Content
Note
If you are looking for specific tileset information or style guides, try the tileset repository:
A package of images for the game.
A single image that represents either an individual game entity or a common background
File name without an extension.
A unit square in the game world with certain coordinates, where entities can exist and on which sprites are drawn. Sometimes used (incorrectly) in place of "sprite".
A collection of sprites with identical sizes and offsets composited into one image file that the game will read.
Machine-readable description mapping the contents of tilesheets to game entities.
A collection of tileset metadata.
JSON configuration object that describes which sprites are used for which game entities and how.
A tileset that is stored as directories of individual sprites and tile entries.
Converts a compositing tileset into package suitable for the game: a set of tilesheets and the tile_config.json.
Compositing tileset subdirectory containing sprites and tile entries.
Describes tilesheet directories for compose.py
{ // The simplest version
"id": "mon_cat", // a game entity ID
"fg": "mon_cat_black", // a sprite root name that will be put on foreground
"bg": "shadow_bg_1" // another sprite root name that will be the background; can be empty for no background
}Sprites can be referenced across tilesheet directories, but they must be stored in a tilesheet directory with their size and offset.
id can be an array of multiple game entity IDs sharing the same sprite configuration, like "id": ["vp_door", "vp_hddoor"]. id game values that are used as-is include terrain, furniture, items (except corpses), monsters, fields, traps.
The special ID unknown provides a sprite that is displayed when an entity has no other sprite. Other hardcoded IDs also exist, and most of them are referenced in src/cata_tiles.cpp. A full list of hardcoded IDs may be present in tools/json_tools/generate_overlay_ids.py stored as CPP_IDS but it's updated manually and may lag behind. Other IDs may be found below.
Running trail animations (game.cpp):
run_nw Player running towards north-west.
run_n
run_ne
run_w
run_e
run_sw
run_s
run_se
Bashing animations (handle_action.cpp):
bash_complete Bash results in destruction of target.
bash_effective Bash effective but target not yet destroyed.
bash_ineffective Bash not effective.
Shadows (cata_tiles.cpp):
shadow Drawn when creature present in tiles above.
Special prefixes that are used include:
overlay_effect_ for effects.
overlay_mutation_ and overlay_mutation_active_ for both mutations and bionics.
overlay_worn_ and overlay_wielded_ for items being worn or wielded by characters.
corpse_ for corpses.
overlay_ for movement modes.
vp_ for vehicle parts (see also symbols and standard_symbols JSON keys that are used as suffixes).
explosion_ for spell explosion effects. Multitile is required; only supports "center", "edge" and "corner".
Special suffixes that are used include:
_intx for fields with a specific intensity level where x is the intensity level. Intensity counts from 1 and there are usually three levels so: _int1 _int2 _int3
Are defined by adding _female or _male part to the overlay_ part of a prefix before other parts: overlay_female_ or overlay_male_, overlay_female_worn_, overlay_male_worn_.
Are defined by adding _season_spring, _season_summer, _season_autumn, or _season_winter suffix to any tile entry id. For example "id": "mon_wolf_season_winter".
Defined by adding _transparent suffix to any tile entry id. For example "id": "t_wall_transparent". The transparent version is used to prevent occlusion by high tiles, especially in ISO tilesets.
Are defined by adding _var_variant_id, where variant_id is replaced by the id of the variant you want to sprite.
e.g. for an item with the id item1, with variants orange and pear, to specify a tile for the item, simply use item1. For the variants, use item1_var_orange and item1_var_pear.
You can add "rotates": true to allow sprites to be rotated by the game automatically. Alternatively, fg and bg can be an array of 2 or 4 pre-rotated variants, like "fg": ["mon_dog_left", "mon_dog_right"] or "bg": ["t_wall_n", "t_wall_e", "t_wall_s", "t_wall_w"].
fg and bg can also be an array of objects of weighted, randomly chosen options, any of which can also be an array of rotations:
"fg": [
{ "weight": 50, "sprite": "t_dirt_brown"}, // appears approximately 50 times in 53 tiles
{ "weight": 1, "sprite": "t_dirt_black_specks"}, // appears 1 time in 53 tiles
{ "weight": 1, "sprite": "t_dirt_specks_gray"},
{ "weight": 1, "sprite": "t_patchy_grass"} // file names are arbitrary, but see `--use-all` option
],"multitile": true signifies that there is an additional_tiles object (redundant? probably) with one or more objects that define sprites for game entities associated with this tile, such as broken versions of an item, or wall connections. Each object in the array has an id field, as above, and an fg field, which can be a single root name, an array of root names, or an array of objects as above. "rotates": true is implied with it and can be omitted.
