View source for Hex map

{{short description|Map subdivided into a hexagonal tiling, small regular hexagons of identical size}}
[[Image:Wesnoth-1.4-1.jpg|thumb|300px|''[[The Battle for Wesnoth]]'', a computer game based on the hex grid]]
A '''hex map''', '''hex board''', or '''hex grid''' is a [[game board]] design commonly used in [[simulation games]] of all scales, including [[wargame]]s, [[role-playing game]]s, and [[strategy game]]s in both [[board game]]s and [[video game]]s. A hex map is subdivided into a [[hexagonal tiling]], small [[regular polygon|regular]] [[hexagon]]s of identical size.

==Advantages and disadvantages==
The primary advantage of a hex map over a traditional [[square grid]] map is that the distance between the center of each and every pair of adjacent hex cells (or ''hexes'') is the same. By comparison, in a square grid map, the distance from the center of each square cell to the center of the four diagonal adjacent cells it shares a corner with is [[square root of 2|{{sqrt|2}}]] times that of the distance to the center of the four adjacent cells it shares an edge with. This equidistant property of all adjacent hexes is desirable for games in which the measurement of movement is a factor. The other advantage is the fact that neighbouring cells always share edges; there are no two cells with contact at only a point.

One disadvantage of a hex map is that hexes have adjacent cells in only six directions instead of eight, as in a square grid map. Commonly, cells will form continuous straight lines "up" and "down", or "north" and "south", in which case the other four adjacent cells lie "north-west", "north-east", "south-west" and "south-east". As a result, no hex cell has an adjacent hex cell lying directly east or west of it, making "horizontal" movement in a straight line impossible. Instead, paths in these directions, and any other path that does not bisect one of the six cell edges, will "zig-zag"; since no two directions are [[orthogonal]], it is impossible to move forward in one direction without moving backwards slightly in the other.

{{Multiple image
| image1 = HexMapDistance.svg
| image2 = Hex Grid Movement.png
| align = right
| image3 = Square Grid Movement.png
| total_width = 800
| caption1 = Advantage of hex maps in games: consistent distance from center to center compared to squares.<br />This distance is [[square root of 3|{{sqrt|3}}]] times that of a hexagon side.
| caption2 = Horizontal movement on a hex map. Vertical movement is required.
| caption3 = Horizontal movement on a square map. Vertical movement is not required.
}}{{multiple image
| width     = 150
| image1    = Glinski chess bishop.png
| caption1  = A [[hexagonal chess]] board, showing the three-colour system and the diagonal moves of a [[bishop (chess)|bishop]].
| image2    = Fallout camera angles.png
| caption2  = [[POV-Ray]] render mimicking ''[[Fallout (video game)|Fallout]]''{{'}}s [[trimetric projection]] and hexagonal grid.
}}

Games that traditionally use the four [[cardinal direction]]s, or otherwise suit a square grid, may adapt to a hex grid in different ways. For example, [[hexagonal chess]] replaces the four directions of orthogonal movement (along ranks and files) with the six directions to adjacent cells, through cell edges. The four directions of diagonal movement are likewise replaced with the six directions that lie through [[vertex (geometry)|vertices]] of the cell; these "diagonal" movements travel along the edge between a pair of adjacent cells before arriving at another cell. A three-colour grid aids in visualising this movement, since it preserves the traditional chessboard's property that pieces moving diagonally land only on cells of the same colour.

==Uses==
[[File:Catan Universe fixed setup.svg|thumb|A ''[[Catan]]'' board]]
The hex map has been a favourite for game designers since 1961, when [[Charles S. Roberts]] of the [[Avalon Hill]] game company published the second edition of ''[[Gettysburg (game)|Gettysburg]]'' with a hex map. The hex grid is a distinguishing feature of the games from many wargame publishers, and a few other games (such as ''[[The Settlers of Catan]])''.

The hex map has also been popular for role-playing game wilderness maps. They were used in the ''Dungeons & Dragons'' boxed sets of the 1980s and related [[TSR, Inc.|TSR]] products. [[Game Designers' Workshop|GDW]] also used a hex grid map in mapping space for their science-fiction [[Role-playing game|RPG]] ''[[Traveller (role-playing game)|Traveller]]''.

