A simple module for Foundry VTT which sets the grid to use alternating diagonals.

This Foundry VTT module allows you to apply the alternate diagonals rule to a game system, notably the "Simple World-Building" system.

"Alternate diagonals" is a grid-based rule where every other diagonal square costs double, sometimes referred to as the 1-2-1 diagonal rule.

This is the standard for Pathfinder 2nd Edition, where the first diagonal square costs 5ft of movement, the second 10ft, the third 5ft, and so on.

The code for calculating diagonal movement has been adapted from D&D5e for Foundry VTT.

Either search for and install this module within Foundry VTT, or copy this address into the Manifest URL bar:

https://raw.githubusercontent.com/AnthonyEdmonds/alternate-diagonals/main/module.json

Once enabled, this module should automatically set all grid interactions to use alternate diagonals.

This module may not work with game systems which already implement their own movement rules.

If you encounter any problems, raise a ticket on Github and I'll take a look.