings (like Elf:7, Vaults:8)
               * premade level maps (like the Ecumenical Temples and Geryon)
               * Pan lairs of named demons
               * branch entries (these can ornament the stairs for a branch)

 vaults.des:   * random vaults (Crawl sometimes chooses a special level 
                 when making up a new level; these are often challenging
                 and sometimes contain loot)
               * entry vaults (each game - except turorials - uses one of 
                 these premade maps for the vicinity of the entrance)
               * minivaults
               * Pan minivaults

 tricky.des:   * a few entry vaults which are harder in some regard 
                 (use of special items, or being puzzles)

 asciiart.des: * a few entry vaults which contain proper ASCII art.
                 These are a matter of taste - some find this annoying.


Kinds of Vaults
---------------
The different kinds of vaults used by Crawl are described briefly below.  In
most cases, when the dungeon builder places a vault on a level, the rest of the
level (assuming the vault is not a full-map vault) is generated as
rooms+corridors. The only exceptions to this are branch entry vaults and
minivaults, both of which are placed after the rest of the level is generated,
and therefore do not influence level generation.

* Entry vault:

A map designed for D:1, which (usually) contains the primary upstair { and is
always tagged "entry". A player starting a new game will usually land in an
entry vault.


* Branch entry vault, or branch portal vault:

A map containing the entry to a branch - either a branch stair (such as the
stair to the Orcish Mines), or a branch portal (a portal to Hell, say). Always
tagged "<branchname>_entry".


* Special level:

A map for a location of significance in the game, such as the Ecumenical
Temple, or the end of branches such as level 5 of the Snake Pit (Snake:5).
Special level maps usually have a PLACE: attribute.


* Random vaults:

Random vaults may be randomly generated at any level in the dungeon. Random
vault maps are selected by the dungeon builder based on their DEPTH:
attributes.


* Random minivaults:

Random minivaults are small maps that are placed onto a level that the dungeon
builder has already constructed fully otherwise (the level may include other
vaults).


B.   Sample Map
---------------

Before explaining the many technical details of the level syntax, we give 
a fictional temple entry so that you can the general map structure by way
of example. This is a _bad_ entry - do not recycle it!

First of all, each and every map consists of a name, a header and the actual
map itself (order is often not important but try to stick to this one). 

Note that lines starting with # are comments. The keywords are explained 
very briefly after the map and in detail in the following sections.

# name below:
NAME:    a_useless_temple_entry_02
# header section below:
ORIENT:  float
CHANCE:  5
TAGS:    temple_entry
FLAGS:   no_rotate
SHUFFLE: de
SUBST:   1=12.
MONS:    butterfly, plant
ITEM:    stone, w:10 any_good book / w:90 nothing
# actual map below:
MAP
xx1@2xx
x1wWw2x
ewwOwwd
x2www1x
xx1.1xx
ENDMAP

"ORIENT: float" tells the level builder that this entry can be anywhere on the
                level; other ORIENT: values can force a map to one edge of the
                level.
"CHANCE: 5" makes it appear less often (default is 10).
"TAGS: temple_entry" turns the 'O' on the map into stairs to the Temple.
"FLAGS: no_rotate" forbids rotation (but mirroring is still allowed).
"SHUFFLE: dw" may replace all 'd' with 'w' in the map.
"SUBST: 1=12." may replace each '1' with either '1' or '2' or '.'.
"MONS: butterfly, plant" turns all '1' into butterflies, and '2' into plants.
"ITEM: stone" turns all 'd' into stones
"ITEM: w:10 any book / w:100 nothing" turns all 'e' into a book
       (with 10% chance) or creates no object (with 90% chance).
       
The symbols on the map:
 x - rock wall       
 w - water (could be deep or shallow)
 W - shallow water
 . - plain floor
 @ - entry point (this square will be connected to the rest of the map)
 O - stairs to the Temple
 1 - first monster from the list (here butterfly) - note the SUBST: 1=12.
 2 - second monster from the list (plant)
 d - first item from the list (here stones)
 e - second item from the list (here occassionally a book)
 
 
D.   Map symbols
----------------

Terrain
-------
 x - rock wall                                            (DNGN_ROCK_WALL)
 X - permanent rock wall  - always undiggable        (DNGN_PERMAROCK_WALL)
 c - stone wall - only affected by Shatter               (DNGN_STONE_WALL)
 v - metal wall - grounds electricity                    (DNGN_METAL_WALL)
 b - crystal wall - reflects cold and fire       (DNGN_GREEN_CRYSTAL_WALL)
 a - wax wall - can melt                                   (DNGN_WAX_WALL)

 . - floor                                                    (DNGN_FLOOR)
 + - closed door                                        (DNGN_CLOSED_DOOR)
 = - secret door                                        (DNGN_SECRET_DOOR)

 W - shallow water
 w - deep water - can be turned into shallow water; prevent this with the
     no_pool_fixup TAG. Also, this may receive water creatures! For entry
     vaults, avoid this with the no_monster_gen TAG.
 l - lava - again, use the no_monster_gen TAG for entry vaults!

