wesnoth/data/ai/lua/generic_recruit_engine.lua
mattsc cbf99a6f00 Fred ExpAI recruiting: set initial conditions for first recruit
Without this, the AI always starts with whatever it considers the best unit without taking the level bonus into account. This mostly only matters when one sets high_level_fraction to a very large value (1 or larger) in order to force only high-level recruits. In other cases it makes no, or no significant, difference.
2019-10-08 13:24:13 -07:00

1047 lines
52 KiB
Lua

return {
-- init parameters:
-- ai_cas: an object reference to store the CAs and associated data
-- the CA will use the function names ai_cas:recruit_rushers_eval/exec, so should be referenced by the object name used by the calling AI
-- ai_cas also has the functions find_best_recruit, find_best_recruit_hex and analyze_enemy_unit added to it
-- find_best_recruit, find_best_recruit_hex may be useful for writing recruitment code separately from the engine
-- params: parameters to configure recruitment
-- score_function: function that returns the CA score when recruit_rushers_eval wants to recruit
-- (default returns the RCA recruitment score)
-- randomness: a measure of randomness in recruitment
-- higher absolute values increase randomness, with values above about 3 being close to completely random
-- (default = 0.1)
-- min_turn_1_recruit: function that returns true if only enough units to grab nearby villages should be recruited turn 1, false otherwise
-- (default always returns false)
-- leader_takes_village: function that returns true if and only if the leader is going to move to capture a village this turn
-- (default returns 'not ai.aspects.passive_leader')
-- enemy_types: array of default enemy unit types to consider if there are no enemies on the map
-- and no enemy sides exist or have recruit lists
-- Note: the recruiting code assumes full knowledge of units on the map and the recruit lists of other sides for the purpose of
-- finding the best unit types to recruit. It does not work otherwise. It assumes normal vision of the AI side (that is, it disregards
-- hidden enemy units) for determining from which keep hex the leader should recruit and on which castle hexes to recruit new units
init = function(ai_cas, params)
if not params then
params = {}
end
math.randomseed(os.time())
local AH = wesnoth.require "ai/lua/ai_helper.lua"
local M = wesnoth.map
local LS = wesnoth.require "location_set"
local recruit_data = {}
local no_village_cost = function(recruit_id)
return wesnoth.unit_types[recruit_id].cost+wesnoth.unit_types[recruit_id].level+wesnoth.sides[wesnoth.current.side].village_gold
end
local get_hp_efficiency = function (table, recruit_id)
-- raw durability is a function of hp and the regenerates ability
-- efficiency decreases faster than cost increases to avoid recruiting many expensive units
-- there is a requirement for bodies in order to block movement
-- There is currently an assumption that opponents will average about 15 damage per strike
-- and that two units will attack per turn until the unit dies to estimate the number of hp
-- gained from regeneration
local effective_hp = wesnoth.unit_types[recruit_id].max_hitpoints
local unit = wesnoth.create_unit {
type = recruit_id,
random_traits = false,
name = "X",
random_gender = false
}
-- Find the best regeneration ability and use it to estimate hp regained by regeneration
local abilities = wml.get_child(unit.__cfg, "abilities")
local regen_amount = 0
if abilities then
for regen in wml.child_range(abilities, "regenerate") do
if regen.value > regen_amount then
regen_amount = regen.value
end
end
effective_hp = effective_hp + (regen_amount * effective_hp/30)
end
local hp_score = math.max(math.log(effective_hp/20),0.01)
local efficiency = hp_score/(wesnoth.unit_types[recruit_id].cost^2)
local no_village_efficiency = hp_score/(no_village_cost(recruit_id)^2)
table[recruit_id] = {efficiency, no_village_efficiency}
return {efficiency, no_village_efficiency}
end
local efficiency = {}
setmetatable(efficiency, { __index = get_hp_efficiency })
function poisonable(unit)
return not unit.status.unpoisonable
end
function drainable(unit)
return not unit.status.undrainable
end
function get_best_defense(unit)
local terrain_archetypes = { "Wo", "Ww", "Wwr", "Ss", "Gt", "Ds", "Ft", "Hh", "Mm", "Vi", "Ch", "Uu", "At", "Qt", "^Uf", "Xt" }
local best_defense = 100
for i, terrain in ipairs(terrain_archetypes) do
local defense = unit:defense(terrain)
if defense < best_defense then
best_defense = defense
end
end
return best_defense
end
function analyze_enemy_unit(enemy_type, ally_type)
local function get_best_attack(attacker, defender, defender_defense, attacker_defense, can_poison)
-- Try to find the average damage for each possible attack and return the one that deals the most damage.
-- Would be preferable to call simulate combat, but that requires the defender to be on the map according
-- to documentation and we are looking for hypothetical situations so would have to search for available
-- locations for the defender that would have the desired defense. We would also need to remove nearby units
-- in order to ensure that adjacent units are not modifying the result. In addition, the time of day is
-- assumed to be neutral here, which is not assured in the simulation.
-- Ideally, this function would be a clone of simulate combat, but run for each time of day in the scenario and on arbitrary terrain.