For terrain or furniture that is intended to auto-connect using multitiles, set the properties connect_groups and connects_to in the object definition (not in the tileset!) to an appropriate group:
{
"type": "terrain",
"id": "t_brick_wall",
...
"connect_groups": "WALL",
"connects_to": "WALL",
...
}For both properties, arrays of multiple groups are possible.
connect_groups adds the type to one or more groups, while connects_to makes the type connect to the given group(s).
Connections are only set up from types that have a connects_to group to types that have the same group in connect_groups.
For details, see JSON_INFO.md, sections connect_groups and connects_to.
Wall work out of the box without modifying terrain definitions, as the required group WALL is implied by the flags WALL and CONNECT_WITH_WALL for connect_groups as well as connects_to (i.e. symmetric relation).
For available connect groups, see JSON_INFO.md, section Connection groups.
For the full multitile, the 16 sprite variants of this template are required:
In JSON, the multitile would be defined like this:
{
...
"multitile": true,
"additional_tiles": [
{
"id": "center",
"fg": "t_wall_w_center"
},
{
"id": "corner",
"fg": [
"t_wall_w_corner_nw", "t_wall_w_corner_sw",
"t_wall_w_corner_se", "t_wall_w_corner_ne"
]
},
{
"id": "t_connection",
"fg": [
"t_wall_w_t_connection_n", "t_wall_w_t_connection_w",
"t_wall_w_t_connection_s", "t_wall_w_t_connection_e"
]
},
{
"id": "edge",
"fg": [ "t_wall_w_edge_ns", "t_wall_w_edge_ew" ]
},
{
"id": "end_piece",
"fg": [
"t_wall_w_end_piece_n", "t_wall_w_end_piece_w",
"t_wall_w_end_piece_s", "t_wall_w_end_piece_e"
]
},
{
"id": "unconnected",
"fg": [
"t_wall_w_unconnected", "t_wall_w_unconnected"
]
}
]
}Terrain and furniture can auto-rotate depending on other surrounding terrain or furniture using rotates_to.
For details, see JSON_INFO.md, sections connect_groups and rotates_to.
Usage examples for terrain are doors and windows that look differently, seen from inside and outside (e.g. curtain).
An example for furniture are street lights that orient towards the pavement.
The mechanism works like to connects_to, and can be combined with it.
It also makes use of the same Connection group, given by property connect_groups.
Currently, however, auto-rotation is implemented only for edge and end_piece tiles (doors, windows, furniture) and unconnected tiles (e.g. street lights).
For the active/rotating type, rotates_to specifies a Connection group the terrain should rotate towards (or rather, depend on).
For the passive/target type, connect_groups is used to add it to a connection group.
Terrain can only use terrain to rotate towards, while furniture can use both, terrain and furniture.
Presumably, either edge and end_piece, or unconnected will be used for a certain type, but rarely both at the same time. Therefore we give an example for windows using edge and end_piece, and for street lights using unconnected.
Windows and doors (and probably other types) can render differently, depending on where inside and outside is.
These elements are normally only represented by edge in multitile terms. In case of a wall next to the window not being visible, it will be end_piece.
For each of the two basic edge and end_piece directions (north-south, east-west), 2 or 4 sprite variants are required. Further, one unconnected variant is required as fallback.
(Green stands for rotates_to present, e.g. inside)
The full multitile would be defined like this:
{
"id": [ "t_window", "t_window_domestic" ],
"fg": "w_undefined",
"multitile": true,
"additional_tiles": [
{
"id": "edge",
"fg": [
"w_NS_W", "w_EW_S",
"w_NS_E", "w_EW_N",
"w_NS_BOTH", "w_EW_BOTH",
"w_NS_NONE", "w_EW_NONE"
]
},
{
"id": "end_piece",
"fg": [
"w_NS_W", "w_EW_S",
"w_NS_E", "w_EW_N",
"w_NS_BOTH", "w_EW_BOTH",
"w_NS_NONE", "w_EW_NONE"
]
},
{
"id": "unconnected",
"fg": [
"w_undefined",
"w_undefined"
]
}
]
}Note that the same sprites are used here for
edgeandend_piece.
