Deep Battle Design Notes 1 – Musing on Hex/Square Grids

What is this relatively recent thing with Steven and hexes? My mate Chris is the hex-meister of the universe but normally I prefer free form tables without a grid. So how come I’ve gone all-hexy e.g. my recent maps for the Battle of Kharkov (10km Hexes; 20km hexes) and operational terrain experiments (River Templates, MDF River, Experimenting, Felt Rivers, Felt Railways)?

A grid offers a handful of advantages which I think are particularly apt for Operational level wargaming. I’m not the only one who thinks so. When I did my Review of Wargaming Rules I could use for the Operational Level of War, I saw a trend towards hex or square grids. So, when I write my own Deep Battle rule set, I’m going to use a hex/square grid of some kind.

Why use a grid for operational games

I’m keen to uses a hex/square grid for my new set of Operational rules for a few reasons. As I see it, grids offer these advantages at this game resolution:

  • regularise movement
  • gloss over the terrain details which is particularly appropriate for the higher level of abstraction of operational rules
  • make it obvious when enemy forces are in contact – they are either in the same hex/square or in adjacent ones
  • make it obvious when a force has massed to attack – the units are in the same hex/square
  • allow a defending force to spread out and still have a continuous frontage – whether a unit is small or large they still occupy a hex/square

Can anybody other other reasons for (or against) using a grid at operational level of wargaming?

Kharkov 1942 Map for Deep Battle with 20km Hexes

Kharkov 1942 Map for Deep Battle with 20km Hexes

The Problems with Grids

Both Hexes and Squares come with geometric difficulties. Two in particular:

  • Angles of joins have to match the grid
  • Movement is easier along a grain

These are not fatal problems, but you do have to consider them if you want to use a grid based game system.

Angles of joins have to match the grid

In hex grids all angles are variations on 60 degrees. So roads and railway lines cross at 60 degrees; they cannot cross at 90 degrees. Any curves in rivers are also on variations of 60 degrees, although I don’t mind this so much as you can make rivers look nice and curvy – see my MDF River Sections for 4 Inch Hexes.

Square grids offer more angles, two, but that is still pretty limited. Angles to a square adjacent to a flat edge are 90 degrees. There is also the option of 45 degrees to squares connected diagonally. So roads and railways could join at 90 degrees or 45 degrees. But you cannot, for example, model a 60 degree join. Rivers, if you want them along a edge, would be restricted to 90 degree joins making rivers very, well non-curvy.

Movement is easier along a grain

The second problem with grids is the grain. Depending on the route units travel on the grid they are either moving with the grain or against the grain. The following diagram illustrates the problem – in this case using a hex grid. Blue Route A is against the grain and is a kind of zigzag. Red Route B is with the grain and it just takes one change of direction to reach the destination. The catch is that, in hexes, both Route A and Route B are the same length. Yet geometrically Route A should be the direct, shortest, route and Route B should be a longer detour.

Problem with Hexes - Distances against the grain

Problem with Hexes – Distances against the grain

Square grids also have a geometric problem. The diagonals. In the following diagram it is pretty obvious that the distance of Green Route C is one square and the distance of Red Route D is two squares. But what about Blue Route E? What is the distance of a diagonal movement. Geometrically it is 1.5 squares and some rules factor that in. Other game systems forbid a diagonal movement so, effectively insist on travel paths like Red Route D. Yet others allow the diagonal movement but give it a movement cost of two squares. I’ve put this observation under the “grain” problem because effectively square grids have two grains – via the edge and diagonal – and the grains are inconsistent with each other.

Problem with Squares - Distances on the diagonal

Problem with Squares – Distances on the diagonal

Although grain is a problem for a grid, you can use it to your advantage. For example, you can draw maps so that movement in certain directions is encouraged (along the grain) and other movement discouraged (against the grain). For example, in Battle of Moscow map I’m drawing at the moment, I’ve made the German direct route to Moscow against the grain to make it harder and the indirect flanking movement from the south with the grain, making it easier. This simple choice should encourage the Germans to seek a flanking manoeuvre.

Other people’s games with hex/square grids

I didn’t record the table type in my original review of Operational Level Wargames, so here is the list:

Wargaming Rules Table
Assault Gun Hex grid
Bloody Big World War Two Battles Normal
Division Commander Normal
DivTac Normal
Drive on Moscow Area
Engle Matrix Games Area
Field of Battle WW2 Normal
Hell’s Gate Hex grid
Hexblitz Hex grid
High Command Normal / Square grid
Hurrah Stalino Square grid
Kiss Rommel Normal / Square grid
Kriegsspiel Normal
Lightning War Normal
Megablitz Normal
Not Quite Mechanised (NQM) Normal
Operational Art Hex grid
Panzer Korps Normal
PanzerGruppe Hex grid
Pz8 Normal
Rapier Offensive Square grid
Rommel Square grid

5 comments to Deep Battle Design Notes 1 – Musing on Hex/Square Grids

  • George Wyllie

    Interesting. I recently started using a hex table, although I only pay heed to the hexes for movement and firing ranges, i. e. 2hex, 3hex, etc. the actual route through a hex is ignored. Unorthodox no doubt but it suits me. BTW congrats on a great blog

  • Brooks Flugaur-Leavitt

    If your rules use grid spaces as definite units of measurement, I’m a strong supporter of the hexagon. The effect of roads and rough going on movement rates will obscure the issues you describe with the grain unless you have large areas with no change in movement rate.

  • Hexes aren’t as limited on road angles as you suggest. In addition to 60 degree, you can easily have 30 degrees. With off-centre roads, you can also have 90 degree angles and hence crossroads. In fact, you have a handy article about it on your site. : )

  • Another advantage of hex/square grids is that you can have grid references, which makes unambiguous recording of positions of deployment (especially hidden) and reinforcements a lot easier.

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