-- In several cases this function only approximates the correct value (eg Thunderguard vs Goblin Spearman has damage capped by target health)
-- In some cases (like poison), this approximation is preferred to the actual value.
local best_damage = 0
local best_attack
local best_poison_damage = 0
-- Steadfast is currently disabled because it biases the AI too much in favour of Guardsmen
-- Basically it sees the defender stats for damage and wrongfully concludes that the unit is amazing
-- This may be rectifiable by looking at retaliation damage as well.
local steadfast = false
for attack in wml.child_range(wesnoth.unit_types[attacker.type].__cfg, "attack") do
local defense = defender_defense
local poison = false
local damage_multiplier = 1
local damage_bonus = 0
local weapon_damage = attack.damage
for special in wml.child_range(attack, 'specials') do
local mod
if wml.get_child(special, 'poison') and can_poison then
poison = true
end
-- Handle marksman and magical
mod = wml.get_child(special, 'chance_to_hit')
if mod then
if mod.value then
if mod.cumulative then
if mod.value > defense then
defense = mod.value
end
else
defense = mod.value
end
elseif mod.add then
defense = defense + mod.add
elseif mod.sub then
defense = defense - mod.sub
elseif mod.multiply then
defense = defense * mod.multiply
elseif mod.divide then
defense = defense / mod.divide
end
end
-- Handle most damage specials (assumes all are cumulative)
mod = wml.get_child(special, 'damage')
if mod and mod.active_on ~= "defense" then
local special_multiplier = 1
local special_bonus = 0
if mod.multiply then
special_multiplier = special_multiplier*mod.multiply
end
if mod.divide then
special_multiplier = special_multiplier/mod.divide
end
if mod.add then
special_bonus = special_bonus+mod.add
end
if mod.subtract then
special_bonus = special_bonus-mod.subtract
end
if mod.backstab then
-- Assume backstab happens on only 1/2 of attacks
-- TODO: find out what actual probability of getting to backstab is
damage_multiplier = damage_multiplier*(special_multiplier*0.5 + 0.5)
damage_bonus = damage_bonus+(special_bonus*0.5)
if mod.value then
weapon_damage = (weapon_damage+mod.value)/2
end
else
damage_multiplier = damage_multiplier*special_multiplier
damage_bonus = damage_bonus+special_bonus
if mod.value then
weapon_damage = mod.value
end
end
end
end
-- Handle drain for defender
local drain_recovery = 0
local defender_attacks = defender.attacks
for i_d = 1,#defender_attacks do
local defender_attack = defender_attacks[i_d]
if (defender_attack.range == attack.range) then
for _,sp in ipairs(defender_attack.specials) do
if (sp[1] == 'drains') and drainable(attacker) then
-- TODO: calculate chance to hit
-- currently assumes 50% chance to hit using supplied constant
local attacker_resistance = attacker:resistance(defender_attack.type)
drain_recovery = (defender_attack.damage*defender_attack.number*attacker_resistance*attacker_defense/2)/10000
end
end
end
end
defense = defense/100.0
local resistance = defender:resistance(attack.type)
if steadfast and (resistance < 100) then
resistance = 100 - ((100 - resistance) * 2)
if (resistance < 50) then
resistance = 50
end
end
local base_damage = (weapon_damage+damage_bonus)*resistance*damage_multiplier
if (resistance > 100) then
base_damage = base_damage-1
end
base_damage = math.floor(base_damage/100 + 0.5)
if (base_damage < 1) and (attack.damage > 0) then
-- Damage is always at least 1
base_damage = 1
end
local attack_damage = base_damage*attack.number*defense-drain_recovery
local poison_damage = 0
if poison then
-- Add poison damage * probability of poisoning
poison_damage = wesnoth.game_config.poison_amount*(1-((1-defense)^attack.number))
end
if (not best_attack) or (attack_damage+poison_damage > best_damage+best_poison_damage) then
best_damage = attack_damage
best_poison_damage = poison_damage
best_attack = attack
end
end
return best_attack, best_damage, best_poison_damage
end
-- Use cached information when possible: this is expensive
local analysis = {}
if not recruit_data.analyses then
recruit_data.analyses = {}
else
if recruit_data.analyses[enemy_type] then
analysis = recruit_data.analyses[enemy_type] or {}
end
end
if analysis[ally_type] then
return analysis[ally_type]
end
local unit = wesnoth.create_unit {
type = enemy_type,
random_traits = false,
name = "X",
random_gender = false
}
local can_poison = poisonable(unit) and (not unit:ability('regenerate'))
local flat_defense = unit:defense("Gt")
local best_defense = get_best_defense(unit)
local recruit = wesnoth.create_unit {
type = ally_type,
random_traits = false,
name = "X",
random_gender = false
}
local recruit_flat_defense = recruit:defense("Gt")
local recruit_best_defense = get_best_defense(recruit)
local can_poison_retaliation = poisonable(recruit) and (not recruit:ability('regenerate'))
