Tutorial #1 steering object cuts corners


I’ve just bought the Pro license, and started with the “Getting Started” tutorial here http://www.arongranberg.com/astar/docs/getstarted.php

I’m seeing two issues:

  1. Occasionally the path creation never exists.
  2. The collision capsule cuts corners, intersecting geometry it shouldn’t.

I’ve made a video showing both issues: http://screenr.com/gTd7

You can see I have to start the app twice because the first time issue (1) happens; i.e. the path creation never completes, so nothing happens.

You can see the cutting-corners issue in the second part of the video. The collision capsule radius is 0.5, so a diameter of 1, and the A* component has its collision type set to capsule with a diameter of 2, yet the seeker collides with the obstacles. If I turn off “Cut Corners”, the issue still exists.

What am I doing wrong?



The getting started tutorial’s AI is not really that good, it just serves as a simple placeholder AI. What your example AI suffers from is that it picks the next waypoint too quickly which makes it cut corners. Try the AIPath component for a slightly better AI.

Not sure why your paths are not calculated. Is it repeatable? If so, could you send me a small example scene showing the issue so I can fix the eventual bug?


Ok, I’ll try AIPath. How will this help, though? Finding a waypoint, and steering through an unwalkable region to get there seem unrelated. If I understand what you’re saying is true, given a path of waypoints, A->B->C, as the object approaches B, it chooses C, but moves towards C through a non-pathfindable region.

As for the path calculation not exiting, it does it every few executions, so it’s fairly repeatable.

The AIPath steers towards a more correct direction to follow the path more exactly while still trying to not look so rigid. You could also try adding a Simple Smooth Modifier and using Bezier or Offset Curve modes.

Regarding path calculation: well, it never happens for me… If you could create a small example scene where the problem occurs and sent it to me that would be very helpful.