Fast Micro AI: add support for [avoid] tags

This can either be an [avoid] tag inside the [micro_ai] tag itself, or
the [avoid] tag of the default AI (e.g. as defined in the side
definition).  If both are given, the former has priority.

data/ai/micro_ais/cas/ca_fast_attack_utils.lua

@@ -1,5 +1,6 @@
 local H = wesnoth.require "lua/helper.lua"
 local AH = wesnoth.require "ai/lua/ai_helper.lua"
+local LS = wesnoth.require "lua/location_set.lua"
 
 -- Functions to perform fast evaluation of attacks and attack combinations.
 -- The emphasis with all of this is on speed, not elegance.
@@ -14,6 +15,37 @@ local AH = wesnoth.require "ai/lua/ai_helper.lua"
 
 local ca_fast_attack_utils = {}
 
+function ca_fast_attack_utils.get_avoid_map(cfg)
+    -- Get map of locations to be avoided.
+    -- Use [micro_ai][avoid] tag with priority over [ai][avoid].
+    -- If neither is given, return an empty location set.
+    -- Note that ai.get_avoid() cannot be used as it always returns an array,
+    -- even when the aspect is not set, and an empty array could also mean that
+    -- no hexes match the filter
+
+    local avoid_tag
+
+    if cfg.avoid then
+        avoid_tag = cfg.avoid
+    else
+        local ai_tag = H.get_child(wesnoth.sides[wesnoth.current.side].__cfg, 'ai')
+        for aspect in H.child_range(ai_tag, 'aspect') do
+            if (aspect.id == 'avoid') then
+                local facet = H.get_child(aspect, 'facet')
+                if facet then
+                    avoid_tag = H.get_child(facet, 'value')
+                end
+            end
+        end
+    end
+
+    if avoid_tag then
+        return LS.of_pairs(wesnoth.get_locations(avoid_tag))
+    else
+        return LS.create()
+    end
+end
+
 function ca_fast_attack_utils.gamedata_setup()
     -- Keep game data in a table for faster access.
     -- This is currently re-done on every move. Could be optimized by only

data/ai/micro_ais/cas/ca_fast_combat.lua

@@ -54,6 +54,9 @@ function ca_fast_combat:evaluation(ai, cfg, self)
     if (aggression > 1) then aggression = 1 end
     local own_value_weight = 1. - aggression
 
+    -- Get the locations to be avoided
+    local avoid_map = FAU.get_avoid_map(cfg)
+
     for i = #self.data.fast_combat_units,1,-1 do
         local unit = self.data.fast_combat_units[i]
         local unit_info = FAU.get_unit_info(unit, self.data.gamedata)
@@ -65,7 +68,9 @@ function ca_fast_combat:evaluation(ai, cfg, self)
             if (#attacks > 0) then
                 local max_rating, best_target, best_dst = -9e99
                 for _,attack in ipairs(attacks) do
-                    if (not excluded_enemies_map:get(attack.target.x, attack.target.y)) then
+                    if (not excluded_enemies_map:get(attack.target.x, attack.target.y))
+                        and (not avoid_map:get(attack.dst.x, attack.dst.y))
+                    then
                         local target = wesnoth.get_unit(attack.target.x, attack.target.y)
                         local target_info = FAU.get_unit_info(target, self.data.gamedata)
 

data/ai/micro_ais/cas/ca_fast_move.lua

@@ -1,5 +1,6 @@
 local H = wesnoth.require "lua/helper.lua"
 local AH = wesnoth.require "ai/lua/ai_helper.lua"
+local FAU = wesnoth.require "ai/micro_ais/cas/ca_fast_attack_utils.lua"
 
 local ca_fast_move = {}
 
@@ -14,6 +15,9 @@ function ca_fast_move:execution(ai, cfg, self)
     local move_cost_factor = cfg.move_cost_factor or 2.0
     if (move_cost_factor < 1.1) then move_cost_factor = 1.1 end
 
+    -- Get the locations to be avoided
+    local avoid_map = FAU.get_avoid_map(cfg)
+
     local all_units_MP = AH.get_units_with_moves { side = wesnoth.current.side, canrecruit = 'no' }
     local units = {}
     for _,unit in ipairs(all_units_MP) do
@@ -29,16 +33,18 @@ function ca_fast_move:execution(ai, cfg, self)
     if leader and (village_value > 0) then
         local villages = wesnoth.get_villages()
 