best_flat_attack, best_flat_damage, flat_poison = get_best_attack(recruit, unit, flat_defense, recruit_best_defense, can_poison)
best_high_defense_attack, best_high_defense_damage, high_defense_poison = get_best_attack(recruit, unit, best_defense, recruit_flat_defense, can_poison)
best_retaliation, best_retaliation_damage, retaliation_poison = get_best_attack(unit, recruit, recruit_flat_defense, best_defense, can_poison_retaliation)
local result = {
offense = { attack = best_flat_attack, damage = best_flat_damage, poison_damage = flat_poison },
defense = { attack = best_high_defense_attack, damage = best_high_defense_damage, poison_damage = high_defense_poison },
retaliation = { attack = best_retaliation, damage = best_retaliation_damage, poison_damage = retaliation_poison }
}
analysis[ally_type] = result
-- Cache result before returning
recruit_data.analyses[enemy_type] = analysis
return analysis[ally_type]
end
function can_slow(unit)
local attacks = unit.attacks
for i_a = 1,#attacks do
for _,sp in ipairs(attacks[i_a].specials) do
if (sp[1] == 'slow') then
return true
end
end
end
return false
end
function get_hp_ratio_with_gold()
function sum_gold_for_sides(side_filter)
-- sum positive amounts of gold for a set of sides
-- positive only because it is used to estimate the number of enemy units that could appear
-- and negative numbers shouldn't subtract from the number of units on the map
local gold = 0
local sides = wesnoth.get_sides(side_filter)
for i,s in ipairs(sides) do
if s.gold > 0 then
gold = gold + s.gold
end
end
return gold
end
-- Hitpoint ratio of own units / enemy units
-- Also convert available gold to a hp estimate
my_units = AH.get_live_units {
{ "filter_side", {{"allied_with", {side = wesnoth.current.side} }} }
}
enemies = AH.get_live_units {
{ "filter_side", {{"enemy_of", {side = wesnoth.current.side} }} }
}
local my_hp, enemy_hp = 0, 0
for i,u in ipairs(my_units) do my_hp = my_hp + u.hitpoints end
for i,u in ipairs(enemies) do enemy_hp = enemy_hp + u.hitpoints end
my_hp = my_hp + sum_gold_for_sides({{"allied_with", {side = wesnoth.current.side} }})*2.3
enemy_hp = enemy_hp+sum_gold_for_sides({{"enemy_of", {side = wesnoth.current.side} }})*2.3
hp_ratio = my_hp/(enemy_hp + 1e-6)
return hp_ratio
end
function do_recruit_eval(data)
-- Check if leader is on keep
local leader = wesnoth.get_units { side = wesnoth.current.side, canrecruit = 'yes' }[1]
if (not leader) or (not wesnoth.get_terrain_info(wesnoth.get_terrain(leader.x, leader.y)).keep) then
return 0
end
-- Check if there is enough gold to recruit a unit
local cheapest_unit_cost = AH.get_cheapest_recruit_cost()
if cheapest_unit_cost > wesnoth.sides[wesnoth.current.side].gold then
return 0
end
-- Check for space to recruit a unit
get_current_castle(leader, data)
local no_space = true
for i,c in ipairs(data.castle.locs) do
local unit = wesnoth.get_unit(c[1], c[2])
if (not AH.is_visible_unit(wesnoth.current.side, unit)) then
no_space = false
break
end
end
if no_space then
return 0
end
-- Check for minimal recruit option
if wesnoth.current.turn == 1 and params.min_turn_1_recruit and params.min_turn_1_recruit() then
if not get_village_target(leader, data)[1] then
return 0
end
end
if not data.recruit then
data.recruit = init_data(leader)
end
data.recruit.cheapest_unit_cost = cheapest_unit_cost
local score = 180010 -- default score if one not provided, just above RCA AI recruiting
if params.score_function then
score = params.score_function()
end
return score
end
function init_data(leader)
local data = {}
-- Count enemies of each type
local enemies = AH.get_live_units {
{ "filter_side", {{"enemy_of", {side = wesnoth.current.side} }}}
}
local enemy_counts = {}
local enemy_types = {}
local possible_enemy_recruit_count = 0
local function add_unit_type(unit_type)
if not enemy_counts[unit_type] then
table.insert(enemy_types, unit_type)
enemy_counts[unit_type] = 1
else
enemy_counts[unit_type] = enemy_counts[unit_type] + 1
end
end
-- Collect all enemies on map
for i, unit in ipairs(enemies) do
add_unit_type(unit.type)
end
-- Collect all possible enemy recruits and count them as virtual enemies
local enemy_sides = wesnoth.get_sides({
{ "enemy_of", {side = wesnoth.current.side} },
{ "has_unit", { canrecruit = true }} })
for i, side in ipairs(enemy_sides) do
possible_enemy_recruit_count = possible_enemy_recruit_count + #(wesnoth.sides[side.side].recruit)
for j, unit_type in ipairs(wesnoth.sides[side.side].recruit) do
add_unit_type(unit_type)
end
end
-- If no enemies were found, check params.enemy_types,
-- otherwise add a small number of "representative" unit types
if #enemy_types == 0 then
if params.enemy_types then
for _,enemy_type in ipairs(params.enemy_types) do
add_unit_type(enemy_type)
end
else
add_unit_type('Orcish Grunt')
add_unit_type('Orcish Archer')
add_unit_type('Wolf Rider')