Features
--------
 @ - entry point - must be on outside and, except in ORIENT:float layouts,
     must always be on a particular side or sides - see templates. If you use
     ORIENT: float, and do not use any @, the dungeon builder will connect at
     least one floorspace on the edge of your map to the rest of the level; if
     there is no floorspace on the edge of your map, it will be isolated.
 }{ - stairs 82/86 - You must be able to reach these from each other. The 
      { upstair is also the stair on which the player will enter the 
      dungeon for entry vaults.
 )( - stairs 83/87
 ][ - stairs 84/88

 >< - extra rock stairs - you can leave level by these but will rarely be 
      placed on them from another level

 I - orcish idol (does nothing)

 ^ - random trap.
 ~ - random trap suitable for the branch and depth the map is being used.

 A - Vestibule gateway (opened by Horn). 
 B - Altar. These are assigned specific types (eg of Zin etc) in dungeon.cc,
     in order.
 C - Random Altar.

 F - Usually a Granite Statue, but may be Orange or Silver or Ice (1 in 100) 
 G - Granite statue (does nothing) - you can see through but not walk through
 H - orange crystal statue (attacks mind)
 S - Silver statue (summons demons). Avoid using (rare).

 T - Water fountain
 U - Magic fountain
 V - Permanently dry fountain

# Note: Due to the level maker having seen incremental improvements over the
# years, there are some inconsistencies. For examples, dangerous statues
# (orange, silver ice) are now genuine monsters. In particular, the 'G' and 'S'
# glyphs could be dispensed with (but many older vaults use them, of course) -
# especially as there's no glyph for ice statues.
#
# Also, the most of the other feature glyphs can be replaced with KFEAT:
# lines. The same goes for some item glyphs ('O', 'P', 'R', 'Z') which could
# be replaced by KITEM: lines.

Items
----- 
 $ - gold
 % - normal item
 * - higher level item (good)
 | - acquirement-level item (almost guaranteed excellent)
 O - place an appropriate rune here. For portal vaults, place the portal here.
 P - maybe place a rune here (50%)
 R - honeycomb (2/3) or royal jelly (1/3)
 Z - the Orb of Zot
 d-k - item array item. See section below on ITEM: arrays for more info.

Monsters
--------
 0 - normal monster
 9 - +5 depth monster
 8 - (+2) * 2 depth monster (aargh!). Can get golden dragons and titans
     this way.
 1-7 - monster array monster. See section below on MONS: arrays for more 
     information


D.   Header information
-----------------------

NAME:    a_string
         Each map must have a unique name. Underscores and digits are ok.

ORIENT:  (float |encompass | north | northwest | ... | southeast)
         
         Some kind of ORIENT: line is mandatory, unless you want the vault to 
         be a minivault, which is usually not what you want. Valid values are:
         * "float": The dungeon builder puts your vault wherever it wants to.
         * "some_direction": The vault lies along that side of the map:
           xxxxxxxxxx       xxxxxxxxxxxxx
           xORIENT:Nx       xORIENT:NW|..
           x.VAULT..x       x.VAULT...|..
           x--------x       x---------|..
           xrest....x       xrest........
           x...of...x       x.....of.....
           x...levelx       x.......level
           ...which brings us to padding. With any some_direction orientation, 
           you need 6 layers of x-padding along any level-edge that the vault 
           borders. For instance, if your map is ORIENT: north, you must have a 
           6 deep border of rock wall (or any other kind of wall) along the 
           northern, eastern, and western edges of the map.
         * "encompass": the vault completely occupies the entire level. 
           Padding is needed on all 4 sides.

DEPTH:   For random vaults and minivaults, this gives the range where the vault
         may be placed in the main dungeon. E.g.
           DEPTH: 7-20           
           
CHANCE:  (number with 10 being default)
         For entry vaults and any other vaults randomly picked from among 
         a set, this type of line affects the likelihood of the given vault
         being picked in a given game. The default CHANCE: is 10. The 
         likelihood of a vault getting picked is:
         [vault's CHANCE: / sum of all CHANCE:s of vaults of that type]

PLACE:   Used to specify certain special levels. Existing special levels are:
         Temple, Hell, Dis:7, Geh:7, Coc:7, Tar:7, Hive:4, Vault:8, Snake:5, 
         Elf:7, Slime:6, Blade, Zot:5, Tomb:1, Tomb:2, Tomb:3, Swamp:5.

