[Bug]: Multi cell tokens' Terrain Modifiers are applied to their own movement

[nicholascain]

Describe the Bug

Multi-cell tokens that have Terrain Modifiers set will be affected by those modifiers when they are moved. This makes the behavior of large creatures that have modifiers unintuitive, and manual corrections need to be made, which can be confusing if there are other sources of Terrain Modifiers in the Object or Background layers.

To Reproduce

1. Create a multi-cell token
2. Give it a Terrain Modifier of, for example, Add 5.0
3. Drag it a space or two and see the movement cost

Expected Behaviour

If a creature token is using Terrain Modifiers (for example, using D&D 5e's rules where a creature's space is difficult terrain), large creatures should not have reduced speed due to their size. When calculating the cost to enter a space, a token's own Terrain Modifiers should be ignored.

Screenshots

In my setup, each cell costs 5 units of movement, and each of the example tokens have a Terrain Modifier of Add 5.0. I also have diagonals set to One-Two-One.

Moving a 4-cell token: note that the first move, in which its back half is entering cells its front half currently occupies, costs 10 units, while each other move costs 5 units.

The problem is worse with larger tokens. Note how this move of 10 units costs 20 units.

If I attempt to move one more cell, it will route around the issue in an unintuitive way. In fact, this route completely ignores Terrain Modifiers, but it doesn't make sense why it's necessary.

With still larger tokens, weirder still. It ignores Terrain Modifiers up until the last diagonal move (moving one additional space routes like the previous screenshot; no Terrain Mods and just delays its downward diagonal).

MapTool Info

Version 1.11.4

Desktop

Windows 10

Additional Context

Maybe related to this issue: https://github.com/RPTools/maptool/issues/2724