add_unit_type('Spearman')
add_unit_type('Bowman')
add_unit_type('Cavalryman')
end
end
data.enemy_counts = enemy_counts
data.enemy_types = enemy_types
data.num_enemies = math.max(#enemies, 1)
data.possible_enemy_recruit_count = possible_enemy_recruit_count
return data
end
function ai_cas:recruit_rushers_eval()
local start_time, ca_name = wesnoth.get_time_stamp() / 1000., 'recruit_rushers'
if AH.print_eval() then AH.print_ts(' - Evaluating recruit_rushers CA:') end
local score = do_recruit_eval(recruit_data)
if score == 0 then
-- We're done for the turn, discard data
recruit_data.recruit = nil
end
if AH.print_eval() then AH.done_eval_messages(start_time, ca_name) end
return score
end
function ai_cas:recruit_rushers_exec()
if AH.print_exec() then AH.print_ts(' Executing recruit_rushers CA') end
if AH.show_messages() then wesnoth.wml_actions.message { speaker = 'narrator', message = 'Recruiting' } end
local enemy_counts = recruit_data.recruit.enemy_counts
local enemy_types = recruit_data.recruit.enemy_types
local num_enemies = recruit_data.recruit.num_enemies
local hp_ratio = get_hp_ratio_with_gold()
-- Determine effectiveness of recruitable units against each enemy unit type
local recruit_effectiveness = {}
local recruit_vulnerability = {}
local attack_type_count = {} -- The number of units who will likely use a given attack type
local attack_range_count = {} -- The number of units who will likely use a given attack range
local unit_attack_type_count = {} -- The attack types a unit will use
local unit_attack_range_count = {} -- The ranges a unit will use
local enemy_type_count = 0
local poisoner_count = 0.1 -- Number of units with a poison attack (set to slightly > 0 because we divide by it later)
local poisonable_count = 0 -- Number of units that the opponents control that are hurt by poison
local recruit_count = {}
for i, recruit_id in ipairs(wesnoth.sides[wesnoth.current.side].recruit) do
recruit_count[recruit_id] = #(AH.get_live_units { side = wesnoth.current.side, type = recruit_id, canrecruit = 'no' })
end
for i, unit_type in ipairs(enemy_types) do
enemy_type_count = enemy_type_count + 1
local poison_vulnerable = false
for i, recruit_id in ipairs(wesnoth.sides[wesnoth.current.side].recruit) do
local analysis = analyze_enemy_unit(unit_type, recruit_id)
if not recruit_effectiveness[recruit_id] then
recruit_effectiveness[recruit_id] = {damage = 0, poison_damage = 0}
recruit_vulnerability[recruit_id] = 0
end
recruit_effectiveness[recruit_id].damage = recruit_effectiveness[recruit_id].damage + analysis.defense.damage * enemy_counts[unit_type]^2
if analysis.defense.poison_damage and analysis.defense.poison_damage > 0 then
poison_vulnerable = true
recruit_effectiveness[recruit_id].poison_damage = recruit_effectiveness[recruit_id].poison_damage +
analysis.defense.poison_damage * enemy_counts[unit_type]^2
end
recruit_vulnerability[recruit_id] = recruit_vulnerability[recruit_id] + (analysis.retaliation.damage * enemy_counts[unit_type])^3
local attack_type = analysis.defense.attack.type
if not attack_type_count[attack_type] then
attack_type_count[attack_type] = 0
end
attack_type_count[attack_type] = attack_type_count[attack_type] + recruit_count[recruit_id]
local attack_range = analysis.defense.attack.range
if not attack_range_count[attack_range] then
attack_range_count[attack_range] = 0
end
attack_range_count[attack_range] = attack_range_count[attack_range] + recruit_count[recruit_id]
if not unit_attack_type_count[recruit_id] then
unit_attack_type_count[recruit_id] = {}
end
unit_attack_type_count[recruit_id][attack_type] = true
if not unit_attack_range_count[recruit_id] then
unit_attack_range_count[recruit_id] = {}
end
unit_attack_range_count[recruit_id][attack_range] = true
end
if poison_vulnerable then
poisonable_count = poisonable_count + enemy_counts[unit_type]
end
end
for i, recruit_id in ipairs(wesnoth.sides[wesnoth.current.side].recruit) do
-- Count the number of units with the poison ability
-- This could be wrong if all the units on the enemy side are immune to poison, but since poison has no effect then anyway it doesn't matter
if recruit_effectiveness[recruit_id].poison_damage > 0 then
poisoner_count = poisoner_count + recruit_count[recruit_id]
end
end
-- Subtract the number of possible recruits for the enemy from the list of poisonable units
-- This works perfectly unless some of the enemy recruits cannot be poisoned.
-- However, there is no problem with this since poison is generally less useful in such situations and subtracting them too discourages such recruiting
local poison_modifier = math.max(0, math.min(((poisonable_count-recruit_data.recruit.possible_enemy_recruit_count) / (poisoner_count*5)), 1))^2
for i, recruit_id in ipairs(wesnoth.sides[wesnoth.current.side].recruit) do
-- Ensure effectiveness and vulnerability are positive.