The order of sprites ensures that the multitile also works with only the first 4 instead of all 8 sprites. It also makes it compatible with tilesets that don't use the rotates_to feature.
Doors and windows work out of the box without modifying terrain definitions, as the required group INDOORFLOOR is implied by the flags WINDOW, DOOR (active) and INDOORS (target/passive).
For unconnected tiles, rotates_to requires either 4 or 16 sprites.
To create these sprites, the normal multitile template can be used with slice_multitile.py.
The generated JSON needs to be re-arranged like this (names as generated by the script):
{
"id": "f_street_light",
"fg": "f_street_light_unconnected",
"multitile": true,
"additional_tiles": [
{
"id": "unconnected",
"fg": [
"f_street_light_end_piece_n",
"f_street_light_end_piece_e",
"f_street_light_end_piece_s",
"f_street_light_end_piece_w",
"f_street_light_corner_ne",
"f_street_light_corner_se",
"f_street_light_corner_sw",
"f_street_light_corner_nw",
"f_street_light_t_connection_n",
"f_street_light_t_connection_e",
"f_street_light_t_connection_s",
"f_street_light_t_connection_w",
"f_street_light_center",
"f_street_light_edge_ew",
"f_street_light_edge_ns",
"f_street_light_unconnected"
]
}
]
}A minimal version using only the 4 cardinal directions can be achieved with only 4 sprites:
{
...
"additional_tiles": [
{
"id": "unconnected",
"fg": [
"f_street_light_end_piece_n",
"f_street_light_end_piece_e",
"f_street_light_end_piece_s",
"f_street_light_end_piece_w"
]
}
]
}Note: When drawing using the template, keep in mind that neighbours to rotate towards are where connections are. The directions at the end of each generated file name are not the directions to rotate to! Rather, they are the opposite.
For terrain and furniture that connects as well as rotates, slice_multitile.py can be used on a 5x5 autotile template like this:
As for normal autotiles, the script also generates the requires JSON file. See there for the order of rotated elements.
Each JSON file can have either a single object or an array of one or more objects:
[
{ "id": "mon_zombie", "fg": "mon_zombie", "bg": "mon_zombie_bg" },
{ "id": "corpse_mon_zombie", "fg": "mon_zombie_corpse", "bg": "mon_zombie_bg" },
{ "id": "overlay_wielded_corpse_mon_zombie", "fg": "wielded_mon_zombie_corpse" }
]For graffitis, rotation can be used to distinguish between wall and floor drawings:
{
"id": "graffiti",
"fg": [ "graffiti_wall", "graffiti_floor" ],
}Weighted variations are also possible, and can be combined with rotation:
{
"id": "graffiti",
"fg": [
{ "weight": 1, "sprite": [ "graffiti_01_wall", "graffiti_01_floor" ] },
{ "weight": 1, "sprite": [ "graffiti_02_wall", "graffiti_02_floor" ] },
],
}Variant selection is based on the graffiti's text, so the same text will always result in the same variant shown.
It is possible to create graffitis for specifix texts.
The game looks up graffiti sprites by the pattern graffiti_THE_GRAFFITI_TEXT. If no such sprite is found, graffiti is used.
To create the sprite id, the graffiti's text is:
- truncated to 32 characters
- converted to capital letters
- all punctuation is removed
- special characters are removed
- spaces are replaced by underscores
So, e.g. all these texts would result in lookup for graffiti_NO_FUTURE: "no future", "No Future!!!", "no_future".
"Escape Pods & Vehicle Bay" becomes graffiti_ESCAPE_PODS__VEHICLE_BAY
[
{ // default sprite size
"width": 32,
"height": 32,
"pixelscale": 1 // Optional. Sets a multiplier for resizing a tileset. Defaults to 1.
}, {
"tiles.png": {} // Each tilesheet directory must have a corresponding object
}, { // with a single key, which will become the tilesheet output filename.
"expan.png": {} // Empty object means the default sprite size and no offsets.
}, {
"tree.png": {
"sprite_width": 64, // Overriding values example
"sprite_height": 80,
"sprite_offset_x": -16,
"sprite_offset_y": -48,
"pixelscale": 2, // Optional. Sets a multiplier for resizing tiles. Multiplied/on top of by tileset pixelscale. Defaults to 1.
