Trigrids

What are Trigrids?

Trigrids are a new non-physical mapping system that allows for large-scale areas to be covered purely in the theatre of the mind without the need for a physical reference map.

Think of a regular map like a painting. It's detailed and beautiful, but very time-consuming to paint, and not everyone has the artistic skills do a large-scale painting while also DMing. A Trigrid is like a description of that painting. All of the information, but without the visual element.

What are they used for?

Tridgrids are great at mapping large-scale areas that TTRPGs typically struggle with. For example, cities, mega-dungeons, and world/region maps. Instead of having to spend painstaking hours drawing out a map for any of the above, now you can create easy reference points using a Trigrid.

How do they work?

Conventional TTRPG maps use what is called a Cartesian Plane. This is the same system used by real-world maps: a flat grid with two axes, X and Y, counting outward from a corner. This approach is commonly used for both square grids and hex maps.

While familiar, this system has its limitations. It requires you to know the exact dimensions of the map in advance, and in a TTRPG setting, it usually depends on having a physical reference image to visualise where locations are in relation to one another.

Trigrids is hex-based and uses a different approach called Cube Coordinates. Instead of two axes, it uses three: X, Y, and Z. Rather than beginning in a corner, mapping starts from the centre of the world, known as the World Hub or the Home tile.

From the World Hub, every hex is given a unique six-character coordinate that describes its position relative to the centre. Because all locations are defined in relation to this central point, the map can expand infinitely in any direction as exploration continues.

How is it done?

Each axis is assigned two letters to represent its positive and negative directions. 

For example, the X axis uses A for positive (X+) and B for negative (X−). 

The Y and Z axes follow the same pattern, continuing through the alphabet up to F. Positive positions are clockwise, negative positions are anti-clockwise relative to their axis (their line across the board.)

As a result, a typical hex might have a coordinate such as A1 D2 E1, which translates to X+1, Y−2, Z+1. The largest number in the coordinate always shows how many steps away from the World Hub you are, and is known as the ring coordinate.

If any coordinate shows as 0 and does not have a connected letter, then that means you are right on the axis line for that direction.

How do I find a specific coordinate?

To find a coordinate, first, decide the orientation of your hex grid: whether the hexes have a point facing up or a flat side. 

From the World Hub, three directions extend outward evenly, each separated by a single face of the hex. 

Then start at the World Hub and choose a hex. Each hex has three coordinates. Start with X, followed by Y, and then Z. To find what each coordinate is, check whether it is clockwise (positive) or anti-clockwise (negative) relative to its axis line. Then count how many tiles away it is from that line. 

This will give you something along the lines of A1 (X+1) or B1 (X-1). Repeat this process for all three axes, and you'll end up with something like A1, C2, and F4. (X+1 Y+2 Z-4).

What can you do with a coordinate?

Think of a hex coordinate like a street address. As a DM, when planning out your locations and encounters, you can give them this address. 

So when your party explores the world, they can find and locate that address relative to their position. Gone are the days of guessing how far the walk to the tavern is, or how many days of travel it takes to reach the dragon’s lair.

Furthermore, you can use Trigrids as a live mapping system. Because you start in the centre, and can expand out infinitely in any direction, players can uncover random events on each tile, and revisit those events as you create them.

This is most useful for mega-dungeons, where you want each layer to not only be unique, but also random. Allowing for a smooth path finding to and from where they begin and where they end up.

While we advise that the home tile is in the centre of the map, nothing is stopping you from using it at the edge and plotting out a path to your destination. For example, to locate the stairs to the next floor of the dungeon.

Closing thoughts

Trigrids are not intended to replace conventional maps. Using coordinates for tactical combat, where exact positioning matters, would be cumbersome and impractical. Instead, Trigrids excel at large-scale exploration, where drawing and maintaining a complete map would otherwise be time-consuming or impossible.

Try giving it a go. Though we strongly advise you learn to calculate the coordinates yourself, we also have two handy reference grids that should cover most areas. Or for a deeper, more nonlinear map, we also have our handy Trigrid calculator, which you can import/export maps from for quick use.

For more information on Cube Coordinates, look here:

Interactive Trigrid Calculator

Hold CTRL and drag to move. Hit export when you're done, and import to load in maps.