# Random wandering toward goal destination

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### #1tron_thomas

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Posted 07 February 2011 - 04:23 AM

I have a situation where there are numerous objects that need to wander about on a 2D plane. The objects should avoid certain areas in the plane and should also eventually make their way toward a desired goal destination.

Where can I find resources that would help with implementing this type of behavior?

### #2Reedbeta

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Posted 07 February 2011 - 04:37 AM

First of all, google for "pathfinding" and in particular "A* search", which is very handy anytime you need things to move around and avoid obstacles.

If you want things to wander randomly, you could try an approach like: pick a random point within a certain radius (excluding points in obstacles) and path to it. When you get there, pick another random point and repeat.

To make them gradually head toward a goal, every few iterations you could substitute the randomly chosen destination with the goal itself, but then only let them travel a short distance before re-randomizing the goal point. Depending on the obstacle geometry there's no guarantee they wouldn't get stuck in a steady state far from the goal, though.
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### #3tron_thomas

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Posted 07 February 2011 - 04:45 AM

I have the basic wandering around in a random way figured out.

I have tried using Google to find something that would be useful, and have not run across anything. That is why I'm now posting to this forum.

I don't think I need to resort to something as complicated as A* to solve this problem. I'm not interested in finding an optimal path from a source to destination.

I'm hoping to find something dealing with areas that can attract or repel as object move close to those areas.

### #4rouncer

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Posted 07 February 2011 - 05:30 AM

a* isnt complicated.

if you still dont want it, why not just weight their random movements towards the goal, and theyll get there eventually? is that what you want?
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Posted 07 February 2011 - 01:20 PM

What kind of wandering?

Independent, directed human-like "wandering" (say, people in a city each with their own objective), crowded path (like filing into a stadium), or like a flock of birds (chaotic "follow the leader")?

This may help:
http://opensteer.sourceforge.net/
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### #6tron_thomas

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Posted 08 February 2011 - 03:50 AM

They are supposed to be zombies wandering around in a court yard and slowly making their way into building.

### #7fireside

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Posted 08 February 2011 - 05:18 AM

You could pick random directions that have to more or less point toward the door and shift them in random amounts of time. You would need an avoidance system, though.
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Posted 08 February 2011 - 12:25 PM

http://www.red3d.com...PathFollow.html
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