"sprites_across": 4 // Change the sheet width, default is 16. Reducing empty space in the end helps a bit with CDDA memory consumption
}
}, {
"fillerhoder.png": { // Unknown keys like `source` will be ignored by `compose.py` and can be used as comments.
"source": "https://github.com/CleverRaven/Cataclysm-DDA/tree/b2d1f9f6cf6fae9c5076d29f9779e0ca6c03c222/gfx/HoderTileset",
"filler": true,
"exclude": [ // all subdirectories of this sheet directory mentioned here will not be visited
"dir_that_will_be_ignored",
"subdir/with/any/depth"
]
}
}, {
"fallback.png": {
"fallback": true
}
}
]Tilesheet directory names are expected to use the following format: pngs_{tilesheet_root_name}_{sprite_width}x{sprite_height} - such as pngs_tiles_32x32, pngs_expan_32x32, pngs_tree_64x80, etc. To improve performance, keep the number of tilesheets to a minimum.
"filler": true means the tilesheet is a filler; tile entries within it will be used only if IDs in them were not mentioned in any preceding tile entry. Sprites within a filler directory will be ignored if another one with the same name was already encountered. A filler tilesheet is useful when upgrading the art in a tileset: old, low-quality art can be placed on filler tilesheet and will be automatically replaced as better images are added to the non-filler tilesheets.
"fallback": true means the tilesheet is a fallback; it will be treated as a source of fallback ASCII character sprites. compose.py will also append the fallback tilesheet to the end of the tileset, and will add a "fallback.png" to tile_config.json if there is no fallback entry in tile_info.json.
A tilesheet can be an expansion from a mod. Each expansion tilesheet is a single id value, where the "rotates": false", and "fg": 0 keys are set. Expansion tile entry JSONs are the only tile entry JSONs that may use an integer value for fg, and that value must be 0. Expansion tile entry JSONs must be located at the top layer of each tilesheet directory.
An optional file called layering.json can be provided. This file defines "layer contexts" (referred to in JSON as "layer variants"), or entries for drawing items/fields differently based on furniture/terrain they're placed on. A default layering.json is provided with the repository.
{
"variants": [
{
"context": "f_desk",
"item_variants": [
{
"item": "laptop",
"sprite": [{"id": "desk_laptop", "weight": 1}],
"layer": 90,
"offset_x": 16,
"offset_y": -48
},
{
"item": "pen",
"sprite": [{"id": "desk_pen_1", "weight": 2}, {"id": "desk_pen_2", "weight": 2}],
"layer": 100
}
],
"field_variants": [
{
"field": "fd_fire",
"sprite": [{"id": "desk_fd_fire", "weight": 1}],
"offset_x": 16,
"offset_y": -48
}
]
}
]
}In this example, we provide the context tile f_desk and multiple items that will display differently while placed on it -- a pen using desk_pen_1 or desk_pen_2, and a laptop using desk_laptop. fd_fire, a field, will use the sprite desk_fd_fire on f_desk.
"context": "f_desk" the furniture or terrain that this should apply to. "context" can also be exactly one JSON flag placed in an array, which will display the given sprite for any furniture/terrain that has that flag.
"append_variants": an additional suffix automatically appended to sprite names from the item name, e.g. "_postup" for sprites of items posted on walls. The suffix must begin with an underscore '_'. The expected sprite name format (see Hardcoded IDs above for sprite name formats) for using "append_variants" is:
"item name" + "append_variants"
Example: american_flag_hoisted or national_flag_var_indian_flag_postup
Example usage of flag context and append_variants:
{
"variants": [
{
"context": [ "WALL" ],
"append_variants": "_postup",
"item_variants": [
{ "item": "american_flag", "layer": 90,"item_variants": the definitions for what items will have contextual sprites. Note: has nothing to do with item variants, this is really item_(layer)_variants.
"item": "laptop" the item id. (only supported in item_variants)
"layer": 100 this defines the order the sprites will draw in. 1 drawing first 100 drawing last (so 100 ends up on top). This only works for items, Fields are instead drawn in the order they are stacked on the tile.
"sprite": [{"id": "desk_pen_1", "weight": 2}, {"id": "desk_pen_2", "weight": 2}] an array of the possible sprites that can display. Multiple sprites can be provided with specific weights and will be selected at random for each item. If not provided, defaults to item name.
