January 20, 2014

Porting the Pathfinding Unity Mecanim example to A-Star

While working on my project, I've looked at Mecanim for the animation of my AI agents. Here is my first try at using Mecanim with Aron Granberg A* Pathfinding Project.

step 1 : Take the "Nav Mesh Example" scene from Unity Mecanim Example Scenes.

step 2 : Import the free version of Aron Granberg A* Pathfinding in the project, and add a A* Pathfinding graph. For my test, I've used the 3.4.0.5 version, and I've added a GridGraph of 160 x 120 with a node size of 0.4 and with a center at 0;0;0.

step 3 : Create a script named AgentAStar.cs with the code linked.

step 4 : Modify the TeddyBear object from the scene. Remove the Agent script and the NavMeshAgent component. Add the Seeker and the SimpleSmoothModifier scripts from A* project and add the AgentAStar script described above.
It should look like that:

step 5: It's done! Run the scene and left click on the ground to move the bear.

Possible improvements:
- Add all Crates in an obstacle layer and mask it in the graph
- Tweak modifiers, node size, erosion ...etc.
- If you own the Pro version, you can use a recast Graph for better results.

If you have a better implementation or a different working code, feel free to post it on the official A* pathFinding forum.