         PLACE can also be used to specify arbitrary places, like D:3, which
         will force the map (or one of the maps with PLACE: D:3) to be picked
         when D:3 is generated.

         PLACE cannot be used to specify places in the Abyss, Pandemonium,
         or Labyrinths.

         PLACE can be used with random vaults and minivaults for testing them.
         
TAGS:    generate_awake, no_item_gen, no_monster_gen, no_pool_fixup, orc_entry
         Tags go an a TAGS: line and are space-separated. Valid tags are:
         * "entry": this tag MUST be there for a vault to be pickable as 
           an entry vault.
         * "generate_awake": Monsters placed (using MONS, KMONS) in this 
           vault will be generated awake.
         * "no_item_gen":   Prevents random item generation in the vault. 
           Items explicitly placed by the vault are not affected.
         * "no_monster_gen": Prevents random monster generation at the time
           of the vault's creation. Highly advised for entry vaults with
           a player-hostile geography, MUST-HAVE for those with water/lava.
         * "no_pool_fixup": prevents water squares next to land from being 
           randomly converted from deep water (the default) to shallow.
         * "branch_entry" eg. "orc_entry", "lair_entry" etc. Currently used:
             temple_entry, orc_entry, vault_entry, lair_entry, hive_entry.
           If chosen, these maps will contain the stairs for that branch. 
           Use "O" to place the stairs. Branch entries should go to splev.des.
           As long as a branch has very few entries, a dummy one is a must.
         * "mnoleg" or the name of some other pandemonium lord. This makes
           the map eligible for said pan lord's lair (and it can't appear
           anywhere else).

FLAGS:   no_rotate, no_hmirror, no_vmirror
         Flags go on a FLAGS: line and are space-separated. Valid flags are:
         * "no_rotate":  Normally, the dungeon builder can, at its whim, 
           rotate your vault. This flag tells it, "hey, don't do that to my
           vault!"
         * "no_hmirror": Like no_rotate, but for horizontal mirroring.
         * "no_vmirror": Like no_rotate, but for vertical mirroring.

ITEM:    (list of items, separated by comma)
         These are used to help place specified items at specific places 
         within a vault. They create an array with up to 8 positions. What's
         in the first position in the array will be used when the dungeon 
         builder sees a "d" in the vault definition, the second will be used 
         for "e"s, etc. Positions are comma-separated; several ITEM: lines 
         are possible as well. The following defines letters 'd' - 'g':
           ITEM: stone, ring mail, meat ration, ring of hunger
           
         Positions can contain multiple possibilities, one of which the 
         builder will choose randomly. Separate such multiple possibilities 
         using a slash. Note that "nothing" (without the quotes) is a valid 
         possibility. The random choice is done for each individual occurence 
         of the letter. You can also give possibilities a "weight," which 
         affects their chance of being picked. The default weight is 10. You
         can abbreviate "weight:30" by "w:30". The chance to pick a 
         possibility is
         [possibility's weight: / sum of all weight:s in that array position]
         For example, the following line makes letter 'd' into a bread ration
         with 50% chance, or apple or orange with 25% chance each:
           ITEM: bread ration / w:5 apple / w:5 orange

         Modifiers: 
         * "good_item" makes the builder try to make the item a good one.
         * "any" by itself gives random choice; you can combine "any" with 
           "good_item."
         * "any book", "any misc" etc. gives a random item of that class.

         Limitations: You can't affect stack quantity for stackable items, 
         nor can you affect curse status nor item race, nor can you give 
         specific egos, nor can give fixedarts. You also can't lay down 
         corpses, skeletons, or chunks.
 
MONS:    (list of monsters)
         These are used to help place specific monsters at specific places 
         in a vault. They create an array with up to 7 positions. What's in 
         the first position in the array will be used when the dungeon 
         builder sees a "1" in the vault definition, the second for "2," 
         etc. Note that if, for example, you place a 3 on the map, but your
         MONS: line has no third position, the 3 will be filled with 
         RANDOM_MONSTER.
         You can use weights as for ITEM: lines.

         Individual monsters may be prefixed with the "generate_awake" 
         (without the quotes). Use this sparingly.
         Note that 8, 9, 0 also place monsters (see the table).
 

