The toplevel [terrain_graphics] tag
For information about the multi-hex tiling system, see MultiHexTutorial
In terrain graphics, in Wesnoth 1.8.x all images are assumed to be .png and relative to images/terrain/. For example, writing 'image=grassland' means that the image file is images/terrain/grassland.png. In Wesnoth 1.9.x the .png extension is required. This means that TerrainGraphicsWML is incompatible from 1.8.x to 1.9.x.
The multi-hex tiling system adds a new top-level element to WML, [terrain_graphics]. A building rule is used to specify images to place when terrains are in a certain formation. When a building rule is applied to a map, it is applied once to each coordinate on the map; when it is applied to a coordinate then that coordinate is considered the base. All locations in [terrain_graphics] are relative to the base.
The following keys/tags are recognized:
- x,y: constrains the rule to given absolute map coordinates. Primarily useful to place map-specific features.
- mod_x,mod_y: (Version 1.13.1 and later only) constrains the rule to absolute map coordinates which are multiples of the given values. For example, mod_x=4 would only match locations with an x coordinate of 4, 8, 12, 16, etc.
- [tile]: whenever a building rule is applied, each [tile] tag corresponds to a tile on the map. The corresponding tile must match each condition contained in [tile] for the [tile] tag to match. All [tile] tags must match in order for a rule to match. If the rule for a [tile] tag is applied, each action within [tile] will be executed on the tile corresponding to that [tile] tag
- x,y: standard coordinates - the location of the corresponding tile relative to the base.
- pos: a shortcut to specifying coordinates. Used in combination with map
- type: a comma-separated list of terrain codes (See TerrainWML, data/terrain.cfg). In order for a tile to match this condition, it must be one of the terrains specified. However, if the string is preceded by "!", the terrain must not be listed in order to match. If the string is '*', or if it is empty, any tile matches.
- name: for animated terrain this takes the form of a comma separated list of images with durations specified after ':'. A square bracket expansion can also be used as in AnimationWML (see in example below).
- no_draw (default: no): (Version 1.13.5 and later only) whether to actually draw images of this rule onto this hex.
- set_flag: a comma-separated list of strings or square bracket expansion as in AnimationWML. Attaches flags from that list to the corresponding tile if the rule matches. The only difference a flag makes is being detected by has_flag and no_flag in [tile]. This is determined by the order of the [terrain_graphics] tags; a tag after another one cannot influence it. See also has_flag, no_flag
- has_flag: a comma-separated list of strings or square bracket expansion as in AnimationWML. Matches if all flags in that list are attached to the corresponding tile. Flags are attached using the set_flag key.
- no_flag: a comma-separated list of strings or square bracket expansion as in AnimationWML. Matches if none of the flags in that list are attached to the corresponding tile. Flags are attached using the set_flag key.
- set_no_flag: helper combining set_flag and no_flag. Same effect as using them with the same flags. Added because it's the most common use; set_flag or no_flag can still be used to add flags in one group only.
- [image]: images specified as a subtag to [tile] sets the images for a single tile.
- layer: an integer, usually negative. The more negative it is, the earlier it is drawn, and thus the farther "back" it is when compositing the terrain images together.
- name: the image to apply on this tile if appropriate (See ImagePathFunctionWML for additional options).
- random_start (default: yes): Tells engine to start animation at random point instead of at the beginning for every tile (Version 1.13.9 and later only) If given a positive integer, limits the range of the random shift of the start time to the given amount of milliseconds. For example, if the animation duration is 700ms, then random_start=yes and random_start=700 are equivalent, whereas random_start=100 limits the start times of different instances of the animation to be at most 100ms apart.
- base: specifies the point at which the image is considered to be for layering purposes. base is specified as x,y where x and y indicate distances in pixels from the top-left corner of the image. This is translated to a certain pixel on the map, and all images with the base attribute are drawn from top-to-bottom in terms of these specified pixel positions on the map.
- [variant]: an alternate image to use for differing times of day
- tod: the time of day for which this variant applies. Accepts a comma separated list of times of day.
- name: the image to apply on this tile if appropriate
- random_start (default: yes): Tells engine to start animation at random point instead of at the beginning for every tile
- has_flag (Version 1.13.1 and later only) comma-separated list of flags that the tile must have for this variant to apply.
- [image]: image may also be used directly in the rule, to specify multihex images. The following additional attributes are recognized for multihex images (as well as all the ones for images within [tile]).
- center: specifies the point which the image will be centered on. If it is not specified, the image will instead be aligned with the top left corner of the tile.
- probability: the percent probability for each position that if the position matches, then the rule will be applied. Default is 100(%). See Cumulative_Probabilities for mathematical complications.
- rotations: 6 comma(,) separated input strings. A rule that contains this key is not actually checked against the terrain; it instead is used as a template to create 6 new rules, each corresponding to a rotated version of the current rule. Whenever a rotated version is applied, instances of @(at-sign)R0, @R1, ... @R6 in attributes in the [terrain_graphics] tag will be adjusted by the corresponding amount and replaced with the letters specified by that numbered rotation in the rotations list. Each value corresponds to the rotated version that is -Pi/3 (60° clockwise) from the previous version; the first value corresponds to the unrotated version.
For example, if rotations=n,ne,se,s,sw,nw and it is being rotated 120°, then "@R0"->"@R2"->"se", "@R1"->"@R3"->"s", ... "@R6"->"@R1"->"ne".
Basically the important thing is that this lets the rule be applied in any of the six hex-directions, allowing you to adjust the name of the image files automatically.
- set_flag,has_flag, no_flag: shortcuts to putting these in the [tile] subtags; unbound attributes will apply to all [tile] subtags.
- map: a shortcut for defining [tile] tags with type conditions. Inputs a multi-line string value visually describing the map. The lines are cut into words of 4 characters, which correspond to [tile] tags. The line types alternate between lines corresponding to relatively even-abciss tiles and lines preceded by two spaces corresponding to relatively odd-abciss tiles. Every two lines represent 1 row on the map.
A word is a 4-character shortcut to a [tile] tag. There are different types of words:
- Usually a word is interpreted as being the input to the type key of the corresponding [tile]. That is, it creates a [tile] with the attribute type=word.
- A word can also be a digit followed by 3 spaces. In this case, it is a shortcut to the [tile] with the attribute pos=word. This is called anchoring.
In 1.3, the format is basically the same but the following changes are made
- A word no longer needs to be 4 characters but is comma separated and spaces and tabs may be used for padding
- The 2 spaces for odd lines in no longer used, instead a leading comma is used on these lines (before the comma spaces and tabs are allowed for padding)
- A word may only be a dot a star or an anchor. The terrain letter format was not used and hard to support in the new engine, so that support is dropped.
To define a north-south 2-tile mountain, the following syntax can be used:
[terrain_graphics] [tile] x=0 y=0 type=Mm set_no_flag="base" [/tile] [tile] x=0 y=1 type=Mm set_no_flag="base" [/tile] [image] name="mountain-n-s.png" [/image] [/terrain_graphics]
This represents a tile 1, and its six adjacent tiles 2, in the map notation.
., ., ., . , ., 2, ., . ., 2, 2, . , ., 1, ., . ., 2, 2, . , ., 2, ., .
To define an animated campfire at coordinates (4,5) with files "misc/fire-A01.png" to "misc/fire-A08.png" with an inter-frame transition time of 140, the following can be placed at the scenario top level (adapted from the CAMPFIRE macro):
[terrain_graphics] x,y=4,5 [tile] x=0 y=0 [image] layer=0 name="misc/fire-A[01~08].png:140" [/image] [/tile] [/terrain_graphics]