In this blogpost, I would like to discuss the triangular grid. I think it's a grid that has not been fully explored in wargaming (hexagonal grids and square grids getting much more attention), but it is wortwhile to look at some of its advantages and disadvantages.
Relation between the triangular and hexagonal grid
There is a strong relation between the classic hexagonal tiling, and a triangular tiling.
Mathematically, they are each other's dual tiling. This means that if you take the centre points of each hexagon, and you connect these centre points together, you get the triangular tiling. This also works in the other direction: if you take the centre points of each triangle, and connecting them together, you get the hexagonal tiling.
This duality results in a nice property: when playing a game on a triangular grid, placing the pieces on the corner points and moving them along edges, is equivalent to playing that game on a hexagonal grid by placing the pieces inside the hexagons and moving them across edges. And vice versa, playing a game on the corners and along edges of a hexagonal grid, is equivalent to putting the pieces in the triangles and moving them across edge boundaries.
There is however a major issue with the triangular grid, which is the asymmetry of connections between the triangles. Unlike a hexagon grid, triangle can connect edge-to-edge, but also point-to-point in various configurations. This lack of symmetry is the most likely reason why triangular tiles have not been really considered for wargaming.
Has the triangular grid been used before?
When trying to look up whether (board) wargames make use of a triangular grid, surprisingly few results turn up. Most of the games that use a triangular grid, use the dual property, effectively using a hexagonal grid. The triangular grid is then merely an esthetic element in the design of the game. See e.g. games that employ the "Triangle System", See also this page at Forsage Games.
Most games that use the triangles themselves as areas usually are abstract boardgames. Some examples are: Blokus Trigon or Go played on a triangular grid.
Let us assume we do want to design a miniature wargame using a triangular grid. One of the things we need is a counting procedure for counting distances from one grid cell to another cell, and preferably, we would like that counting procedure to approximate the Euclidean distance between the centre points of both grid cells.
Using some simple goniometry, and setting the distance between the (barycentric) centre points between 2 adjoining triangles to 1, we arrive at the following relations:
Taking the red dot as starting point, we see that we can get to edge-to-edge triangles (yellow dots) using distance 1. The triangle directly opposite (blue dot) requries distance 2. Both triangles that touch the starting triangle, but are not directly opposite, are at distance square root of 3, or 1.73.
Rounding up 1.73 to 2, we get the following, rather simple, counting procedure for measuring distances:
- When moving from edge-to-edge, count 1;
- When moving from point-to-point (any configuration), count 2.
|(Image from "20 Fun Grid Facts (Hexgrids)")|
(You might wonder how this is possible, given that we have rounded one distance 1.73 to 2 ... but there are also 2 modes of moving on a hexagonal grid: straight ahead from hexagon to hexagon, or in a "zig-zag" pattern, which correspond to different connecting triangles ... these are not exactly equal, although we often consider them as such on the hexagonal grid.)
Ok, let's put it all together. How far can we move on a triangular grid given various amounts of movement points? The diagram below illustrate the movement ranges, using 1 movement point to move across an edge, 2 movement points to move across a corner.
Facing, Battlelines and firing arcs
When located in a triangle, a unit can face in 12 different directions: 3 sides, 3 corners, but there also 6 other directions that line up with rows of triangles (see diagram below). On a square grid, there are 8 natural facings, a hexagonal grid has 6 edges + 6 corners, also resulting in 12.
The orientation and facings, having 12 "natural" directions on the grid, might be the biggest advantage of the triangular grid. However, just an in squares, the connections between the grid cells is asymmetric. But this is also the case when considering the "zig-zag" directions in a hexagonal grid.
Firing arcs become a little more complex. The diagram below shows firing arcs at 60 degrees, and a distance of 4. Note the little discrepancy in the firing arc for the unit on the right.
All this seems workable, but it takes time getting used to.
So, should we use the triangular grid for our miniature wargames? Honestly, I don't know yet. I will have to run a test game or two ... but any other experiences or insights are certainly welcome!