When You Wish Upon A*

Although Torque is an essentially complete game engine, it lacks one major component: AI. I'm sure you know what I'm talking about. You open the aiPlayer files and think, "Is this it? Where's the code that lets the bot, you know, try to kill me? Or even find me, for that matter?" Well, the first part is another subject for another day. The second part is where I decided to begin. The general consensus on the internet seemed to be that a* was the best and fastest pathfinding method, so that's what I chose. Using the information from this excellent article, I began. I won't go into the gory details of a* here, the article explains it better than I ever could. Now, a week later, I have a working (although far from finished) implementation.

Now, I know that there's another a* resource out there, but I still prefer to use my own. This is mostly because of flexibility. The other resource (part of the iAI engine) places nodes for the entire mission area, and only on the terrain. Of course, there are some major things iAI's a* system has that mine doesn't, like doing more than a castray to see if two points can be linked, realistic move costs, path smoothing, etc. However, mine is (at this point) mostly a proof-of-concept.

In my implementation, small grids of nodes are added with NavMesh objects, and the nodes are then linked together.

Because the nodes are stored separately from the NavMesh objects, a path can go across any number of objects without a performance drop. (I went over the path in red for clarity)

Some things I hope to add are
-smooth paths
-better walkability tests
-optimize
-track down the annoying bug where the paths are re-calculated 4 or 5 times when an object is moved
-add real AI

More screenshots and (hopefully) code to come!