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Gears Tactics A* Algorithm

Hi guys.

Pretty straightfoward, the subject says it all. I´d like to know how the A* pathfinding algorithm used in Gears of War tactics work. I am assuming they use some sort of A* algorithm since this is usually the way to go in terms of pathfinding in tactics games. Despite the fact that I know how an A* algorithm usually works, I am not sure how it does in this case. I think it has something to do with the nodes attached to every single object in the level (I call ¨nodes¨ to every single place in the level in which a character can take cover, that is, a wall, a box, a car, etc). Could any of you guys shed some ligh on the implementation details to achieve exactly the same effect as in Gears Tactics? I´d appreciate it, thanks.

Not familiar with the game, but there is an A* implementation built into UE4 already - FGraphAStar - and even a grid based approach to using it.
Additionally, a tutorial about replace the regular path finding with a grid based approach was recently update by Crussel:
Builtin A* Pathfinding in Unreal Engine 4.25

Hope that helps.

Thank you, it does help!

Can’t remember if they covered the pathfinding but this years Unreal Fest had a talk covering the AI in this game.

https://www.youtube.com/watch?v=rzR-…m&index=8&t=0s

Man, I love you, I think this is what I was looking for!!! (I´ve been looking for this for days now) Thank you!!

EDIT: Nope, it wasn´t what I was looking for, but it was very informative, and even if this doesn´t answer my question, it certainly helps in some other fronts.

No worries,sorry it doesn’t have what you were looking for. Glad it helped in other areas. I thought it was very good as giving an overview at how to approach this kind of AI.

I’m not really sure why you’re hung up A* with UE4. For you tactics map I’m sure you could preset some locations and use the preplanning phase to pick out locations in the level for various moves (cover, charge, retreat etc).

A simple location manager that lets you update location information (eg was it blown up) would work? (Programming Subsystems | Unreal Engine Documentation)

For what it is worth Tactics maps tend to be so small A-Star is both overkill and causes certain logic to be harder to express.

For TINY METAL we used a basic breadth first search. The upside being our “can unit pass through this other unit” logic was all in a single function for both the path generation and rule validation.