A number of [[abstract game]]s are played on a hex grid, such as
* ''[[Abalone (board game)|Abalone]]''
* the six games of the ''[[GIPF project|GIPF]]'' series
* ''[[Hex (board game)|Hex]]''
* ''[[Havannah (board game)|Havannah]]''
* ''[[Y_(game)|Y]]''
* ''[[Chinese Checkers]]''
* ''[[Agon (game)|Agon]]''

Several [[Chess variant|variants of chess]] have also been invented for a hex board. 

The television game show ''[[Blockbusters (US game show)|Blockbusters]]'' (1980–1982, 1987) was also based on a hex grid. 

Early examples of [[strategy video game]]s that use hex maps include 1983's ''[[Nobunaga's Ambition]]'',<ref>{{citation|first=Evan|last=Brooks|magazine=[[Computer Gaming World]]|date=September 1988|issue=51|pages=12, 34, 48–9|title=Romance of the Three Kingdoms|quote=When war begins, the screen changes to a 5x10 hex area for the execution of the battle. Terrain is effectively delineated as hill, mountain, village, river, plain or castle; deployment is dependent on the route of invasion.}}</ref> 1989's ''[[Military Madness]]'' (the first entry in the [[Nectaris series|''Nectaris'' series]]),<ref>{{cite web|title=Military Madness: Nectaris Explodes into Action on Xbox LIVE Arcade|date=September 30, 2009|publisher=GameZone|url=https://www.gamezone.com/news/item/military_madness_nectaris_explodes_into_action_on_xbox_live_arcade|access-date=2011-05-19}}</ref> and 1991's ''[[Master of Monsters]]''.<ref>{{cite web|title=Top 10 Renovation Games|url=http://uk.retro.ign.com/articles/882/882363p1.html|publisher=[[IGN]]|access-date=1 January 2012|date=June 17, 2008}}</ref> The first ''[[Civilization (series)|Civilization]]'' had a hex map version during development, but designers decided against it because "the world was not ready ... it was too freaky".<ref name=part2>{{cite interview|last=Meier|first=Sid|interviewer=[[Soren Johnson]]|title=Designer Notes 24: Sid Meier - Part 2 |type=audio |url=https://www.idlethumbs.net/designernotes/episodes/sid-meier-part-2/ |date=2016-11-23|access-date=2017-07-31|language=en}}</ref> While the first four iterations of the popular [[Civilization (series)|''Civilization'' computer game franchise]] used square maps, ''[[Civilization V]],'' ''[[Civilization VI]], and [[Civilization VII]]'' use hexagonal maps. Other games that use hex maps are ''[[The Battle for Wesnoth]]'', ''[[Dragon Age Journeys]]'', ''[[Heroes of Might and Magic III]]'', ''[[Forge of Empires]]'' and ''[[UniWar]]''.

==See also==
* [[Ataxx#Ataxx clones|Hexxagon]], a [[board game]]
* [[Hexagonal tiling]]

==References==
{{reflist|30em}}

==External links==
{{Commons category|Hex maps|Hex maps}}
* [https://www.nomic.net/~uckelman/mkhexgrid mkhexgrid, a hex grid and hex paper utility]
* [https://incompetech.com/graphpaper/hexagonal/ Free online hexagonal graph paper PDF generator]
* [https://www.hexographer.com/ Hexographer, a program for making role-playing game wilderness hex maps in a "classic" style]
* [https://hextml.playest.net/ Hextml, an online program to make hex maps]
* [https://rhysmakesthings.com/gm_friend GM Friend hex mapping tool, an online program to make hex maps with a random map generator]
* [https://www.redblobgames.com/grids/hexagons/ RedBlobGames, Hexagonal Grids, a reference for hexagonal grid algorithms]
* [http://supfam.org/SUPERFAMILY/dcGO/supraHex.html supraHex] A supra-hexagonal map for analysing high-dimensional omics data.
* [https://archive.today/20141214082648/http://keekerdc.com/2011/03/hexagon-grids-coordinate-systems-and-distance-calculations/ mathematical discussion of implementing the x,y,z axis in hexagonal applications]
* [https://www.unrealengine.com/marketplace/hex-map-grid Unreal Engine 4 HexMap grid extension]

[[Category:Board game terminology]]
[[Category:Map types]]
[[Category:Hexagonal tilings]]
[[Category:Game terminology]]