"offset_x": 16, "offset_y": -48 optional sprite offset. Defaults to 0 if not provided.
"field_variants": the definitions for what fields will have a variant sprite.
"field": "fd_fire" the field id. (only supported in field_variants)
"sprite": [{"id": "desk_fd_fire", "weight": 1}] an array of the possible sprites that can display. Multiple sprites can be provided with specific weights and will be selected at random based on map position.
"offset_x": 16, "offset_y": -48 optional sprite offset. Defaults to 0 if not provided.
compose.py [-h] [--use-all] [--obsolete-fillers] [--palette] [--palette-copies] source_dir [output_dir]
source_dir - the compositing tileset directory.
output_dir will be set to the source_dir unless provided separately. Expected to have tileset.txt and fallback.png.
--use-all: instead of warning about unused sprites, will treat their root name as the id value to use them as fg for. In other words, just naming your sprite overlay_wielded_spear_survivor.png will imply this tile entry unless any tile entry already references overlay_wielded_spear_survivor in a fg or bg value:
{
"id": "overlay_wielded_spear_survivor",
"fg": "overlay_wielded_spear_survivor"
}--obsolete-fillers: print which fillers were skipped and are thus ready to be removed.
--palette: Quantize all tilesheets to 8bpp colormaps. May severely reduce quality as there is only 256 possible colors but reduces file size.
--palette-copies: Output copies of tilesheet files quantized to 8bpp palette with .png8 extension. Intended for external detection if conversion was lossless.
Requires pyvips module, see below.
- Install Python with the latest installer https://www.python.org/downloads/windows/ (do not uncheck setting up the
pyshortcut unless you know what you are doing, check 'add Python to PATH'.)
Installation of pyvips can be skipped if you are planning to use updtset.cmd - see below. Otherwise:
- Open Console (Window key +
Rkey, typecmdand hitEnter) - Install pyvips with these commands:
py -m pip install --upgrade pip
py -m pip install --user pyvips
- Extract the latest libvips distribution to a folder (get the
vips-dev-w64-web-#.#.#.zipNOT thevips-dev-w64-all-#.#.#.zip) https://libvips.github.io/libvips/install.html - Press start menu and search for "
environment variables". - Alternatively go to
Control Panel > System > Advanced System Settings > Environment Variables - In the
User variablessection, selectPathand clickEdit. - Select an empty line and press
New - Copy and paste the path to the extracted
vips-dev-#.##\binfolder, it should look something likeC:\Users\username\Downloads\vips-dev-8.10\bin - If you have the Console open, close it so the changes take effect.
Navigate on Console to a directory with the script you want to launch.
Prefix the script filename with py , like this: py compose.py --use-all --obsolete-fillers pathToYourTileset pathToYourOutputFolder
Alternatively you can copy updtset.cmd from CDDA-Tilesets\tools to your Desktop, right click on it, select Edit, change four variables on the top part. Then you can just doubleclick on it and get Tileset updated.
It is recommended to bind a key to the update tileset action, so you do not need to restart the game after composing the tileset. E.g. F12 is usually unused.
TODO, please ask if you need it or send suggestions if you want to help
TODO, please ask if you need it or send suggestions if you want to help
In order to be included in the distribution of the game, a tileset must meet the following criteria:
- Licensing: ALL ART must be distributed under a CC-BY-SA 3.0 license or compatible. Any exceptions cannot be tolerated. If an art item's license is unclear it cannot be included.
- Crediting: Appropriate crediting as requested by artists must be met. You probably don't need to be told this, adding a credits.txt costs you nothing.
- Maintenance: A tileset must have had at least one PR updating its art since the previous stable release to be included in subsequent stable releases. While a formal maintainer isn't required for a tileset, it's much more likely that sets will not be marked obsolete if they have someone to speak up for them.
- Imagery: in general we do not have rules about imagery and content in tilesets, but we may request changes or refuse admission if a set includes overt hate imagery (swastikas for example).
Prior to October 2019, when compose.py was made, sprite indices in tile_config.json had to be calculated by hand. Following is a description for them.
