A* Pathfinding Project

Make unreachable path traversible


#1

If I were to enclose a block with dynamic obstacles, how can I still have a path on the inner part of the block?

Here is a picture to describe better. I want the units to still be able to path inside.

Thanks! Great product!


#2

Is this even possible?


#3

Hi

Are you using a NavmeshCut here?
If so, you could use a custom mesh as the cut. Alternatively you could construct the border out of 4 smaller navmesh cuts.


#4

Yes, but These walls are dynamic and can be created and destroyed, quite a bit. They also could be any shape the user builds. Is that still viable? Is there any way to have it just always be walkable


#5

If they can be any shape I assume you have some way of defining the border of it? Then you can just put smaller NavmeshCuts around the border instead of covering the whole thing?


#6

Thanks for replying before you take off. Maybe you are correct, but I just wanted to clarify more.

I mean the player can build the wall in any shape. walls are just 1x1 squares that they can build around their units. Anytime I enclose the units within walls, the path becomes unwalkable, and the units inside pop out of the enclosed walls. I would want the units to still pathfinding inside these walls.

Each wall is a dynamic obstacle/unit with a selection ring. In the GIF I make a square, but it could be any shape the players decides. The walls also could be connected to a cliff, lets say. and the cliff is part of the closed border of the wall.


#7

That’s strange… Could you post a screenshot of how your navmesh looks after you have built it?

In the RTS example I can manage to position some navmesh cuts so that the units inside cannot move outside of it.
image


#8

What do you mean? I can, but can you explain what you need?

Once I enclose the units, the path becomes grey like in the picture of the first post. Before that everything is pathable.


#9

Also. You are saying dynamic obstacle all the time. Are you using a navmesh cut or something else? Is that hexagon button for re-scanning the graph?

If you are re-scanning the graph then possibly that region is smaller than the ‘Min Region Size’ in the recast graph settings and it is removed because of that.


#10

It is a navmesh cut. It is the barracks but reshaped to be a square.

The button just toggles building or moving units.

I am not re scanning. If I remove one square, the path fills in the area, so I thought it was updating fine.


#11

Okay… I’m not sure what could be going wrong here.
Are you getting any error messages?

You might want to expand your squares a tiny bit so that they overlap slightly. I think having them just touch each other should work well, but you never know with floating point errors.