A Shop Like Thing

[edit]WML Tags

A: abilities, about, achievement, achievement_group, add_ai_behavior, 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 (replay, weapon), attack_anim, attacks (special, stats), avoid;

B: base_unit, background_layer, berserk, binary_path, break, brush;

C: campaign, cancel_action, candidate_action, capture_village, case, chance_to_hit, change_theme, chat, checkbox, choice, choose, clear_global_variable, clear_menu_item, clear_variable, color_adjust, color_palette, color_range, command (action, replay), continue, credits_group, 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 (credits, options), era, event, experimental_filter_ability, experimental_filter_ability_active, experimental_filter_specials, 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_student, filter_vision, filter_weapon, filter_wml, find_path, fire_event, firststrike, floating_text, found_item, for, foreach, frame;

G: game_config, get_global_variable, goal, gold, gold_carryover;

H: harm_unit, has_ally, has_attack, has_unit, has_achievement, 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, intro), illuminates, image (intro, terrain), 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, post_movement_anim, pre_movement_anim, primary_attack, primary_unit, print, progress_achievement, 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_trait, remove_unit_overlay, repeat, replace_map, replace_schedule, replay, replay_start, reset_fog, resistance (ability, unit), resistance_defaults, resolution, resource, return, role, rule;

S: save, scenario, screen_fade, scroll, scroll_to, scroll_to_unit, secondary_attack, secondary_unit, section, select_unit, sequence, set_achievement, set_extra_recruit, set_global_variable, set_menu_item, set_recruit, set_specials, set_variable, set_variables, sheath_weapon_anim, show_if (message, objective, set_menu_item), show_objectives, side, skirmisher, slider, 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_defense_on, store_unit_type, store_unit_type_ids, store_villages, story, swarm, sub_achievement, switch, sync_variable;

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

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

V: value, variable, variables, variant, variation, victory_anim, village, vision_costs, volume;

W: while, wml_message, wml_schema;

Z: zoom;

A Shop Like Thing

In this page you can see different techniques of creating a shop.

Example implementations

There's a discussion thread that started in 2019 (Wesnoth 1.14).

The Colosseum add-on's shop

The add-on Colosseum has a shop that's intended to be usable by other add-ons. Basic usage is given in the readme file in the add-on.

Simple

Use this macro to place a moveto event in your scenario that defines a magic-items shop. Argument is a StandardLocationFilter.

Used macros:

• VARIABLE_CONDITIONAL (from file utils.cfg)
• CLEAR_VARIABLE (from file utils.cfg)
• WEAPON_SPECIAL_MAGICAL (from fileabilities.cfg)

#define CREATE_SIMPLE_SHOP FILTER
   [event]
       name=moveto
       first_time_only=no
       [filter]
           # this is not a macro. It is a argument token, 
           # which will be substituted with argument value
           {FILTER}
       [/filter]
       [store_gold]
           side=$side_number
           variable=css_gold
           # it is bad idea to use simple variable names like "gold" inside macro
           # because you can overwrite values of variables,
           # which was defined outside of this macro and was supposed to be used for
           # anything else. To prevent any side effects, preceed macro-specific variables
           #  with abbreviation of macro name
       [/store_gold]
       # this is easiest way to create menu in the game.
       # you just define each value and player sees them anytime he trigger this event
       [message]
           speaker=narrator
           message=_ "What items would you like to purchase?"
           image=wesnoth-icon.png

           [option]
               message=_ "140 GP: Sharpen Melee Weapon, damage:+2"
               [show_if]
                   {VARIABLE_CONDITIONAL gold greater_than 140}
               [/show_if]
               [command]
                   [gold]
                       amount=-140
                       side=$side_number
                   [/gold]
                   [object]
                       silent = yes
                       [effect]
                           apply_to=attack
                           # You need to specify filter for your effect
                           # but you should't use [filter] tags
                           # [filter]
                           range=melee
                           # [/filter]
                           increase_damage=2
                       [/effect]
                   [/object]
               [/command]
           [/option]

           [option]
               message=_ "150 GP: Enchance Ranged Weapon, damage +2"
               [show_if]
                   {VARIABLE_CONDITIONAL gold greater_than 150}
               [/show_if]
               [command]
                   [gold]
                       side=$side_number
                       amount=-150
                   [/gold]
                   [object]
                       silent = yes
                       [effect]
                           apply_to=attack
                           # [filter]
                           range=ranged
                           # [/filter]
                           increase_damage=2
                       [/effect]
                   [/object]
               [/command]
           [/option]

           [option]
               message=_ "150 GP: Crystal Orb, damage +2 on magical attack"
               [show_if]
                   {VARIABLE_CONDITIONAL gold greater_than 150}
               [/show_if]
               [command]
                   [gold]
                       amount=-150
                       side=$side_number
                   [/gold]
                   [object]
                       silent = yes
                       [effect]
                           apply_to=attack
                           # [filter]
                           special=chance_to_hit
                           # [/filter]
                           increase_damage=2
                       [/effect]
                   [/object]
               [/command]
           [/option]