-- Negative values imply that drain is involved and the amount drained is very high
if recruit_effectiveness[recruit_id].damage <= 0 then
recruit_effectiveness[recruit_id].damage = 0.01
else
recruit_effectiveness[recruit_id].damage = (recruit_effectiveness[recruit_id].damage / (num_enemies)^2)^0.5
end
recruit_effectiveness[recruit_id].poison_damage = (recruit_effectiveness[recruit_id].poison_damage / (num_enemies)^2)^0.5 * poison_modifier
if recruit_vulnerability[recruit_id] <= 0 then
recruit_vulnerability[recruit_id] = 0.01
else
recruit_vulnerability[recruit_id] = (recruit_vulnerability[recruit_id] / ((num_enemies)^2))^0.5
end
end
-- Correct count of units for each range
local most_common_range
local most_common_range_count = 0
for range, count in pairs(attack_range_count) do
attack_range_count[range] = count/enemy_type_count
if attack_range_count[range] > most_common_range_count then
most_common_range = range
most_common_range_count = attack_range_count[range]
end
end
-- Correct count of units for each attack type
for attack_type, count in pairs(attack_type_count) do
attack_type_count[attack_type] = count/enemy_type_count
end
local recruit_type
local leader = wesnoth.get_units { side = wesnoth.current.side, canrecruit = 'yes' }[1]
repeat
recruit_data.recruit.best_hex, recruit_data.recruit.target_hex = ai_cas:find_best_recruit_hex(leader, recruit_data)
recruit_type = ai_cas:find_best_recruit(attack_type_count, unit_attack_type_count, recruit_effectiveness, recruit_vulnerability, attack_range_count, unit_attack_range_count, most_common_range_count)
until recruit_type
if wesnoth.unit_types[recruit_type].cost <= wesnoth.sides[wesnoth.current.side].gold then
AH.checked_recruit(ai, recruit_type, recruit_data.recruit.best_hex[1], recruit_data.recruit.best_hex[2])
-- If the recruited unit cannot reach the target hex, return it to the pool of targets
if recruit_data.recruit.target_hex and recruit_data.recruit.target_hex[1] then
local unit = wesnoth.get_unit(recruit_data.recruit.best_hex[1], recruit_data.recruit.best_hex[2])
local path, cost = wesnoth.find_path(unit, recruit_data.recruit.target_hex[1], recruit_data.recruit.target_hex[2], {viewing_side=0, max_cost=unit.max_moves+1})
if cost > unit.max_moves then
-- The last village added to the list should be the one we tried to aim for, check anyway
local last = #recruit_data.castle.assigned_villages_x
if (recruit_data.castle.assigned_villages_x[last] == recruit_data.recruit.target_hex[1]) and (recruit_data.castle.assigned_villages_y[last] == recruit_data.recruit.target_hex[2]) then
table.remove(recruit_data.castle.assigned_villages_x)
table.remove(recruit_data.castle.assigned_villages_y)
end
end
end
return true
else
-- This results in the CA being blacklisted -> clear cache
recruit_data.recruit = nil
return false
end
end
function get_current_castle(leader, data)
if (not data.castle) or (data.castle.x ~= leader.x) or (data.castle.y ~= leader.y) then
data.castle = {
locs = AH.get_locations_no_borders {
{ "filter_vision", { side = wesnoth.current.side, visible = 'yes' } },
{ "and", {
x = leader.x, y = leader.y, radius = 200,
{ "filter_radius", { terrain = 'C*,K*,C*^*,K*^*,*^K*,*^C*' } }
}}
},
x = leader.x,
y = leader.y
}
end
end
function ai_cas:find_best_recruit_hex(leader, data)
-- Find the best recruit hex
-- First choice: a hex that can reach an unowned village
-- Second choice: a hex close to the enemy
get_current_castle(leader, data)
local best_hex, village = get_village_target(leader, data)
if village[1] then
table.insert(data.castle.assigned_villages_x, village[1])
table.insert(data.castle.assigned_villages_y, village[2])
else
-- no available village, look for hex closest to enemy leader
-- and also the closest enemy
local max_rating = -1
local enemy_leaders = AH.get_attackable_enemies { canrecruit = 'yes' }
local closest_enemy = AH.get_closest_enemy()
for i,c in ipairs(data.castle.locs) do
local rating = 0
local unit = wesnoth.get_unit(c[1], c[2])
if (not AH.is_visible_unit(wesnoth.current.side, unit)) then
for j,e in ipairs(enemy_leaders) do
rating = rating + 1 / M.distance_between(c[1], c[2], e.x, e.y) ^ 2.
end
if closest_enemy then
rating = rating + 1 / M.distance_between(c[1], c[2], closest_enemy.x, closest_enemy.y) ^ 2.
