Basic Zone mechanics working

maps/scrap_towny_ffa/exclusion_zone.lua

@@ -0,0 +1,81 @@
+local Public = {}
+
+local math_random = math.random
+local table_insert = table.insert
+local math_floor = math.floor
+local atan2 = math.atan2
+
+local Event = require 'utils.event'
+local ScenarioTable = require 'maps.scrap_towny_ffa.table'
+local Team = require 'maps.scrap_towny_ffa.team'
+local Building = require 'maps.scrap_towny_ffa.building'
+local Colors = require 'maps.scrap_towny_ffa.colors'
+local Enemy = require 'maps.scrap_towny_ffa.enemy'
+local Color = require 'utils.color_presets'
+local CommonFunctions = require 'utils.common'
+
+local zone_size = 80
+
+local function draw_borders(zone)
+    local surface = zone.surface
+    local right = zone.box.right_bottom.x
+    local left = zone.box.left_top.x
+    local top = zone.box.left_top.y
+    local bottom = zone.box.right_bottom.y
+    local beam_type = 'electric-beam-no-sound'
+    surface.create_entity({name = beam_type, position = {right, top},
+                           source = {right, top}, target = {right, bottom + 1}})    -- intentional offset here to correct visual appearance
+    surface.create_entity({name = beam_type, position = {right, bottom},
+                           source = {right, bottom}, target = {left, bottom}})
+    surface.create_entity({name = beam_type, position = {left, bottom},
+                           source = {left, bottom}, target = {left, top}})
+    surface.create_entity({name = beam_type, position = {left, top},
+                           source = {left, top}, target = {right, top}})
+end
+
+function Public.add_zone(surface, force, center)
+    local this = ScenarioTable.get_table()
+
+    -- Init zone geometry
+    local box = {left_top = {x = center.x - zone_size / 2, y = center.y - zone_size / 2},
+                right_bottom = {x = center.x + zone_size / 2, y = center.y + zone_size / 2}}
+    local zone = {surface = surface, force = force, center = center, box = box}
+
+    table_insert(this.exclusion_zones, zone)
+    draw_borders(zone)
+end
+
+local function vector_norm(vector)
+    return math.sqrt(vector.x ^ 2 + vector.y ^ 2)
+end
+
+local function on_player_changed_position(event)
+    --TODO: fast 1st level check: count_entities(beam) around zone_size?
+    local player = game.get_player(event.player_index)
+    local surface = player.surface
+    if not surface or not surface.valid then
+        return
+    end
+
+    local this = ScenarioTable.get_table()
+    for _, zone in pairs(this.exclusion_zones) do
+        if CommonFunctions.point_in_bounding_box(player.position, zone.box) then
+            local center_diff = { x = player.position.x - zone.center.x, y = player.position.y - zone.center.y}
+            center_diff.x = center_diff.x / vector_norm(center_diff)
+            center_diff.y = center_diff.y / vector_norm(center_diff)
+            player.teleport({ player.position.x + center_diff.x, player.position.y + center_diff.y}, surface)
+
+            if player.character then
+                player.character.health = player.character.health - 25
+                player.character.surface.create_entity({name = 'water-splash', position = player.position})
+                if player.character.health <= 0 then
+                    player.character.die('enemy')
+                end
+            end
+        end
+    end
+end
+
+Event.add(defines.events.on_player_changed_position, on_player_changed_position)
+
+return Public

maps/scrap_towny_ffa/table.lua

@@ -37,6 +37,7 @@ function Public.reset_table()
     this.mining_entity = {}
     this.mining_target = {}
     this.spaceships = {}
+    this.exclusion_zones = {}
 end
 
 function Public.get_table()

maps/scrap_towny_ffa/town_center.lua

@@ -13,6 +13,7 @@ local Building = require 'maps.scrap_towny_ffa.building'
 local Colors = require 'maps.scrap_towny_ffa.colors'
 local Enemy = require 'maps.scrap_towny_ffa.enemy'
 local Color = require 'utils.color_presets'
+local ExclusionZone = require 'maps.scrap_towny_ffa.exclusion_zone'
 
 local town_radius = 27
 local radius_between_towns = 64
@@ -181,6 +182,8 @@ local function draw_town_spawn(player_name)
         end
     end
 
+    ExclusionZone.add_zone(surface, force, position)
+
     -- ore patches
     local ores = {'iron-ore', 'copper-ore', 'stone', 'coal'}
     table_shuffle(ores)