-- Copyright (c) 2024 - Ognjen 'xolatile' Milan Robovic
--
-- GNU General Public Licence (version 3 or later)

with core, ui, attribute, skill, resource, equipment, unit, construction, chad, effect;

use type core.cursor_code;
use type core.signal_code;
use type core.point;

package body world is

------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

	view_reach : constant integer := 96;

	lake_count : constant natural := 6;

	landmark_limit     : constant integer := 480;
	location_limit     : constant integer := 240;
	construction_limit : constant natural := 120;
	equipment_limit    : constant natural := 300;
	unit_limit         : constant natural := 600;

	tiles : array (biome) of core.sprite;

	target : core.vector := (-1, -1);

	dark               : core.sprite;
	border_upper       : core.sprite;
	border_lower       : core.sprite;
	border_left        : core.sprite;
	border_right       : core.sprite;
	corner_upper_left  : core.sprite;
	corner_upper_right : core.sprite;
	corner_lower_left  : core.sprite;
	corner_lower_right : core.sprite;
	arrow_target       : core.sprite;
	arrow_upper        : core.sprite;
	arrow_lower        : core.sprite;
	arrow_left         : core.sprite;
	arrow_right        : core.sprite;
	arrow_upper_left   : core.sprite;
	arrow_upper_right  : core.sprite;
	arrow_lower_left   : core.sprite;
	arrow_lower_right  : core.sprite;

	draw_tiles_timer         : natural := 0;
	draw_views_timer         : natural := 0;
	draw_landmarks_timer     : natural := 0;
	draw_locations_timer     : natural := 0;
	draw_constructions_timer : natural := 0;
	draw_equipments_timer    : natural := 0;
	draw_units_timer         : natural := 0;
	draw_world_timer         : natural := 0;

	drawn_tiles         : natural := 0;
	drawn_views         : natural := 0;
	drawn_landmarks     : natural := 0;
	drawn_locations     : natural := 0;
	drawn_constructions : natural := 0;
	drawn_equipments    : natural := 0;
	drawn_units         : natural := 0;

                                             ------------------------------------------------------------------------------------------

	procedure generate_lake (x, y : in integer; size : in natural);

	procedure compute_world_visibility_grid (offset : in core.vector);
	procedure compute_world_frame           (offset : in core.vector);

	procedure draw_tiles         (offset, view_from, view_to : in core.vector);
	procedure draw_landmarks     (offset, view_from, view_to : in core.vector);
	procedure draw_locations     (offset, view_from, view_to : in core.vector);
	procedure draw_constructions (offset, view_from, view_to : in core.vector);
	procedure draw_equipments    (offset, view_from, view_to : in core.vector);
	procedure draw_units         (offset, view_from, view_to : in core.vector);
	procedure draw_alternative   (offset, view_from, view_to : in core.vector);

	procedure compute_earth_to_water_transition;

------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

	procedure configure is
	begin
		core.echo (core.comment, "Configuring world components...");
		--
		for index in biome loop
			tiles (index) := core.import_sprite (core.folder & "/game/world/terrain/" & core.lowercase (index'image) & ".png", 4, 1);
		end loop;
		--
		dark               := core.import_sprite (core.folder & "/game/world/dark.png",                     1, 1);
		border_upper       := core.import_sprite (core.folder & "/game/world/frame/border_upper.png",       1, 1);
		border_lower       := core.import_sprite (core.folder & "/game/world/frame/border_lower.png",       1, 1);
		border_left        := core.import_sprite (core.folder & "/game/world/frame/border_left.png",        1, 1);
		border_right       := core.import_sprite (core.folder & "/game/world/frame/border_right.png",       1, 1);
		corner_upper_left  := core.import_sprite (core.folder & "/game/world/frame/corner_upper_left.png",  1, 1);
		corner_upper_right := core.import_sprite (core.folder & "/game/world/frame/corner_upper_right.png", 1, 1);
		corner_lower_left  := core.import_sprite (core.folder & "/game/world/frame/corner_lower_left.png",  1, 1);
		corner_lower_right := core.import_sprite (core.folder & "/game/world/frame/corner_lower_right.png", 1, 1);
		arrow_target       := core.import_sprite (core.folder & "/game/world/arrow/target.png",             1, 1);
		arrow_upper        := core.import_sprite (core.folder & "/game/world/arrow/upper.png",              1, 1);
		arrow_lower        := core.import_sprite (core.folder & "/game/world/arrow/lower.png",              1, 1);
		arrow_left         := core.import_sprite (core.folder & "/game/world/arrow/left.png",               1, 1);
		arrow_right        := core.import_sprite (core.folder & "/game/world/arrow/right.png",              1, 1);
		arrow_upper_left   := core.import_sprite (core.folder & "/game/world/arrow/upper_left.png",         1, 1);
		arrow_upper_right  := core.import_sprite (core.folder & "/game/world/arrow/upper_right.png",        1, 1);
		arrow_lower_left   := core.import_sprite (core.folder & "/game/world/arrow/lower_left.png",         1, 1);
		arrow_lower_right  := core.import_sprite (core.folder & "/game/world/arrow/lower_right.png",        1, 1);
		--
		for index in landmark_index loop
			landmarks (index) := core.import_sprite (file_path => core.folder & "/game/world/landmark/" & core.lowercase (index'image) & ".png",
			                                         frames    => landmark_description (index).frames,
			                                         states    => 1);
		end loop;
		--
		for index in location_index loop
			locations (index) := core.import_sprite (file_path => core.folder & "/game/world/location/" & core.lowercase (index'image) & ".png",
			                                         frames    => location_description (index).frames,
			                                         states    => location_description (index).states);
		end loop;
	end configure;