-        -- Eliminate villages owned by a side that is not an enemy
+        -- Eliminate villages in avoid_map and those owned by an allied side
         -- Also remove unowned villages if the AI has no leader
         for i = #villages,1,-1 do
-            local owner = wesnoth.get_village_owner(villages[i][1], villages[i][2])
-            if owner and (not wesnoth.is_enemy(owner, wesnoth.current.side)) then
-                table.remove(villages, i)
-            end
-
-            if (not leader) and (not owner) then
+            if avoid_map:get(villages[i][1], villages[i][2]) then
                 table.remove(villages, i)
+            else
+                local owner = wesnoth.get_village_owner(villages[i][1], villages[i][2])
+                if owner and (not wesnoth.is_enemy(owner, wesnoth.current.side)) then
+                    table.remove(villages, i)
+                elseif (not leader) and (not owner) then
+                    table.remove(villages, i)
+                end
             end
         end
 
@@ -110,8 +116,10 @@ function ca_fast_move:execution(ai, cfg, self)
     end
 
     for i_el,enemy_leader in ipairs(enemy_leaders) do
-        local goal = { x = enemy_leader.x, y = enemy_leader.y }
-        table.insert(goals, goal)
+        if (not avoid_map:get(enemy_leader.x, enemy_leader.y)) then
+            local goal = { x = enemy_leader.x, y = enemy_leader.y }
+            table.insert(goals, goal)
+        end
     end
 
     -- Putting information about all the units into the goals
@@ -196,35 +204,37 @@ function ca_fast_move:execution(ai, cfg, self)
             local pre_ratings = {}
             local max_rating, best_hex = -9e99
             for _,loc in ipairs(reach) do
-                local rating = - H.distance_between(loc[1], loc[2], short_goal[1], short_goal[2])
-                local other_rating = - H.distance_between(loc[1], loc[2], goal.x, goal.y) / 10.
-                rating = rating + other_rating
+                if (not avoid_map:get(loc[1], loc[2])) then
+                    local rating = - H.distance_between(loc[1], loc[2], short_goal[1], short_goal[2])
+                    local other_rating = - H.distance_between(loc[1], loc[2], goal.x, goal.y) / 10.
+                    rating = rating + other_rating
 
-                local unit_in_way
-                if (rating > max_rating) then
-                    unit_in_way = wesnoth.get_unit(loc[1], loc[2])
-                    if (unit_in_way == unit) then unit_in_way = nil end
-
-                    if unit_in_way and (unit_in_way.side == unit.side) then
-                        local reach = AH.get_reachable_unocc(unit_in_way)
-                        if (reach:size() > 1) then
-                            unit_in_way = nil
-                            rating = rating - 0.01
-                            other_rating = other_rating - 0.01
+                    local unit_in_way
+                    if (rating > max_rating) then
+                        unit_in_way = wesnoth.get_unit(loc[1], loc[2])
+                        if (unit_in_way == unit) then unit_in_way = nil end
+
+                        if unit_in_way and (unit_in_way.side == unit.side) then
+                            local reach = AH.get_reachable_unocc(unit_in_way)
+                            if (reach:size() > 1) then
+                                unit_in_way = nil
+                                rating = rating - 0.01
+                                other_rating = other_rating - 0.01
+                            end
                         end
                     end
-                end
 
-                if (not unit_in_way) then
-                    if cfg.dungeon_mode then
-                        table.insert(pre_ratings, {
-                            rating = rating,
-                            other_rating = other_rating,
-                            x = loc[1], y = loc[2]
-                        })
-                    else
-                        if (rating > max_rating) then
-                            max_rating, best_hex = rating, { loc[1], loc[2] }
+                    if (not unit_in_way) then
+                        if cfg.dungeon_mode then
+                            table.insert(pre_ratings, {
+                                rating = rating,
+                                other_rating = other_rating,
+                                x = loc[1], y = loc[2]
+                            })
+                        else
+                            if (rating > max_rating) then
+                                max_rating, best_hex = rating, { loc[1], loc[2] }
+                            end
                         end
                     end
                 end

data/ai/micro_ais/micro_ai_wml_tag.lua

@@ -460,7 +460,7 @@ function wesnoth.wml_actions.micro_ai(cfg)
 
     elseif (cfg.ai_type == 'fast_ai') then
         optional_keys = {
-            "attack_hidden_enemies", "dungeon_mode", "filter", "filter_second",
+            "attack_hidden_enemies", "avoid", "dungeon_mode", "filter", "filter_second",
             "include_occupied_attack_hexes", "leader_weight", "move_cost_factor",
             "weak_units_first", "skip_combat_ca", "skip_move_ca"
         }