end
if (rating > max_rating) then
max_rating, best_hex = rating, { c[1], c[2] }
end
end
end
end
if AH.print_eval() then
if village[1] then
std_print("Recruit at: " .. best_hex[1] .. "," .. best_hex[2] .. " -> " .. village[1] .. "," .. village[2])
else
std_print("Recruit at: " .. best_hex[1] .. "," .. best_hex[2])
end
end
return best_hex, village
end
function ai_cas:find_best_recruit(attack_type_count, unit_attack_type_count, recruit_effectiveness, recruit_vulnerability, attack_range_count, unit_attack_range_count, most_common_range_count)
-- Find best recruit based on damage done to enemies present, speed, and hp/gold ratio
local recruit_scores = {}
local best_scores = {offense = 0, defense = 0, move = 0}
local best_hex = recruit_data.recruit.best_hex
local target_hex = recruit_data.recruit.target_hex
local reference_hex = target_hex[1] and target_hex or best_hex
local enemy_location, distance_to_enemy = AH.get_closest_enemy(reference_hex, wesnoth.current.side, { viewing_side = 0 })
-- If no enemy is on the map, then we first use closest enemy start hex,
-- and if that does not exist either, a location mirrored w.r.t the center of the map
if not enemy_location then
local enemy_sides = wesnoth.get_sides({ { "enemy_of", {side = wesnoth.current.side} } })
local min_dist = math.huge
for _, side in ipairs(enemy_sides) do
local enemy_start_hex = wesnoth.special_locations[side.side]
if enemy_start_hex then
local dist = wesnoth.map.distance_between(reference_hex[1], reference_hex[2], enemy_start_hex[1], enemy_start_hex[2])
if dist < min_dist then
min_dist = dist
enemy_location = { x = enemy_start_hex[1], y = enemy_start_hex[2] }
end
end
end
if not enemy_location then
local width, height = wesnoth.get_map_size()
enemy_location = { x = width + 1 - reference_hex[1], y = height + 1 - reference_hex[2] }
end
distance_to_enemy = wesnoth.map.distance_between(reference_hex[1], reference_hex[2], enemy_location.x, enemy_location.y)
end
local gold_limit = math.huge
if recruit_data.castle.loose_gold_limit >= recruit_data.recruit.cheapest_unit_cost then
gold_limit = recruit_data.castle.loose_gold_limit
end
local recruitable_units = {}
for i, recruit_id in ipairs(wesnoth.sides[wesnoth.current.side].recruit) do
-- Count number of units with the same attack type. Used to avoid recruiting too many of the same unit
local attack_types = 0
local recruit_count = 0
for attack_type, count in pairs(unit_attack_type_count[recruit_id]) do
attack_types = attack_types + 1
recruit_count = recruit_count + attack_type_count[attack_type]
end
recruit_count = recruit_count / attack_types
local recruit_modifier = 1+recruit_count/50
local efficiency_index = 1
local unit_cost = wesnoth.unit_types[recruit_id].cost
-- Use time to enemy to encourage recruiting fast units when the opponent is far away (game is beginning or we're winning)
-- Base distance on
local recruit_unit = wesnoth.create_unit {
type = recruit_id,
x = best_hex[1],
y = best_hex[2],
random_traits = false,
name = "X",
random_gender = false
}
if target_hex[1] then
local path, cost = wesnoth.find_path(recruit_unit, target_hex[1], target_hex[2], {viewing_side=0, max_cost=wesnoth.unit_types[recruit_id].max_moves+1})
if cost > wesnoth.unit_types[recruit_id].max_moves then
-- Unit cost is effectively higher if cannot reach the village
efficiency_index = 2
unit_cost = no_village_cost(recruit_id)
end
-- Later calculations are based on where the unit will be after initial move
recruit_unit.x = target_hex[1]
recruit_unit.y = target_hex[2]
end
local path, cost = wesnoth.find_path(recruit_unit, enemy_location.x, enemy_location.y, {ignore_units = true})
local time_to_enemy = cost / wesnoth.unit_types[recruit_id].max_moves
local move_score = 1 / (time_to_enemy * unit_cost^0.5)
local eta = math.ceil(time_to_enemy)
if target_hex[1] then
-- expect a 1 turn delay to reach village
eta = eta + 1
end
-- divide the lawful bonus by eta before running it through the function because the function converts from 0 centered to 1 centered
local lawful_bonus = 0
local eta_turn = wesnoth.current.turn + eta
if eta_turn <= wesnoth.game_config.last_turn then
lawful_bonus = wesnoth.get_time_of_day(wesnoth.current.turn + eta).lawful_bonus / eta^2
end
local damage_bonus = AH.get_unit_time_of_day_bonus(recruit_unit.__cfg.alignment, lawful_bonus)
-- Estimate effectiveness on offense and defense
local offense_score =
(recruit_effectiveness[recruit_id].damage*damage_bonus+recruit_effectiveness[recruit_id].poison_damage)
/(wesnoth.unit_types[recruit_id].cost^0.3*recruit_modifier^4)
local defense_score = efficiency[recruit_id][efficiency_index]/recruit_vulnerability[recruit_id]
local unit_score = {offense = offense_score, defense = defense_score, move = move_score}