                                             ------------------------------------------------------------------------------------------

	procedure make (index : in biome; width, height, chad_limit : in natural) is
	begin
		core.echo (core.comment, "-- Procedurally generating new map...");
		--
		core.echo (core.comment, "-- -- Map type       : " & index'image);
		core.echo (core.comment, "-- -- Map width      :"  & width'image);
		core.echo (core.comment, "-- -- Map height     :"  & height'image);
		core.echo (core.comment, "-- -- Landmark count :"  & landmark_limit'image);
		--
		map.kind       := index;
		map.width      := width;
		map.height     := height;
		map.chad_limit := chad_limit;
		map.chad_count := 0;
		--
		map.tiles         := new integer_matrix    (0 .. map.width - 1, 0 .. map.height - 1);
		map.clips         := new boolean_matrix    (0 .. map.width - 1, 0 .. map.height - 1);
		map.views         := new boolean_matrix    (0 .. map.width - 1, 0 .. map.height - 1);
		map.landmarks     := new entity_array      (1 .. landmark_limit);
		map.locations     := new entity_array      (1 .. location_limit);
		map.constructions := new entity_array      (1 .. construction_limit);
		map.equipments    := new entity_array      (1 .. equipment_limit);
		map.units         := new entity_array      (1 .. unit_limit);
		map.chads         := new chad.informations (1 .. map.chad_limit);
		--
		for x in 0 .. width - 1 loop
			for y in 0 .. height - 1 loop
				map.tiles (x, y) := (if core.random (0, 17) > 3 then core.random (0, 5) else core.random (0, 17));
				map.clips (x, y) := false;
				map.views (x, y) := false;
			end loop;
		end loop;
		--
		for this in 1 .. lake_count loop
			generate_lake (x    => core.random (23, map.width  - 23),
			               y    => core.random (23, map.height - 23),
			               size => core.random (7, 19));
		end loop;
		--
		compute_earth_to_water_transition;
		--
		for x in 0 .. width - 1 loop
			for y in 0 .. height - 1 loop
				if map.tiles (x, y) > 17 then
					map.clips (x, y) := true;
				end if;
			end loop;
		end loop;
		--
		for index in 1 .. landmark_limit loop
			map.landmarks (index).index := core.random (0, landmark_count - 1);
			map.landmarks (index).state := 0;
			<<repeat_landmark_generation>>
			map.landmarks (index).x     := core.random (6, map.width  - 6);
			map.landmarks (index).y     := core.random (6, map.height - 6);
			--
			if map.clips (map.landmarks (index).x, map.landmarks (index).y) then
				goto repeat_landmark_generation;
			end if;
			--
			if landmark_description (landmark_index'val (map.landmarks (index).index)).clip then
				declare reach_x : constant natural := landmarks (landmark_index'val (map.landmarks (index).index)).width  / core.base;
				        reach_y : constant natural := landmarks (landmark_index'val (map.landmarks (index).index)).height / core.base;
				begin
					for x in 0 .. reach_x - 1 loop
						for y in 0 .. reach_y - 1 loop
							map.clips (map.landmarks (index).x + x, map.landmarks (index).y + y) := true;
						end loop;
					end loop;
				end;
			end if;
		end loop;
		--
		for index in 1 .. location_limit loop
			map.locations (index).index := core.random (0, location_count - 1);
			map.locations (index).state := 0;
			<<repeat_location_generation>>
			map.locations (index).x     := core.random (6, map.width  - 6);
			map.locations (index).y     := core.random (6, map.height - 6);
			--
			if map.clips (map.locations (index).x, map.locations (index).y) then
				goto repeat_location_generation;
			end if;
			--
			if location_description (location_index'val (map.locations (index).index)).clip then
				declare reach_x : constant natural := locations (location_index'val (map.locations (index).index)).width  / core.base;
				        reach_y : constant natural := locations (location_index'val (map.locations (index).index)).height / core.base;
				begin
					for x in 0 .. reach_x - 1 loop
						for y in 0 .. reach_y - 1 loop
							map.clips (map.locations (index).x + x, map.locations (index).y + y) := true;
						end loop;
					end loop;
				end;
			end if;
		end loop;
		--
		for index in 1 .. construction_limit loop
			map.constructions (index).index := core.random (0, construction.count - 1);
			map.constructions (index).state := 0;
			<<repeat_construction_generation>>
			map.constructions (index).x     := core.random (6, map.width          - 6);
			map.constructions (index).y     := core.random (6, map.height         - 6);
			--
			if map.clips (map.constructions (index).x, map.constructions (index).y) then
				goto repeat_construction_generation;
			end if;
			--
			declare reach_x : constant natural := construction.sprite (construction.enumeration'val (map.constructions (index).index)).width  / core.base;
			        reach_y : constant natural := construction.sprite (construction.enumeration'val (map.constructions (index).index)).height / core.base;
			begin
				for x in 0 .. reach_x - 1 loop
					for y in 0 .. reach_y - 1 loop
						map.clips (map.constructions (index).x + x, map.constructions (index).y + y) := true;
					end loop;
				end loop;
			end;
		end loop;
		--
		for index in 1 .. equipment_limit loop
			map.equipments (index).index := core.random (0, equipment.count - 1);
			map.equipments (index).state := 0;
			<<repeat_equipment_generation>>
			map.equipments (index).x     := core.random (0, map.width  - 1);
			map.equipments (index).y     := core.random (0, map.height - 1);
			--
			if map.clips (map.equipments (index).x, map.equipments (index).y) then
				goto repeat_equipment_generation;
			end if;
		end loop;
		--
		for index in 1 .. unit_limit loop
			map.units (index).index := core.random (1, unit.count - 1);
			map.units (index).state := 0;
			<<repeat_unit_generation>>
			map.units (index).x     := core.random (0, map.width  - 1);
			map.units (index).y     := core.random (0, map.height - 1);
			--
			if map.clips (map.units (index).x, map.units (index).y) then
				goto repeat_unit_generation;
			end if;
			--
			map.clips (map.units (index).x, map.units (index).y) := true;
		end loop;
		--
		core.echo (core.success, "Finished procedurally generating new map.");
	end make;

                                             ------------------------------------------------------------------------------------------

