Simple Terrain-Only A-Star for TGE

Download Code File

These two files should be extracted to engine/ai.

Disclaimer

Well, this isnt the best pathfinding, and I suggest you look into the AI pack for torque that is going to be released at some stage if you want to do anything complex.

I have done quite a chunk of code C++ only, so it'd be a good idea to read and rewrite the code as you see fit. =)

Reference

After a recompile you have access to the following commands:

pathInit(); -- Starts the pathfinder, required to do any pathfinding.

pathCreate(); -- Forces the NavMap to be recreated (usually done by pathInit).

pathWrite(%file); -- Writes the NavMap to %file.

pathGetNextPoint(%start, %goal, %closed); -- The actual pathfinding command, start is a 3D location in the format of "x y z", so is goal. %closed is a NodePath that is populated by passing to this function. For a successful path, the same closed list must be passed each time.

pathSetMaxSlope(%slope) -- Sets the maximum climb, squared. The recommended value is 100.

Implementation

For a successful implementation, you must call pathInit and pathSetMaxSlope at the start of the game, and then call pathGetNextPoint for every pathfinding operation. It should be called at the start, and after each point is reached, other than the goal.

You should also edit aiPathfinding.cc if you arent using the RTS starter kit.

Check line 72 and read the comment.

Example

Here is a good example how to read all the points of a path:

pathInit();
pathSetMaxSlope(100);

%closed = new NodePath();

%start = "0 0 0";

%dest = "500 0 0";

%point = pathGetNextPoint(%start, %dest, %closed);

while(%point !$= %dest)
{
    echo(%point);
    %point = pathGetNextPoint(%point, %dest, %closed);
}