           [option]
               message=_ "250 GP: Toughness Increase Scroll, Max HP+10"
               [show_if]
                   {VARIABLE_CONDITIONAL gold greater_than 250}
               [/show_if]
               [command]
                   [gold]
                       amount=-250
                       side=$side_number
                   [/gold]
                   [object]
                       silent = yes
                       [effect]
                           apply_to=hitpoints
                           increase_total=10
                       [/effect]
                   [/object]
               [/command]
           [/option]

           [option]
               message=_ "400 GP: Seven-League Boots, gives MP of 10"
               [show_if]
                   {VARIABLE_CONDITIONAL gold greater_than 400}
               [/show_if]
               [command]
                   [gold]
                       amount=-400
                       side=$side_number
                   [/gold]
                   [object]
                       silent = yes
                       [effect]
                           apply_to=movement
                           set=10
                       [/effect]
                   [/object]
               [/command]
           [/option]

           [option]
               message=_ "400 GP: Boot Upgrade, MP+1"
               [show_if]
                   {VARIABLE_CONDITIONAL gold greater_than 400}
               [/show_if]
               [command]
                   [gold]
                       amount=-400
                       side=1
                   [/gold]
                   [object]
                       silent = yes
                       [effect]
                           apply_to=movement
                           increase=1
                       [/effect]
                   [/object]
               [/command]
           [/option]

           [option]
               message=_ "All GP: Healing Fountain, HP:+50"
               [show_if]
                   {VARIABLE_CONDITIONAL gold greater_than 0}
               [/show_if]
               [command]
                   [gold]
                       amount=-$css_gold
                       side=$side_number
                   [/gold]
                   [object]
                       silent = yes
                       [effect]
                           apply_to=hitpoints
                           increase=50
                           violate_max=1
                       [/effect]
                   [/object]
               [/command]
           [/option]

           [option]
               message=_ "300 GP: Rage Stone, add a melee swing"
               [show_if]
                   {VARIABLE_CONDITIONAL gold greater_than 300}
               [/show_if]
               [command]
                   [gold]
                       amount=-300
                       side=$side_number
                   [/gold]
                   [object]
                       silent = yes
                       [effect]
                           apply_to=attack
                           # [filter]
                           range=melee
                           # [/filter]
                           increase_attacks=1
                       [/effect]
                   [/object]
               [/command]
           [/option]

           [option]
               message=_ "350 GP: Sight Stone, add a ranged attack"
               [show_if]
                   {VARIABLE_CONDITIONAL gold greater_than 350}
               [/show_if]
               [command]
                   [gold]
                       amount=-350
                       side=$side_number
                   [/gold]
                   [object]
                       silent = yes
                       [effect]
                           apply_to=attack
                           # [filter]
                           range=ranged
                           # [/filter]
                           increase_attacks=1
                       [/effect]
                   [/object]
               [/command]
           [/option]

           [option]
               message=_ "350 GP: Fire Scepter, adds 8-1 ranged magical fire"
               [show_if]
                   {VARIABLE_CONDITIONAL gold greater_than 350}
               [/show_if]
               [command]
                   [gold]
                       amount=-350
                       side=$side_number
                   [/gold]
                   [object]
                       silent = yes
                       [effect]
                           apply_to=new_attack
                           name=Fire Scepter
                           type=fire
                           range=ranged
                           [specials]
                               {WEAPON_SPECIAL_MAGICAL}
                           [/specials]
                           damage=8
                           number=1
                       [/effect]
                   [/object]
               [/command]
           [/option]

           [option]
               message=_ "350GP: Ice Scepter, adds 8-1 ranged magical ice"
               [show_if]
                   {VARIABLE_CONDITIONAL gold greater_than 350}
               [/show_if]
               [command]
                   [gold]
                       amount=-350
                       side=$side_number
                   [/gold]
                   [object]
                       silent = yes
                       [effect]
                           apply_to=new_attack
                           name=Ice Scepter
                           type=cold
                           range=ranged
                           [specials]
                               {WEAPON_SPECIAL_MAGICAL}
                           [/specials]
                           damage=8
                           number=1
                       [/effect]
                   [/object]
               [/command]
           [/option]
       [/message]
       {CLEAR_VARIABLE css_gold}
   [/event]
#enddef

Feature suggestions

Allow multiple choices in single dialog

Instead of exiting after the player buys one item, a better shop allows the player to buy more than one. This can be done with an infinite loop, which exits when the player chooses the "exit" option. For example, the Colosseum's implementation:

   [while]
       [variable]
           name=finished
           boolean_equals=no
       [/variable]
       [do]
           # ...
               [option]
                   label= _ "Done"
                   [command]
                       {VARIABLE finished yes}
                   [/command]
               [/option]
           # ...
       [/do]
   [/while]

Optionally enter the shop

Instead of using moveto events, you can use set_menu_item to allow the player to decide whether they want to enter the shop, by adding an "Enter Shop" option to the right-click menu.

See Also

• UsefulWMLFragments
• ReferenceWML