	procedure save (file_name : in string) is
		procedure save_entity (here : in core.io.file_type; data : in entity_description) is
		begin
			core.io.write (here, data.index);
			core.io.write (here, data.state);
			core.io.write (here, data.x);
			core.io.write (here, data.y);
		end save_entity;
		--
		file : core.io.file_type;
	begin
		core.io.create (file, core.io.out_file, core.folder & "/map/" & file_name);
		--
		core.io.write (file, biome'pos (map.kind));
		core.io.write (file, map.width);
		core.io.write (file, map.height);
		core.io.write (file, map.chad_count);
		core.io.write (file, map.chad_limit);
		--
		for x in 0 .. map.width - 1 loop
			for y in 0 .. map.height - 1 loop
				core.io.write (file, map.tiles (x, y));
				core.io.write (file, boolean'pos (map.clips (x, y)));
				core.io.write (file, boolean'pos (map.views (x, y)));
			end loop;
		end loop;
		--
		for index in 1 .. landmark_limit     loop save_entity (file, map.landmarks (index));     end loop;
		for index in 1 .. location_limit     loop save_entity (file, map.locations (index));     end loop;
		for index in 1 .. construction_limit loop save_entity (file, map.constructions (index)); end loop;
		for index in 1 .. equipment_limit    loop save_entity (file, map.equipments (index));    end loop;
		for index in 1 .. unit_limit         loop save_entity (file, map.units (index));         end loop;
		--
		core.io.write (file, chad.enumeration'pos (map.chads (1).index));
		core.io.write (file, core.animation'pos (map.chads (1).state));
		core.io.write (file, map.chads (1).x);
		core.io.write (file, map.chads (1).y);
		--
		core.save_point (file, map.chads (1).health);
		core.save_point (file, map.chads (1).mana);
		core.save_point (file, map.chads (1).movement);
		--
		for index in attribute.enumeration loop core.save_point (file, map.chads (1).attributes (index)); end loop;
		for index in resource.enumeration  loop core.save_point (file, map.chads (1).resources  (index)); end loop;
		for index in material.enumeration  loop core.save_point (file, map.chads (1).materials  (index)); end loop;
		--
		for index in 0 .. chad.skill_limit - 1 loop core.io.write   (file, skill.enumeration'pos (map.chads (1).skills (index))); end loop;
		for index in 0 .. chad.skill_limit - 1 loop core.save_point (file, map.chads (1).points (index));                         end loop;
		--
		for kind in equipment.kind loop
			core.io.write (file, equipment.enumeration'pos (map.chads (1).equipments (kind)));
		end loop;
		--
		core.io.write (file, map.chads (1).item_count);
		--
		if map.chads (1).item_count > 0 then
			for index in 0 .. map.chads (1).item_count - 1 loop
				core.io.write (file, equipment.enumeration'pos (map.chads (1).items (index)));
			end loop;
		end if;
		--
		core.io.close (file);
		--
		core.echo (core.success, "Saved current map as '" & file_name & "'.");
		--
		core.dash;
	end save;

                                             ------------------------------------------------------------------------------------------

	procedure load (file_name : in string) is
		procedure load_entity (here : in core.io.file_type; data : out entity_description) is
		begin
			core.io.read (here, data.index);
			core.io.read (here, data.state);
			core.io.read (here, data.x);
			core.io.read (here, data.y);
		end load_entity;
		--
		file : core.io.file_type;
		this : integer;
	begin
		core.io.open (file, core.io.in_file, core.folder & "/map/" & file_name);
		--
		core.io.read (file, this); map.kind := biome'val (this);
		core.io.read (file, map.width);
		core.io.read (file, map.height);
		core.io.read (file, map.chad_count);
		core.io.read (file, map.chad_limit);
		--
		for x in 0 .. map.width - 1 loop
			for y in 0 .. map.height - 1 loop
				core.io.read (file, map.tiles (x, y));
				core.io.read (file, this); map.clips (x, y) := boolean'val (this);
				core.io.read (file, this); map.views (x, y) := boolean'val (this);
			end loop;
		end loop;
		--
		for index in 1 .. landmark_limit     loop load_entity (file, map.landmarks (index));     end loop;
		for index in 1 .. location_limit     loop load_entity (file, map.locations (index));     end loop;
		for index in 1 .. construction_limit loop load_entity (file, map.constructions (index)); end loop;
		for index in 1 .. equipment_limit    loop load_entity (file, map.equipments (index));    end loop;
		for index in 1 .. unit_limit         loop load_entity (file, map.units (index));         end loop;
		--
		core.io.read (file, this); map.chads (1).index := chad.enumeration'val (this);
		core.io.read (file, this); map.chads (1).state := core.animation'val (this);
		core.io.read (file, map.chads (1).x);
		core.io.read (file, map.chads (1).y);
		--
		core.load_point (file, map.chads (1).health);
		core.load_point (file, map.chads (1).mana);
		core.load_point (file, map.chads (1).movement);
		--
		for index in attribute.enumeration loop core.load_point (file, map.chads (1).attributes (index)); end loop;
		for index in resource.enumeration  loop core.load_point (file, map.chads (1).resources  (index)); end loop;
		for index in material.enumeration  loop core.load_point (file, map.chads (1).materials  (index)); end loop;
		--
		for index in 0 .. chad.skill_limit - 1 loop core.io.read (file, this); map.chads (1).skills (index) := skill.enumeration'val (this); end loop;
		for index in 0 .. chad.skill_limit - 1 loop core.load_point (file, map.chads (1).points (index));                                    end loop;
		--
		for kind in equipment.kind loop
			core.io.read (file, this); map.chads (1).equipments (kind) := equipment.enumeration'val (this);
		end loop;
		--
		core.io.read (file, map.chads (1).item_count);
		--
		if map.chads (1).item_count > 0 then
			for index in 0 .. map.chads (1).item_count - 1 loop
				core.io.read (file, this); map.chads (1).items (index) := equipment.enumeration'val (this);
			end loop;
		end if;
		--
		core.io.close (file);
		--
		core.echo (core.success, "Loaded map from file '" & file_name & "'.");
		--
		core.dash;
	end load;

                                             ------------------------------------------------------------------------------------------

	procedure draw is
		offset : core.vector := ((core.window_width - core.base) / 2, (core.window_height - core.base) / 2);
		view_from : core.vector := (core.camera.x - core.window_width / core.base / core.zoom / 2, core.camera.y - core.window_height / core.base / core.zoom / 2);
		view_to   : core.vector := (core.window_width / core.base / core.zoom, core.window_height / core.base / core.zoom);
		--
		time : float := 0.0;
	begin
		time := core.time;
		--
		drawn_tiles         := 0;
		drawn_views         := 0;
		drawn_landmarks     := 0;
		drawn_locations     := 0;
		drawn_constructions := 0;
		drawn_equipments    := 0;
		drawn_units         := 0;
		--
		core.clip (view_from.x, 0, map.width  - 1);
		core.clip (view_from.y, 0, map.height - 1);
		core.clip (view_to.x,   0, map.width  - 1);
		core.clip (view_to.y,   0, map.height - 1);
		--
		compute_world_visibility_grid (offset);
		compute_world_frame           (offset);
		--
		draw_tiles         (offset, view_from, view_to);
		draw_landmarks     (offset, view_from, view_to);
		draw_locations     (offset, view_from, view_to);
		draw_constructions (offset, view_from, view_to);
		draw_equipments    (offset, view_from, view_to);
		draw_units         (offset, view_from, view_to);
		--
		draw_alternative (offset, view_from, view_to);
		--
		draw_world_timer := natural (1_000_000.0 * (core.time - time));
	end draw;