recruit_scores[recruit_id] = unit_score
for key, score in pairs(unit_score) do
if score > best_scores[key] then
best_scores[key] = score
end
end
if can_slow(recruit_unit) then
unit_score["slows"] = true
end
if recruit_unit:matches { ability = "healing" } then
unit_score["heals"] = true
end
if recruit_unit:matches { ability = "skirmisher" } then
unit_score["skirmisher"] = true
end
recruitable_units[recruit_id] = recruit_unit
end
local healer_count, healable_count = get_unit_counts_for_healing()
local best_score = 0
local recruit_type
local offense_weight = 2.5
local defense_weight = 1/hp_ratio^0.5
local move_weight = math.max((distance_to_enemy/20)^2, 0.25)
local randomness = params.randomness or 0.1
-- Bonus for higher-level units, as unit cost is penalized otherwise
local high_level_fraction = params.high_level_fraction or 0
local all_units = AH.get_live_units {
side = wesnoth.current.side,
{ "not", { canrecruit = "yes" }}
}
local level_count = {}
for _,unit in ipairs(all_units) do
local level = unit.level
level_count[level] = (level_count[level] or 0) + 1
end
local min_recruit_level, max_recruit_level = math.huge, -math.huge
for i, recruit_id in ipairs(wesnoth.sides[wesnoth.current.side].recruit) do
local level = wesnoth.unit_types[recruit_id].level
if (level < min_recruit_level) then min_recruit_level = level end
if (level > max_recruit_level) then max_recruit_level = level end
end
if (min_recruit_level < 1) then min_recruit_level = 1 end
local unit_deficit = {}
for i=min_recruit_level+1,max_recruit_level do
-- If no non-leader units are on the map yet, we set up the situation as if there were
-- one of each level. This is in order to get the situation for the first recruit right.
local n_units = #all_units
local n_units_this_level = level_count[i] or 0
if (n_units == 0) then
n_units = max_recruit_level - min_recruit_level
n_units_this_level = 1
end
unit_deficit[i] = high_level_fraction ^ (i - min_recruit_level) * n_units - n_units_this_level
end
for i, recruit_id in ipairs(wesnoth.sides[wesnoth.current.side].recruit) do
local level_bonus = 0
local level = wesnoth.unit_types[recruit_id].level
if (level > min_recruit_level) and (unit_deficit[level] > 0) then
level_bonus = 0.25 * unit_deficit[level]^2
end
local scores = recruit_scores[recruit_id]
local offense_score = (scores["offense"]/best_scores["offense"])^0.5
local defense_score = (scores["defense"]/best_scores["defense"])^0.5
local move_score = (scores["move"]/best_scores["move"])^0.5
local bonus = math.random()*randomness
if scores["slows"] then
bonus = bonus + 0.4
end
if scores["heals"] then
bonus = bonus + (healable_count/(healer_count+1))/20
end
if scores["skirmisher"] then
bonus = bonus + 0.1
end
for attack_range, count in pairs(unit_attack_range_count[recruit_id]) do
bonus = bonus + 0.02 * most_common_range_count / (attack_range_count[attack_range]+1)
end
local race = wesnoth.races[wesnoth.unit_types[recruit_id].__cfg.race]
local num_traits = race and race.num_traits or 0
bonus = bonus + 0.03 * num_traits^2
if target_hex[1] then
recruitable_units[recruit_id].x = best_hex[1]
recruitable_units[recruit_id].y = best_hex[2]
local path, cost = wesnoth.find_path(recruitable_units[recruit_id], target_hex[1], target_hex[2], {viewing_side=0, max_cost=wesnoth.unit_types[recruit_id].max_moves+1})
if cost > wesnoth.unit_types[recruit_id].max_moves then
-- penalty if the unit can't reach the target village
bonus = bonus - 0.2
end
end
local score = offense_score*offense_weight + defense_score*defense_weight + move_score*move_weight + bonus + level_bonus
if AH.print_eval() then
std_print(recruit_id .. " score: " .. offense_score*offense_weight .. " + " .. defense_score*defense_weight .. " + " .. move_score*move_weight .. " + " .. bonus .. " + " .. level_bonus .. " = " .. score)
end
if score > best_score and wesnoth.unit_types[recruit_id].cost <= gold_limit then
best_score = score
recruit_type = recruit_id
end
end
return recruit_type
end
function get_unit_counts_for_healing()
local healers = #AH.get_live_units {
side = wesnoth.current.side,
ability = "healing",
{ "not", { canrecruit = "yes" }}
}
local healable = #AH.get_live_units {
side = wesnoth.current.side,
{ "not", { ability = "regenerates" }}
}
return healers, healable
end
function get_village_target(leader, data)
-- Only consider villages reachable by our fastest unit
local fastest_unit_speed = 0
for i, recruit_id in ipairs(wesnoth.sides[wesnoth.current.side].recruit) do
if wesnoth.unit_types[recruit_id].max_moves > fastest_unit_speed then
fastest_unit_speed = wesnoth.unit_types[recruit_id].max_moves
end
end
-- get a list of all unowned and enemy-owned villages within fastest_unit_speed