Each tilesheet contains 1 or more sprites with the same width and height. Each tilesheet contains one or more rows of exactly 16 sprites. Sprite index 0 is special and the first sprite of the first tilesheet in a tileset should be blank. Indices run sequentially through each sheet and continue incrementing for each new sheet without resetting, so index 32 is the first sprite in the third row of the first sheet. If the first sheet has 320 sprites in it, index 352 would be the first sprite of the third row of the second sheet.
Each legacy tileset has a tile_config.json describing how to map the contents of a sprite sheet to various tile identifiers, different orientations, etc. The ordering of the overlays used for displaying mutations can be controlled as well. The ordering can be used to override the default ordering provided in mutation_ordering.json. Example:
{ // whole file is a single object
"tile_info": [ // tile_info is mandatory
{
"height": 32,
"width": 32,
"iso" : true, // Optional. Indicates an isometric tileset. Defaults to false.
"pixelscale" : 2 // Optional. Sets a multiplier for resizing a tileset. Defaults to 1.
}
],
"tiles-new": [ // tiles-new is an array of sprite sheets
{ // alternately, just one "tiles" array
"file": "tiles.png", // file containing sprites in a grid
"tiles": [ // array with one entry per tile
{
"id": "10mm", // ID is how the game maps things to sprites
"fg": 1, // lack of prefix mostly indicates items
"bg": 632, // fg and bg can be sprite indexes in the image
"rotates": false
},
{
"id": "t_wall", // "t_" indicates terrain
"fg": [2918, 2919, 2918, 2919], // 2 or 4 sprite numbers indicates pre-rotated
"bg": 633,
"rotates": true,
"multitile": true,
"additional_tiles": [ // connected/combined versions of sprite
{ // or variations, see below
"id": "center",
"fg": [2919, 2918, 2919, 2918]
},
{
"id": "corner",
"fg": [2924, 2922, 2922, 2923]
},
{
"id": "end_piece",
"fg": [2918, 2919, 2918, 2919]
},
{
"id": "t_connection",
"fg": [2919, 2918, 2919, 2918]
},
{
"id": "unconnected",
"fg": 2235
}
]
},
{
"id": "vp_atomic_lamp", // "vp_" vehicle part
"fg": 3019,
"bg": 632,
"rotates": false,
"multitile": true,
"additional_tiles": [
{
"id": "broken", // variant sprite
"fg": 3021
}
]
},
{
"id": "t_dirt",
"rotates": false,
"fg": [
{ "weight":50, "sprite":640}, // weighted random variants
{ "weight":1, "sprite":3620},
{ "weight":1, "sprite":3621},
{ "weight":1, "sprite":3622}
]
},
{
"id": [
"overlay_mutation_GOURMAND", // character overlay for mutation
"overlay_mutation_male_GOURMAND", // overlay for specified gender
"overlay_mutation_active_GOURMAND" // overlay for activated mutation
],
"fg": 4040
}
]
},
{ // second entry in tiles-new
"file": "moretiles.png", // another sprite sheet
"tiles": [
{
"id": ["xxx","yyy"], // define two ids at once
"fg": 1,
"bg": 234
}
]
}d
],
"overlay_ordering": [
{
"id" : "WINGS_BAT", // mutation name, in a string or array of strings
"order" : 1000 // range from 0 - 9999, 9999 being the topmost layer
},
{
"id" : [ "PLANTSKIN", "BARK" ], // mutation name, in a string or array of strings
"order" : 3500 // order is applied to all items in the array
},
{
"id" : "bio_armor_torso", // Overlay order of bionics is controlled in the same way
"order" : 500
}
]
}This is a Python script that will convert a legacy tileset into a compositing tileset. It reads the tile_config.json and assigns semi-arbitrary file names to each sprite index. Then it changes all sprite index references to file names, breaks up tile_config.json into many small tile entry JSON files with arbitrary file names, and writes each sprite into a separate file.
It requires the pyvips module to perform the image processing.
It takes a single mandatory argument, which is the path to the tileset directory. For example:
python3 tools/gfx_tools/decompose.py gfx/ChestHole16Tileset will convert the legacy ChestHole16 tileset to a compositing tileset.
decompose.py creates a sufficient directory hierarchy and file names for a tileset to be compositing, but it is machine-generated and will be badly organized. New compositing tilesets should use more sensible file names and a better organization.
It shouldn't be necessary to run decompose.py very often. Legacy tilesets should only need to be converted to composite tilesets one time.