                                             ------------------------------------------------------------------------------------------

	procedure draw_performance_box is
		width  : constant integer := 640;
		height : constant integer := 8 * 15 + 2 * core.icon;
		x      : constant integer := core.center_x (width);
		y      : constant integer := core.center_y (height);
	begin
		ui.draw_text_box (x, y, width, height);
		--
		ui.write ("draw_tiles_timer         :" & draw_tiles_timer'image,         x + 3 * core.icon, y + core.icon + 0 * 15, size => 15, code => true);
		ui.write ("draw_views_timer         :" & draw_views_timer'image,         x + 3 * core.icon, y + core.icon + 1 * 15, size => 15, code => true);
		ui.write ("draw_landmarks_timer     :" & draw_landmarks_timer'image,     x + 3 * core.icon, y + core.icon + 2 * 15, size => 15, code => true);
		ui.write ("draw_locations_timer     :" & draw_locations_timer'image,     x + 3 * core.icon, y + core.icon + 3 * 15, size => 15, code => true);
		ui.write ("draw_constructions_timer :" & draw_constructions_timer'image, x + 3 * core.icon, y + core.icon + 4 * 15, size => 15, code => true);
		ui.write ("draw_equipments_timer    :" & draw_equipments_timer'image,    x + 3 * core.icon, y + core.icon + 5 * 15, size => 15, code => true);
		ui.write ("draw_units_timer         :" & draw_units_timer'image,         x + 3 * core.icon, y + core.icon + 6 * 15, size => 15, code => true);
		ui.write ("draw_world_timer         :" & draw_world_timer'image,         x + 3 * core.icon, y + core.icon + 7 * 15, size => 15, code => true);
		--
		ui.write (drawn_tiles'image,         x + core.icon, y + core.icon + 0 * 15, size => 15, code => true, tint => (255, 0, 0, 255));
		ui.write (drawn_views'image,         x + core.icon, y + core.icon + 1 * 15, size => 15, code => true, tint => (255, 0, 0, 255));
		ui.write (drawn_landmarks'image,     x + core.icon, y + core.icon + 2 * 15, size => 15, code => true, tint => (255, 0, 0, 255));
		ui.write (drawn_locations'image,     x + core.icon, y + core.icon + 3 * 15, size => 15, code => true, tint => (255, 0, 0, 255));
		ui.write (drawn_constructions'image, x + core.icon, y + core.icon + 4 * 15, size => 15, code => true, tint => (255, 0, 0, 255));
		ui.write (drawn_equipments'image,    x + core.icon, y + core.icon + 5 * 15, size => 15, code => true, tint => (255, 0, 0, 255));
		ui.write (drawn_units'image,         x + core.icon, y + core.icon + 6 * 15, size => 15, code => true, tint => (255, 0, 0, 255));
	end draw_performance_box;

                                             ------------------------------------------------------------------------------------------

	procedure mapshot (file_path : in string) is
	begin
		if not map_is_revealed then
			core.echo (core.warning, "You need to reveal entire map in order to make a mapshot.");
			--
			return;
		end if;
		--
		core.create_image (map.width * core.base, map.height * core.base);
		--
		for vertical in 0 .. map.height - 1 loop
			for horizontal in 0 .. map.width - 1 loop
				core.render_image (data   => tiles (map.kind),
				                   x      => horizontal * core.base,
				                   y      => vertical   * core.base,
				                   u      => core.base * map.tiles (horizontal, vertical),
				                   v      => 0,
				                   width  => core.base,
				                   height => core.base);
			end loop;
		end loop;
		--
		for index in 1 .. landmark_limit loop
			core.render_image (data   => landmarks (landmark_index'val (map.landmarks (index).index)),
			                   x      => map.landmarks (index).x * core.base,
			                   y      => map.landmarks (index).y * core.base,
			                   u      => 0,
			                   v      => 0,
			                   width  => landmarks (landmark_index'val (map.landmarks (index).index)).width,
			                   height => landmarks (landmark_index'val (map.landmarks (index).index)).height);
		end loop;
		--
		for index in 1 .. location_limit loop
			core.render_image (data   => locations (location_index'val (map.locations (index).index)),
			                   x      => map.locations (index).x * core.base,
			                   y      => map.locations (index).y * core.base,
			                   u      => 0,
			                   v      => 0,
			                   width  => locations (location_index'val (map.locations (index).index)).width,
			                   height => locations (location_index'val (map.locations (index).index)).height);
		end loop;
		--
		for index in 1 .. construction_limit loop
			core.render_image (data   => construction.sprite (construction.enumeration'val (map.constructions (index).index)),
			                   x      => map.constructions (index).x * core.base,
			                   y      => map.constructions (index).y * core.base,
			                   u      => 0,
			                   v      => 0,
			                   width  => construction.sprite (construction.enumeration'val (map.constructions (index).index)).width,
			                   height => construction.sprite (construction.enumeration'val (map.constructions (index).index)).height);
		end loop;
		--
		for index in 1 .. equipment_limit loop
			core.render_image (data   => equipment.sprite (equipment.enumeration'val (map.equipments (index).index)),
			                   x      => map.equipments (index).x * core.base,
			                   y      => map.equipments (index).y * core.base,
			                   u      => 0,
			                   v      => 0,
			                   width  => equipment.sprite (equipment.enumeration'val (map.equipments (index).index)).width,
			                   height => equipment.sprite (equipment.enumeration'val (map.equipments (index).index)).height);
		end loop;
		--
		core.export_image (file_path);
		--
		core.echo (core.success, "Exported current world mapshot.");
		--
		core.dash;
	end mapshot;

                                             ------------------------------------------------------------------------------------------

	function map_is_revealed return boolean is
	begin
		for x in 0 .. map.width - 1 loop
			for y in 0 .. map.height - 1 loop
				if map.views (x, y) = false then
					return false;
				end if;
			end loop;
		end loop;
		--
		return true;
	end map_is_revealed;

                                             ------------------------------------------------------------------------------------------

	procedure add_chad (data : in chad.information) is
	begin
		core.echo_when (map.chad_count = map.chad_limit, core.failure, "Can't add new chad, limit reached.");
		core.increment (map.chad_count);
		--
		map.chads (map.chad_count) := data;
	end add_chad;

