need help with pathing for a circular defence map

The map I'm making is a 4 player map with a trench that goes in a donut (well actually its a rectangle) shape. I'm planning to order the units to move around to 4 points in the map, the problem is that if someone blocks the way, the units will go all the way backwards around the circle to get there, kinda like in wintermaul when a player hooks. I would prefer the units to just attack if they can't get through. How would I do this?

EDITed for grammar and spelling

Here's a somewhat dangerous way..

Once it reaches a point, set its mana (or perhaps custom value) to something. Make sure that point is a region that completely covers the path and is big enough to encompass that area..

Make another region completely covering the area the unit came from.. If it walks in there and its custom value is set to whatever, then it will say 'Unit- issue order attack move to blah blah' or 'Attack random building..'

Basically what will happen is this:

1: Unit walks through first region, custom value not set so nothing happens.

2: Unit reaches the point that tells the unit to turn and go to the next point- gets the custom value set - but its blocked.

3: It turns around, with custom value set, and walks through the other region.

4: The region detects the custom value and tells the unit to attack.


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Now its dangerous due to having players maze on the turn region, thus possibly sending a unit that CAN get through back through the other region-- telling it to attack.. That area would have to be all unbuildable.

And the second reason why that may not work is, even if you order the unit to attack-move, it still might go around.. A possible fix to this is to attack an actual building.

Overall, it's kind of a bad solution, but it may work.

That sounded good, and I was about to stick it in when I had an even better idea! All I had to do was add four oneway doors around the path. that should do it. thanks anyways norbo :þ