Difference between revisions of "StandardLocationFilter"

From The Battle for Wesnoth Wiki
(no "terrain letters" anymore.)
(Added an in-depth clarification of how radius= works.)
Line 48: Line 48:
 
   [/and]
 
   [/and]
 
   [/have_location]
 
   [/have_location]
 
+
Note that the use of [and] here causes the radius to have a very different meaning. Normally, all of the criteria besides radius are checked, producing a set of hexes to which the radius is applied. This means, for example, that if you're trying to find "a hex without a unit on it within 5 hexes of (15, 23)", the code:
 +
  [have_location]
 +
  x,y=15,23
 +
  radius=5
 +
  [not]
 +
    [filter]
 +
    [/filter]
 +
  [/not]
 +
  [have_location]
 +
will not work! First, it looks for a hex with x=15, y=23 without a unit on it. Then, it returns that hex and all hexes within 5 of it. If (15, 23) happens to be occupied, then it will return no hexes, because "all hexes within 5 hexes of (no hexes)" is still "no hexes". Instead, put an [and] around the x,y and radius requirements, and it will separately find "(15, 23) and all hexes within 5 of it" and "each of those hexes that doesn't have a unit on it", producing the desired result.
 
[[Category: WML Reference]]
 
[[Category: WML Reference]]

Revision as of 05:35, 5 February 2009

[edit]WML Tags

A:

abilities, about, add_ai_behavior, advance, advanced_preference, advancefrom, advancement, advances, affect_adjacent, ai, allied_with, allow_end_turn, allow_extra_recruit, allow_recruit, allow_undo, and, animate, animate_unit, animation, aspect, attack, attack_anim, attacks, avoid;

B:

base_unit, berserk, binary_path, break, brush;

C:

campaign, cancel_action, candidate_action, capture_village, case, chance_to_hit, change_theme, chat, choose, clear_global_variable, clear_menu_item, clear_variable, color_adjust, color_range, command (action, replay), continue, criteria;

D:

damage, death, deaths, default, defend, defends, defense, delay, deprecated_message, destination, difficulty, disable, disallow_end_turn, disallow_extra_recruit, disallow_recruit, do, do_command, drains, draw_weapon_anim;

E:

editor_group, editor_music, editor_times, effect, else (action, animation), elseif, endlevel, end_turn (action, replay), enemy_of, engine, entry, era, event, extra_anim;

F:

facet, facing, fake_unit, false, feedback, female, filter (concept, event), filter_adjacent, filter_adjacent_location, filter_attack, filter_attacker, filter_base_value, filter_condition, filter_defender, filter_enemy, filter_location, filter_opponent, filter_own, filter_owner, filter_radius, filter_recall, filter_second, filter_second_attack, filter_self, filter_side, filter_vision, filter_weapon, filter_wml, find_path, fire_event, firststrike, floating_text, for, foreach, frame, full_heal;

G:

game_config, get_global_variable, goal, gold, gold_carryover;

H:

harm_unit, has_ally, has_attack, has_unit, have_location, have_unit, heal_on_hit, heal_unit, healed_anim, healing_anim, heals, hide_help, hide_unit, hides;

I:

idle_anim, if (action, animation), illuminates, image, init_side, insert_tag, inspect, item, item_group;

J:

jamming_costs, join;

K:

kill, killed;

L:

label, language, leader, leader_goal, leadership, leading_anim, levelin_anim, levelout_anim, lift_fog, limit, literal, load_resource, locale, lock_view, lua;

M:

male, menu_item, message, micro_ai, missile_frame, modification, modifications, modify_ai, modify_side, modify_turns, modify_unit, modify_unit_type, move, move_unit, move_unit_fake, move_units_fake, movement_anim, movement costs, movetype, multiplayer, multiplayer_side, music;

N:

not, note;

O:

object, objective, objectives, on_undo, open_help, option, options, or;

P:

part, petrifies, petrify, place_shroud, plague, poison, portrait, post_movement_anim, pre_movement_anim, primary_attack, primary_unit, print, put_to_recall_list;

R:

race, random_placement, recall (action, replay), recalls, recruit, recruit_anim, recruiting_anim, recruits, redraw, regenerate, remove_event, remove_item, remove_object, remove_shroud, remove_sound_source, remove_time_area, remove_unit_overlay, repeat, replace_map, replace_schedule, replay, replay_start, reset_fog, resistance (ability, unit), resistance_defaults, resource, return, role, rule;