                                             ------------------------------------------------------------------------------------------

	procedure resource_cheat_1 is begin core.increment (map.chads (1).resources (resource.gold).value,    20); end resource_cheat_1;
	procedure resource_cheat_2 is begin core.increment (map.chads (1).resources (resource.wood).value,    10); end resource_cheat_2;
	procedure resource_cheat_3 is begin core.increment (map.chads (1).resources (resource.stone).value,   10); end resource_cheat_3;
	procedure resource_cheat_4 is begin core.increment (map.chads (1).resources (resource.metal).value,   10); end resource_cheat_4;
	procedure resource_cheat_5 is begin core.increment (map.chads (1).resources (resource.leather).value, 10); end resource_cheat_5;
	procedure resource_cheat_6 is begin core.increment (map.chads (1).resources (resource.gem).value,     10); end resource_cheat_6;

                                             ------------------------------------------------------------------------------------------

	procedure reveal_map is
	begin
		for x in 0 .. map.width - 1 loop
			for y in 0 .. map.height - 1 loop
				map.views (x, y) := true;
			end loop;
		end loop;
	end reveal_map;

                                             ------------------------------------------------------------------------------------------

	procedure restore_points is
	begin
		map.chads (1).health.value   := map.chads (1).health.limit;
		map.chads (1).mana.value     := map.chads (1).mana.limit;
		map.chads (1).movement.value := map.chads (1).movement.limit;
	end restore_points;

                                             ------------------------------------------------------------------------------------------

	procedure player_up is
	begin
		if map.chads (1).movement.value = 0 then return; end if;
		core.decrement (map.chads (1).y);
		core.clip (map.chads (1).y, 0, map.height - 1);
		map.chads (1).movement := map.chads (1).movement - 1;
		if map.clips (map.chads (1).x, map.chads (1).y) then
			core.increment (map.chads (1).y);
			if map.chads (1).movement.value > 0 then
				map.chads (1).movement := map.chads (1).movement + 1;
			end if;
		end if;
	end player_up;

                                             ------------------------------------------------------------------------------------------

	procedure player_down is
	begin
		if map.chads (1).movement.value = 0 then return; end if;
		core.increment (map.chads (1).y);
		core.clip (map.chads (1).y, 0, map.height - 1);
		map.chads (1).movement := map.chads (1).movement - 1;
		if map.clips (map.chads (1).x, map.chads (1).y) then
			core.decrement (map.chads (1).y);
			if map.chads (1).movement.value > 0 then
				map.chads (1).movement := map.chads (1).movement + 1;
			end if;
		end if;
	end player_down;

                                             ------------------------------------------------------------------------------------------

	procedure player_left is
	begin
		if map.chads (1).movement.value = 0 then return; end if;
		core.decrement (map.chads (1).x);
		core.clip (map.chads (1).x, 0, map.width  - 1);
		map.chads (1).movement := map.chads (1).movement - 1;
		if map.clips (map.chads (1).x, map.chads (1).y) then
			core.increment (map.chads (1).x);
			if map.chads (1).movement.value > 0 then
				map.chads (1).movement := map.chads (1).movement + 1;
			end if;
		end if;
	end player_left;

                                             ------------------------------------------------------------------------------------------

	procedure player_right is
	begin
		if map.chads (1).movement.value = 0 then return; end if;
		core.increment (map.chads (1).x);
		core.clip (map.chads (1).x, 0, map.width  - 1);
		map.chads (1).movement := map.chads (1).movement - 1;
		if map.clips (map.chads (1).x, map.chads (1).y) then
			core.decrement (map.chads (1).x);
			if map.chads (1).movement.value > 0 then
				map.chads (1).movement := map.chads (1).movement + 1;
			end if;
		end if;
	end player_right;

------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

	procedure generate_lake (x, y : in integer; size : in natural) is
		starts, length : integer;
	begin
		for offset_x in -size / 2 .. size / 2 loop
			starts := core.random (0, abs offset_x);
			length := core.random (size / 2, size - starts);
			--
			for repeat in 0 .. 1 loop
				for offset_y in starts .. starts + length loop
					map.tiles (x + 2 * offset_x + repeat, y + offset_y) := core.random (18, 23);
				end loop;
			end loop;
		end loop;
	end generate_lake;

                                             ------------------------------------------------------------------------------------------