SHUFFLE: def, 12/3?
         This allows you to randomly permute glyphs on the map. There are 
         two ways:

         SHUFFLE: 123w     (i.e. list of glyphs, NOT slash-separated)
         could, for example, swap all occurences of "1" with "2", as well as
         swapping all "3" with "w" (or any other of the 24 possibilities).

         SHUFFLE: 12/3w    (i.e. list of slash-separated blocks of same size)
         will either do nothing or swap all "1" with "3" and then also swap 
         "2" with "w" everywhere.

         Several SHUFFLE: lines can be used, and mixed with SUBST:, and the
         shuffles and substitutions will be applied in order. You can also 
         put multiple SHUFFLEs on one line, comma-separated. Shuffles cannot 
         use , or /. All spaces are stripped before shuffling.
  
SUBST:   ?=xc, !:bv, 1=2 1:100
         The SUBST: directive allows you to specify a placeholder symbol 
         that is replaced with a random glyph from a set. For instance:

         SUBST: ? = TUV
         replaces occurrences of ? with one of TUV. Since whitespaces are
         irrelevant, this is the same as
         SUBST: ? = T U V   

         SUBST:  ? = T:20 U V
         makes T twice as likely to be used as U or V (the default weight
         is 10). Note that there has to be at least one space before and 
         after T:20 and that whitespace in T:20 is not permitted.

         SUBST:  ? : TUV
         replaces occurrences of ? with one of TUV, and guarantees that all
         occurrences of ? will get the same replacement symbol.

         The placeholder and replacement symbols can be any non-space, 
         printable character, including : and =, apart from commas. For 
         example, the following is valid:
         SUBST: = = +=:123def" 

         SUBST: lines can safely replace symbols with themselves, as in:
         SUBST: w = wW

         Multiple SUBST: lines can be used, and mixed with SHUFFLE:, and 
         will be applied in order. Multiple substitutions can be performed
         on one line, using commas.

KFEAT:   Z = C / needle trap / antique armour shop / altar of Zin
         The KFEAT: directive allows you to specify a placeholder symbol 
         that is replaced with another symbol, named feature, trap, or 
         shop. For example, the line above will replace occurrences of Z 
         with C (random altar), a needle trap, an antique armour shop, or
         an altar of Zin. Different instances of Z may receive different 
         replacements. To force a single replacement for all Z,  use:
         KFEAT: Z : C / needle trap / antique armour shop
         You'll notice that 'Z' is the symbol of the Orb of Zot. Kxxx 
         directives allow you to assign arbitrary definitions to any symbol.

         If you want no feature as an option in a KFEAT line, use 'floor'.
         If you do not want to specify the type of shop, use 'any shop' or
         'random shop'.

         The placeholder used by KFEAT can be shared by KITEM and KMONS;
         see below. If the placeholder is shared, all defined Kxxxx 
         operations for the placeholder are performed. Also, all Kxxx 
         lines accept weights as for MONS or ITEM.

KMONS:   ? = orc priest / w:3 deep elf priest
         KMONS: allows you to specify a placeholder symbol that indicates 
         the position of a monster (or monsters).
         Using KMONS: allows you to exceed the 7 slot limit for monsters. 
         It is also useful if you want to place a monster on a non-floor 
         square (used in association with a KFEAT:). Fr example,
         KFEAT: Z = W
         KMONS: Z = rat
         places a rat on a shallow water square for all occurrences of Z.

KITEM:   ? = potion of healing / potion of restore abilities
         KITEM: places the specified item at all occurrences of the 
         placeholder. It can be combined with KFEAT: and KMONS: lines for
         the same placeholder.

         For items like gold or fountains, you have to use the description 
         of items instead of their shortcuts. For example,
         KITEM: none / gold
         works but the following does not: 
         KITEM: none / $

E.    Hints for level makers
----------------------------

* Technical stuff:
  If your map is not a minivault or a floating vault, make sure the 
  side(s) forming the border have a rock wall padding at least 6 deep. For
  instance, if your map is ORIENT: north, you must have a 6 deep border of 
  rock wall (or any other kind of wall) along the northern, eastern, and 
  western edges of the map. If you're doing a fullscreen map (encompass), 
  you must pad all around the map with 6 layers of wall.

  You do not have to place all of the stairs unless the level is full 
  screen, in which case you must place all except the extra stairs (> and
  <). The <> stairs can be put anywhere and in any quantities but do not 
  have to be there. Any of the other stairs which are not present in the 
  vault will be randomly placed outside it. Also generally try to avoid 
  rooms with no exit (use at least > or < to make it possible for players
  to get away).