S:

save, scenario, scroll, scroll_to, scroll_to_unit, secondary_attack, secondary_unit, section, select_unit, sequence, set_extra_recruit, set_global_variable, set_menu_item, set_recruit, set_specials, set_variable, set_variables, sheath_weapon_anim, show_if (message, set_menu_item), show_objectives, side, skirmisher, slow, snapshot, sound, sound_source, source (replay, teleport), special_note, specials, split, stage, standing_anim, statistics, status, store_gold, store_items, store_locations, store_map_dimensions, store_reachable_locations, store_relative_direction, store_side, store_starting_location, store_time_of_day, store_turns, store_unit, store_unit_defense, store_unit_type, store_unit_type_ids, store_villages, story, swarm, switch, sync_variable;

T:

target, team, teleport (ability, action), teleport_anim, terrain, terrain_defaults, terrain_graphics, terrain_mask, terrain_type, test, test_condition, text_input, textdomain, theme, then, tile, time, time_area, topic, toplevel, trait, transform_unit, traveler, true, tunnel, tutorial;

U:

unhide_unit, unit, unit_overlay, unit_type, unit_worth, units, unlock_view, unpetrify, unstore_unit, unsynced;

V:

value, variable, variables, variation, victory_anim, village, vision_costs, volume;

W:

while, wml_message, wml_schema;

Z:

zoom;

From FilterWML, this is the standard way of filtering on locations. The following attributes and sub-tags are permitted:

  • time_of_day: filter matches only on a given time of day (one of lawful, chaotic or neutral).
  • terrain: comma separated list of terrains. (See also: Filtering Terrains).
  • x,y: the same as in the unit filter; supports any range (notes)
  • [filter]: a StandardUnitFilter; if present a unit must also be there
  • owner_side: the side of the owner, if this location is an owned village.
  • find_in: name of an array or container variable; if present, the location will not match unless it is also found stored in the variable
  • radius: matches if any location within the radius matches this filter (notes)
  • [filter_radius]: a standard location filter; normally the radius extends outwards from matching locations one step at a time without checking any additional information-- however, if this tag is present, the radius will be restricted so that it can only expand outwards in the directions where it passes the given location filter
  • [and]: an extra location filter. Unless a location matches the [and] filter, then it will be excluded. Note: [and],[or],and [not] extra location filters are considered after everything else in the containing filter (except radius, which is considered last in 1.3.8 and greater); they are then processed in the order encountered.
  • [or]: an extra location filter. If a location matches the [or] filter, then it will count as a match regardless of conditions in previous filters or the containing filter.
  • [not]: an extra location filter. If a location matches the [not] filter, then that location will be excluded.
  • [filter_adjacent_location]: a standard location filter; if present the correct number of adjacent locations must match this filter
    • count: a number, range, or comma separated range; default "1-6"
    • adjacent: a comma separated list of directions; default "n,ne,se,s,sw,nw"

Notes about Coordinate Usage

When specifying coordinates, the following keys are used:

  • x: the first coordinate
  • y: the second coordinate

While some locations should only be one hex (like the starting position of a unit), others filter over multiple hexes. The following syntax is used to filter over multiple hexes:

Dashes(-) are used to have the location be a range of hexes. There must be values before and after the dash; everything in between these numbers (inclusively) is part of the range.

Commas(,) are used to separate coordinates into a list. The x and y lists are then paired up, with each pair representing one hex or range.

Note: although the ordering of locations in a list generally does not matter, the action [move_unit_fake] takes in a list of hexes, and moves an image onto each of those hexes in order.

Notes about Radius Usage

If you aren't storing any locations successfully, it may be because you put the radius or filters in the wrong place for them to combine correctly.
 [have_location]
 terrain=Gg^Vh
 [and]
   x=$x1
   y=$y1
   radius=1
 [/and]
 [/have_location]

Note that the use of [and] here causes the radius to have a very different meaning. Normally, all of the criteria besides radius are checked, producing a set of hexes to which the radius is applied. This means, for example, that if you're trying to find "a hex without a unit on it within 5 hexes of (15, 23)", the code:

 [have_location]
 x,y=15,23
 radius=5
 [not]
   [filter]
   [/filter]
 [/not]
 [have_location]

will not work! First, it looks for a hex with x=15, y=23 without a unit on it. Then, it returns that hex and all hexes within 5 of it. If (15, 23) happens to be occupied, then it will return no hexes, because "all hexes within 5 hexes of (no hexes)" is still "no hexes". Instead, put an [and] around the x,y and radius requirements, and it will separately find "(15, 23) and all hexes within 5 of it" and "each of those hexes that doesn't have a unit on it", producing the desired result.