	procedure draw_tiles  (offset, view_from, view_to : in core.vector) is
		time :          float       := 0.0;
		step :          core.vector := core.camera;
		size : constant integer     := core.base * core.zoom;
		hits :          natural     := 0;
	begin
		time := core.time;
		--
		for vertical in view_from.y .. view_from.y + view_to.y loop
			exit when vertical > map.height - 1;
			--
			for horizontal in view_from.x .. view_from.x + view_to.x loop
				exit when horizontal > map.width - 1;
				--
				if map.views (horizontal, vertical) then
					core.draw (data   => tiles (map.kind),
					           x      => offset.x + (horizontal - core.camera.x) * size,
					           y      => offset.y + (vertical   - core.camera.y) * size,
					           u      => core.base * map.tiles (horizontal, vertical),
					           v      => core.base * (core.animation_time mod tiles (map.kind).frames),
					           width  => core.base,
					           height => core.base,
					           ignore => true);
					--
					core.increment (drawn_tiles);
					--
					if core.cursor_inside (x      => offset.x + (horizontal - core.camera.x) * size,
					                       y      => offset.y + (vertical   - core.camera.y) * size,
					                       width  => size,
					                       height => size)
					and core.cursor_inside (x      => core.window_width  / 2 - 6 * size,
					                        y      => core.window_height / 2 - 6 * size,
					                        width  => 12 * size,
					                        height => 12 * size)
					and core.cursor_mode = core.cursor_left
					and not ui.prioritize then
						target.x         := horizontal;
						target.y         := vertical;
						core.cursor_mode := core.cursor_none;
					end if;
					--
					if core.cursor_inside (x      => offset.x + (target.x - core.camera.x) * size,
					                       y      => offset.y + (target.y - core.camera.y) * size,
					                       width  => size,
					                       height => size)
					and core.cursor_mode = core.cursor_left
					and not ui.prioritize then
						world.map.chads (1).x := horizontal + 1;
						world.map.chads (1).y := vertical;
					end if;
				end if;
			end loop;
		end loop;
		--
		if target.x /= -1 and target.y /= -1 then
			step := core.camera;
			hits := 0;
			--
			core.draw (data   => arrow_target,
			           x      => offset.x + (target.x - core.camera.x) * size,
			           y      => offset.y + (target.y - core.camera.y) * size,
			           factor => core.zoom);
			--
			loop
				exit when (step.x = target.x - 1 and step.y = target.y - 1) or (hits = 6);
				--
				if step.x < target.x and step.y < target.y then
					core.draw (arrow_lower_right, offset.x + (step.x + 1 - core.camera.x) * size, offset.y + (step.y + 1 - core.camera.y) * size, factor => core.zoom);
					step.x := step.x + 1;
					step.y := step.y + 1;
				elsif step.x > target.x and step.y < target.y then
					core.draw (arrow_lower_left, offset.x + (step.x - 1 - core.camera.x) * size, offset.y + (step.y + 1 - core.camera.y) * size, factor => core.zoom);
					step.x := step.x - 1;
					step.y := step.y + 1;
				elsif step.x = target.x and step.y < target.y then
					core.draw (arrow_lower, offset.x + (step.x - core.camera.x) * size, offset.y + (step.y + 1 - core.camera.y) * size, factor => core.zoom);
					step.y := step.y + 1;
				elsif step.x < target.x and step.y = target.y then
					core.draw (arrow_right, offset.x + (step.x + 1 - core.camera.x) * size, offset.y + (step.y - core.camera.y) * size, factor => core.zoom);
					step.x := step.x + 1;
				elsif step.x > target.x and step.y = target.y then
					core.draw (arrow_left, offset.x + (step.x - 1 - core.camera.x) * size, offset.y + (step.y - core.camera.y) * size, factor => core.zoom);
					step.x := step.x - 1;
				elsif step.x < target.x and step.y > target.y then
					core.draw (arrow_upper_right, offset.x + (step.x + 1 - core.camera.x) * size, offset.y + (step.y - 1 - core.camera.y) * size, factor => core.zoom);
					step.x := step.x + 1;
					step.y := step.y - 1;
				elsif step.x > target.x and step.y > target.y then
					core.draw (arrow_upper_left, offset.x + (step.x - 1 - core.camera.x) * size, offset.y + (step.y - 1 - core.camera.y) * size, factor => core.zoom);
					step.x := step.x - 1;
					step.y := step.y - 1;
				elsif step.x = target.x and step.y > target.y then
					core.draw (arrow_upper, offset.x + (step.x - core.camera.x) * size, offset.y + (step.y - 1 - core.camera.y) * size, factor => core.zoom);
					step.y := step.y - 1;
				end if;
				--
				hits := hits + 1;
			end loop;
		end if;
		--
		draw_tiles_timer := natural (1_000_000.0 * (core.time - time));
	end draw_tiles;

                                             ------------------------------------------------------------------------------------------

	procedure compute_world_visibility_grid (offset : in core.vector) is
	begin
		for vertical in 0 .. map.height - 1 loop
			exit when offset.y + (vertical - core.camera.y) * core.base * core.zoom > core.window_height;
			--
			for horizontal in 0 .. map.width - 1 loop
				exit when offset.x + (horizontal - core.camera.x) * core.base * core.zoom > core.window_width;
				--
				if not ((horizontal - core.camera.x) ** 2 + (vertical - core.camera.y) ** 2 > view_reach * 2) then
					map.views (horizontal, vertical) := true;
				end if;
			end loop;
		end loop;
	end compute_world_visibility_grid;

                                             ------------------------------------------------------------------------------------------

	procedure compute_world_frame (offset : in core.vector) is
		x      : constant integer := core.base * core.zoom * (-1 - core.camera.x) + offset.x;
		y      : constant integer := core.base * core.zoom * (-1 - core.camera.y) + offset.y;
		width  : constant integer := core.base * core.zoom * (map.width  + 2);
		height : constant integer := core.base * core.zoom * (map.height + 2);
	begin
		core.draw_horizontally (border_upper, x + core.base * core.zoom,         y,                                  width  - 2 * core.base * core.zoom, core.zoom);
		core.draw_horizontally (border_lower, x + core.base * core.zoom,         y - core.base * core.zoom + height, width  - 2 * core.base * core.zoom, core.zoom);
		core.draw_vertically   (border_left,  x,                                 y + core.base * core.zoom,          height - 2 * core.base * core.zoom, core.zoom);
		core.draw_vertically   (border_right, x - core.base * core.zoom + width, y + core.base * core.zoom,          height - 2 * core.base * core.zoom, core.zoom);
		--
		core.draw (corner_upper_left,  x,                                 y,                                  factor => core.zoom);
		core.draw (corner_upper_right, x - core.base * core.zoom + width, y,                                  factor => core.zoom);
		core.draw (corner_lower_left,  x,                                 y - core.base * core.zoom + height, factor => core.zoom);
		core.draw (corner_lower_right, x - core.base * core.zoom + width, y - core.base * core.zoom + height, factor => core.zoom);
	end compute_world_frame;

                                             ------------------------------------------------------------------------------------------

	procedure draw_landmarks (offset, view_from, view_to : in core.vector) is
		time : float := 0.0;
	begin
		time := core.time;
		--
		for index in 1 .. landmark_limit loop
			if  map.views (map.landmarks (index).x, map.landmarks (index).y)
			and map.landmarks (index).x > view_from.x and map.landmarks (index).x < view_from.x + view_to.x
			and map.landmarks (index).y > view_from.y and map.landmarks (index).y < view_from.y + view_to.y then
				core.draw (data => landmarks (landmark_index'val (map.landmarks (index).index)),
				           x    => offset.x + (map.landmarks (index).x - core.camera.x) * core.base * core.zoom,
				           y    => offset.y + (map.landmarks (index).y - core.camera.y) * core.base * core.zoom);
				--
				core.increment (drawn_landmarks);
				--
				if core.cursor_inside (x      => offset.x + (map.landmarks (index).x - core.camera.x) * core.base * core.zoom,
				                       y      => offset.y + (map.landmarks (index).y - core.camera.y) * core.base * core.zoom,
				                       width  => landmarks (landmark_index'val (map.landmarks (index).index)).width,
				                       height => landmarks (landmark_index'val (map.landmarks (index).index)).height)
				and core.cursor_mode = core.cursor_middle
				and not ui.prioritize then
					core.write_text_box (landmark_description (landmark_index'val (map.landmarks (index).index)).name.all);
				end if;
			end if;
		end loop;
		--
		draw_landmarks_timer := natural (1_000_000.0 * (core.time - time));
	end draw_landmarks;