-- this may have false positives (villages that can't be reached due to difficult/impassible terrain)
local exclude_map = LS.create()
if data.castle.assigned_villages_x and data.castle.assigned_villages_x[1] then
for i,x in ipairs(data.castle.assigned_villages_x) do
exclude_map:insert(x, data.castle.assigned_villages_y[i])
end
end
local all_villages = wesnoth.get_villages()
local villages = {}
for _,v in ipairs(all_villages) do
local owner = wesnoth.get_village_owner(v[1], v[2])
if ((not owner) or wesnoth.is_enemy(owner, wesnoth.current.side))
and (not exclude_map:get(v[1], v[2]))
then
for _,loc in ipairs(data.castle.locs) do
local dist = M.distance_between(v[1], v[2], loc[1], loc[2])
if (dist <= fastest_unit_speed) then
table.insert(villages, v)
break
end
end
end
end
local hex, target, shortest_distance = {}, {}, AH.no_path
if not data.castle.assigned_villages_x then
data.castle.assigned_villages_x = {}
data.castle.assigned_villages_y = {}
if not ai.aspects.passive_leader and (not params.leader_takes_village or params.leader_takes_village()) then
-- skip one village for the leader
for i,v in ipairs(villages) do
local path, cost = wesnoth.find_path(leader, v[1], v[2], {max_cost = leader.max_moves+1})
if cost <= leader.max_moves then
table.insert(data.castle.assigned_villages_x, v[1])
table.insert(data.castle.assigned_villages_y, v[2])
table.remove(villages, i)
break
end
end
end
end
local village_count = #villages
local test_units = get_test_units()
local num_recruits = #test_units
local total_village_distance = {}
for j,c in ipairs(data.castle.locs) do
c_index = c[1] + c[2]*1000
total_village_distance[c_index] = 0
for i,v in ipairs(villages) do
total_village_distance[c_index] = total_village_distance[c_index] + M.distance_between(c[1], c[2], v[1], v[2])
end
end
local width,height,border = wesnoth.get_map_size()
if (not recruit_data.unit_distances) then recruit_data.unit_distances = {} end
for i,v in ipairs(villages) do
local close_castle_hexes = {}
for _,loc in ipairs(data.castle.locs) do
local dist = M.distance_between(v[1], v[2], loc[1], loc[2])
if (dist <= fastest_unit_speed) then
if (not wesnoth.get_unit(loc[1], loc[2])) then
table.insert(close_castle_hexes, loc)
end
end
end
for u,unit in ipairs(test_units) do
test_units[u].x = v[1]
test_units[u].y = v[2]
end
local viable_village = false
local village_best_hex, village_shortest_distance = {}, AH.no_path
for j,c in ipairs(close_castle_hexes) do
if c[1] > 0 and c[2] > 0 and c[1] <= width and c[2] <= height then
local distance = 0
for x,unit in ipairs(test_units) do
local key = unit.type .. '_' .. v[1] .. '-' .. v[2] .. '_' .. c[1] .. '-' .. c[2]
local path, unit_distance
if (not recruit_data.unit_distances[key]) then
path, unit_distance = wesnoth.find_path(unit, c[1], c[2], {viewing_side=0, max_cost=fastest_unit_speed+1})
recruit_data.unit_distances[key] = unit_distance
else
unit_distance = recruit_data.unit_distances[key]
end
distance = distance + unit_distance
-- Village is only viable if at least one unit can reach it
if unit_distance <= unit.max_moves then
viable_village = true
end
end
distance = distance / num_recruits
if distance < village_shortest_distance
or (distance == village_shortest_distance and distance < AH.no_path
and total_village_distance[c[1] + c[2]*1000] > total_village_distance[village_best_hex[1]+village_best_hex[2]*1000])
then
village_best_hex = c
village_shortest_distance = distance
end
end
end
if village_shortest_distance < shortest_distance then
hex = village_best_hex
target = v
shortest_distance = village_shortest_distance
end
if not viable_village then
-- this village could not be reached by any unit
-- eliminate it from consideration
table.insert(data.castle.assigned_villages_x, v[1])
table.insert(data.castle.assigned_villages_y, v[2])
village_count = village_count - 1
end
end
data.castle.loose_gold_limit = math.floor(wesnoth.sides[wesnoth.current.side].gold/village_count + 0.5)
return hex, target
end
function get_test_units()
local test_units, num_recruits = {}, 0
local movetypes = {}
for x,id in ipairs(wesnoth.sides[wesnoth.current.side].recruit) do
local custom_movement = wml.get_child(wesnoth.unit_types[id].__cfg, "movement_costs")
local movetype = wesnoth.unit_types[id].__cfg.movement_type
if custom_movement
or (not movetypes[movetype])
or (movetypes[movetype] < wesnoth.unit_types[id].max_moves)
then
if not custom_movement then
movetypes[movetype] = wesnoth.unit_types[id].max_moves
end
num_recruits = num_recruits + 1
test_units[num_recruits] = wesnoth.create_unit({
type = id,
side = wesnoth.current.side,
random_traits = false,
name = "X",
random_gender = false
})
end
end
return test_units
end
end -- init()
}