  The entry point '@' must be present (except full-screen vaults where it 
  must not). For ORIENT: float maps, all @ will be connected to floors in
  the rest of the map. Make sure that no part of your entry level can be
  cut off! If no @ is present, the level builder will put one on a random
  floor space '.' at the circumference. (Sometimes this may be used for
  good effect. When you give no @'s with this feature in mind, please make
  a comment stating this - else somebody may just add @'s later on :)
  
  Note that non-rectangular maps will be padded with rock walls for the
  smallest rectangle containing them. Unfortunately.

  Entry levels should be rather small. Their intention is to provide some
  atmosphere for the starting room, not to get a grip on the whole of D:1.
  Minivaults should be rather small, as well, in order to increase the
  chances they may actually be chosen during level generation.
  
* Randomise!
  The level making syntax is now very supportive for making a single map
  appear in many versions. Use the SHUFFLE: and SUBST: directives and look
  at the existing entry vaults. Besides reducing tedium, this avoids giving
  veterans a spoiled edge. For example, if a secret chamber with loot is
  always at the same place, it's a no-brainer for those who know. The same
  goes for traps. This is much less so if there are several places for the
  chamber (or trap) and there's even a chance it doesn't exist.
  
  You can also use CHANCE to create modified versions of the same map. In
  order to do this, make several maps and endow each with a chance such 
  that the sum of chances add up to 10.

  Randomisation does not just apply to layout: you could also have 
  different monster population sets (for example make a branch end skewed
  for either melee or ranged opponents), or perhaps couple difficulty to 
  loot.

* Not too much loot.
  For example, entry vaults should in general have very little loot - in 
  particular no good_xxx or '*' items lest they might give incentive for
  start-scumming. For random vaults, there needn't be loot at all and, in
  any case, there shouldn't be too much of it. Compare with the branch ends
  rich in treasure (Tomb:3, Cocytus etc.) to get a feeling for this.

* Have a theme.
  It is often worthwhile (to me at least) to have a theme in mind before
  making the actual level. For entry vaults, something simple like
  'fortress' or  'forest' may be enough. For later (or larger) maps, try 
  to think of distinguishing features your map may have. Being cool can 
  be good enough, but possessing some gameplay value (for example by being
  easier for particular skills/capabilities like ranged attacks or 
  necromancy or Traps & Doors) is even better.
  
* Testing your maps.
  This is easy for entry vaults. Temporarily introducing a CHANCE: 5000
  will make your entry appear almost always. For other vaults, you can
  for the moment declare them as entry vaults with a huge CHANCE: as 
  above (and preferably in wizard mode). For more intricate things like
  new branch ends, you have to resort to wizard mode and use the &~ command
  to go directly to the place where the map is used, say Snake:5. You may want
  to use a high CHANCE: again, if the map has alternatives (like Snake:5, or
  Coc:7).

  If the .des file syntax is incorrect, Crawl will tell you on which line of 
  which des file it found the syntax error, making for easier debugging.

* Be fair!
  Crawl is hard but try to balance your monsters. While it is true that Orc:1
  can show an orcish knight, this is very rare. Hence it's probably a bad idea
  to use orcish knights for an entry to the Orcish Mines. 

  Phrased more generally, do not use OOD (out-of-depth) monsters unless you
  really know what you want. 

  Be especially fair when creating entry vaults. If your entry is too
  hard, it might get degraded to tricky.des (or just removed). Keep in
  mind that your vault will be played very very often, so even small
  chances of something stupid happening (like creation of a really nasty
  monster) will kick in often enough.
  
* Minivaults vs random vaults.
  Minivaults are handled very differently from regular vaults and special
  levels. They're placed *after* normal map generation, whereas normal 
  vaults are placed before generating the rest of the level. There's no 
  way to guarantee generation of a minivault on a particular level, although
  using a PLACE: attribute makes the dungeon builder try very hard to place
  the minivault on the specified level. Regular vaults can always be forced to
  appear using a PLACE: attribute.

  Technically, you make a minivault like a normal floating vault but 
  without an ORIENT: line. Note that minivaults used to be exclusively of
  size 12x12 but this restriction is gone. Still, the smaller the better.
  
* levdes.vim.
  Your choice of editor can greatly affect your level building. While vi's
  reputation may be close to Crawl's when it comes to fiendishness, there 
  is a style file (levdes.vim in the dat directory) which helps tremendously
  (it colours the various glyphs on the maps, and it highlights the syntax).
  Even Windows users can profit from this by using gvim, a freeware vim
  clone with a graphical user interface which knows shortcuts like Ctrl-X
  etc.