                                             ------------------------------------------------------------------------------------------

	procedure draw_locations (offset, view_from, view_to : in core.vector) is
		time    : float := 0.0;
		sprite  : core.sprite;
	begin
		time := core.time;
		--
		for index in 1 .. location_limit loop
			if  map.views (map.locations (index).x, map.locations (index).y)
			and map.locations (index).x > view_from.x and map.locations (index).x < view_from.x + view_to.x
			and map.locations (index).y > view_from.y and map.locations (index).y < view_from.y + view_to.y then
				core.draw (data   => locations (location_index'val (map.locations (index).index)),
				           x      => offset.x + (map.locations (index).x - core.camera.x) * core.base * core.zoom,
				           y      => offset.y + (map.locations (index).y - core.camera.y) * core.base * core.zoom,
				           state  => core.animation'val (map.locations (index).state));
				--
				core.increment (drawn_locations);
				--
				if  core.cursor_inside (x      => offset.x + (map.locations (index).x - core.camera.x) * core.base * core.zoom,
				                        y      => offset.y + (map.locations (index).y - core.camera.y) * core.base * core.zoom,
				                        width  => locations (location_index'val (map.locations (index).index)).width,
				                        height => locations (location_index'val (map.locations (index).index)).height)
				and core.cursor_mode = core.cursor_middle
				and not ui.prioritize then
					core.write_text_box (location_description (location_index'val (map.locations (index).index)).name.all);
				end if;
			end if;
			--
			if map.locations (index).state = 1 and core.animation_time = 0 then
				map.locations (index).state := 2;
			end if;
			--
			if  core.camera.x > map.locations (index).x - 2
			and core.camera.x < map.locations (index).x + 1 + locations (location_index'val (map.locations (index).index)).width  / core.base
			and core.camera.y > map.locations (index).y - 2
			and core.camera.y < map.locations (index).y + 1 + locations (location_index'val (map.locations (index).index)).height / core.base
			and map.locations (index).state = 0
			and core.signal_code'pos (core.signal_mode) = core.signal_code'pos (core.signal_e)
			and not ui.prioritize then
				declare player : chad.information renames world.map.chads (1);
				        --
				        data : effect.information := location_description (location_index'val (map.locations (index).index)).evoke;
				        --
				        attribute_index : attribute.enumeration;
				        skill_index     : skill.enumeration;
				        resource_index  : resource.enumeration;
				        material_index  : material.enumeration;
				begin
					case data.kind is
						when effect.idle => null;
						--
						when effect.modify_attribute => attribute_index := attribute.enumeration'val (data.modifier);
						                         player.attributes (attribute_index) := player.attributes (attribute_index) + data.amount;
						                         ui.echo ("Player " & (if data.amount < 0 then "lost" else "gained") & integer'image (abs data.amount) & " "
						                         & attribute.description (attribute_index).name.all & " attribute points.");
						--
						when effect.modify_skill => null;
						--~when effect.modify_skill => skill_index := skill.enumeration'val (data.modifier);
						                     --~player.skills (skill_index) := player.skills (skill_index) + data.amount;
						                     --~ui.echo ("Player " & (if data.amount < 0 then "lost" else "gained") & integer'image (abs data.amount) & " "
						                     --~& skill.description (skill_index).name.all & " skill points.");
						--
						when effect.modify_resource => resource_index := resource.enumeration'val (data.modifier);
						                         player.resources (resource_index) := player.resources (resource_index) + data.amount;
						                         ui.echo ("Player " & (if data.amount < 0 then "lost" else "gained") & integer'image (abs data.amount) & " "
						                         & resource.description (resource_index).name.all & " resource points.");
						--
						when effect.modify_material => material_index := material.enumeration'val (data.modifier);
						                        player.materials (material_index) := player.materials (material_index) + data.amount;
						                        ui.echo ("+" & data.amount'image & " " & material.description (material_index).name.all);
					end case;
				end;
				--
				map.locations (index).state := 1;
			end if;
		end loop;
		--
		draw_locations_timer := natural (1_000_000.0 * (core.time - time));
	end draw_locations;

                                             ------------------------------------------------------------------------------------------

	procedure draw_constructions (offset, view_from, view_to : in core.vector) is
		time : float   := 0.0;
		x    : integer := 0;
		y    : integer := 0;
		--
		this : construction.enumeration;
	begin
		time := core.time;
		--
		for index in 1 .. construction_limit loop
			if  map.views (map.constructions (index).x, map.constructions (index).y)
			and map.constructions (index).x > view_from.x and map.constructions (index).x < view_from.x + view_to.x
			and map.constructions (index).y > view_from.y and map.constructions (index).y < view_from.y + view_to.y then
				x    := offset.x + (map.constructions (index).x - core.camera.x) * core.base * core.zoom;
				y    := offset.y + (map.constructions (index).y - core.camera.y) * core.base * core.zoom;
				this := construction.enumeration'val (map.constructions (index).index);
				--
				core.draw (construction.sprite (this), x, y);
				--
				if  core.cursor_inside (x, y, construction.sprite (this).width, construction.sprite (this).height)
				and core.cursor_mode = core.cursor_middle
				and not ui.prioritize then
					core.write_text_box (construction.description (this).name.all);
				end if;
				--
				core.increment (drawn_constructions);
			end if;
		end loop;
		--
		draw_constructions_timer := natural (1_000_000.0 * (core.time - time));
	end draw_constructions;

                                             ------------------------------------------------------------------------------------------

	procedure draw_equipments (offset, view_from, view_to : in core.vector) is
		time : float := 0.0;
		x    : integer := 0;
		y    : integer := 0;
		--
		this : equipment.enumeration;
	begin
		time := core.time;
		--
		for index in 1 .. equipment_limit loop
			if map.views (map.equipments (index).x, map.equipments (index).y)
			and map.equipments (index).x > view_from.x and map.equipments (index).x < view_from.x + view_to.x
			and map.equipments (index).y > view_from.y and map.equipments (index).y < view_from.y + view_to.y then
				x    := offset.x + (map.equipments (index).x - core.camera.x) * core.base * core.zoom;
				y    := offset.y + (map.equipments (index).y - core.camera.y) * core.base * core.zoom;
				this := equipment.enumeration'val (map.equipments (index).index);
				--
				core.draw (equipment.sprite (this), x, y, state => core.idle);
				--
				if  core.cursor_inside (x, y, equipment.sprite (this).width, equipment.sprite (this).height)
				and core.cursor_mode = core.cursor_middle
				and equipment.enumeration'pos (this) /= equipment.enumeration'pos (equipment.none)
				and not ui.prioritize then
					core.write_text_box (equipment.description (this).name.all);
				end if;
				--
				core.increment (drawn_equipments);
			end if;
			--
			if  map.equipments (index).x = core.camera.x
			and map.equipments (index).y = core.camera.y
			and core.signal_code'pos (core.signal_mode) = core.signal_code'pos (core.signal_e) then
				if map.chads (1).item_count < chad.item_limit and map.equipments (index).index /= equipment.enumeration'pos (equipment.none) then
					map.chads (1).items (map.chads (1).item_count) := equipment.enumeration'val (map.equipments (index).index);
					--
					core.increment (map.chads (1).item_count);
					--
					map.equipments (index).index := equipment.enumeration'pos (equipment.none);
				end if;
			end if;
		end loop;
		--
		draw_equipments_timer := natural (1_000_000.0 * (core.time - time));
	end draw_equipments;

                                             ------------------------------------------------------------------------------------------

	procedure draw_units (offset, view_from, view_to : in core.vector) is
		time : float := 0.0;
	begin
		time := core.time;
		--
		for index in 1 .. unit_limit loop
			if  map.views (map.units (index).x, map.units (index).y)
			and map.units (index).x > view_from.x and map.units (index).x < view_from.x + view_to.x
			and map.units (index).y > view_from.y and map.units (index).y < view_from.y + view_to.y then
				core.draw (data  => unit.base (unit.description (unit.enumeration'val (map.units (index).index)).kind),
				           x     => offset.x + (map.units (index).x - core.camera.x) * core.base * core.zoom,
				           y     => offset.y + (map.units (index).y - core.camera.y) * core.base * core.zoom,
				           state => core.animation'val (map.units (index).state));
				--
				for kind in equipment.kind loop
					if equipment.enumeration'pos (unit.description (unit.enumeration'val (map.units (index).index)).equipments (kind))
					/= equipment.enumeration'pos (equipment.none) then
						core.draw (data  => equipment.sprite (unit.description (unit.enumeration'val (map.units (index).index)).equipments (kind)),
						           x     => offset.x + (map.units (index).x - core.camera.x) * core.base * core.zoom,
						           y     => offset.y + (map.units (index).y - core.camera.y) * core.base * core.zoom,
						           state => core.animation'val (map.units (index).state));
					end if;
				end loop;
				--
				core.increment (drawn_units);
			end if;
		end loop;
		--
		for index in 1 .. map.chad_count loop
			if map.views (map.chads (index).x, map.chads (index).y) then
				core.draw (data  => chad.sprite (map.chads (index).index),
				           x     => offset.x + (map.chads (index).x - core.camera.x) * core.base * core.zoom,
				           y     => offset.y + (map.chads (index).y - core.camera.y) * core.base * core.zoom,
				           state => map.chads (index).state);
				--
				for kind in equipment.kind loop
					core.draw (data  => equipment.sprite (map.chads (index).equipments (kind)),
					           x     => offset.x + (map.chads (index).x - core.camera.x) * core.base * core.zoom,
					           y     => offset.y + (map.chads (index).y - core.camera.y) * core.base * core.zoom,
					           state => map.chads (index).state);
				end loop;
				--
				core.increment (drawn_units);
			end if;
		end loop;
		--
		draw_units_timer := natural (1_000_000.0 * (core.time - time));
	end draw_units;

                                             ------------------------------------------------------------------------------------------

	procedure draw_alternative (offset, view_from, view_to : in core.vector) is
		time : float := 0.0;
	begin
		time := core.time;
		--
		for vertical in view_from.y .. view_from.y + view_to.y loop
			exit when vertical > map.height - 1;
			--
			for horizontal in view_from.x .. view_from.x + view_to.x loop
				exit when horizontal > map.width - 1;
				--
				if (horizontal - core.camera.x) ** 2 + (vertical - core.camera.y) ** 2 > view_reach then
					core.draw (data   => dark,
					           x      => offset.x + (horizontal - core.camera.x) * core.base * core.zoom,
					           y      => offset.y + (vertical   - core.camera.y) * core.base * core.zoom);
					--
					core.increment (drawn_views);
				end if;
			end loop;
		end loop;
		--
		draw_views_timer := natural (1_000_000.0 * (core.time - time));
	end draw_alternative;

                                             ------------------------------------------------------------------------------------------

	procedure compute_earth_to_water_transition is
		matrix : array (0 .. 1, 0 .. 1) of natural;
	begin
		for x in 1 .. map.width - 2 loop
			for y in 1 .. map.height - 2 loop
				matrix (0, 0) := boolean'pos (map.tiles (x - 1, y - 1) not in 18 .. 23);
				matrix (1, 0) := boolean'pos (map.tiles (x,     y - 1) not in 18 .. 23);
				matrix (0, 1) := boolean'pos (map.tiles (x - 1, y    ) not in 18 .. 23);
				matrix (1, 1) := boolean'pos (map.tiles (x,     y    ) not in 18 .. 23);
				--
				if map.tiles (x, y) not in 18 .. 23 and map.tiles (x,     y + 1)     in 18 .. 23 then map.tiles (x,     y    ) := 24; end if;
				if map.tiles (x, y)     in 18 .. 23 and map.tiles (x,     y + 1) not in 18 .. 23 then map.tiles (x,     y + 1) := 25; end if;
				if map.tiles (x, y) not in 18 .. 23 and map.tiles (x + 1, y    )     in 18 .. 23 then map.tiles (x,     y    ) := 26; end if;
				if map.tiles (x, y)     in 18 .. 23 and map.tiles (x + 1, y    ) not in 18 .. 23 then map.tiles (x + 1, y    ) := 27; end if;
				--
				if    matrix = ((1, 1), (1, 0)) then map.tiles (x - 1, y - 1) := 28;
				elsif matrix = ((1, 0), (1, 1)) then map.tiles (x,     y - 1) := 29;
				elsif matrix = ((1, 1), (0, 1)) then map.tiles (x - 1, y    ) := 30;
				elsif matrix = ((0, 1), (1, 1)) then map.tiles (x,     y    ) := 31;
				elsif matrix = ((0, 0), (0, 1)) then map.tiles (x,     y    ) := 32;
				elsif matrix = ((0, 1), (0, 0)) then map.tiles (x - 1, y    ) := 33;
				elsif matrix = ((0, 0), (1, 0)) then map.tiles (x,     y - 1) := 34;
				elsif matrix = ((1, 0), (0, 0)) then map.tiles (x - 1, y - 1) := 35;
				end if;
			end loop;
		end loop;
	end compute_earth_to_water_transition;

------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

end world;