Off-mesh connection links not removed between layers in the same tile location about recastnavigation HOT 7 CLOSED

I think the check can indeed be removed without any side effects - it was based on the assumption that all external links would have side != 0xff. However, after layers were introduced, I think this is no longer the case.
On the other hand it suffices to check that the link reference is to the target tile, as this will be true for external links only. I'm just not sure why the problem only occurs with off-mesh connections, and not regular external links between layers (for example due to stairs).

@memononen can you confirm if my understanding is correct?

from recastnavigation.

I think the check is valid, 0xff == this tile. The problem could potentially be also in connectExtOffMeshLinks. I recommend to double check all the side == -1 cases, those cases should connect off-mesh links between layers inside same tile location.

from recastnavigation.

Indeed, the off-mesh links between layers are connected with side = 0xff from here (connectExtOffMeshLinks is called with side = -1 from here). However, there is no similar mechanism in removeTile to remove these links again. The external links are removed here and the check @Sandern is referencing then indeed prevents those off-mesh connections between layers from being removed (here, for posterity).

Is checking that side != 0xff not redundant? Can there be external links within the same tile?
EDIT: Or a better way to ask - can there be links to a different tile or layer that are not external?

from recastnavigation.

Looks like tile internal off-mesh links also get side = 0xff. I think that explains skipping those links. So I'd say it is safe to remove tile->links[j].side != 0xff.

from recastnavigation.

I may have misunderstood this. I read it as if the problem was that off mesh connections between layers in the same tile location were not being disconnected. Reading the code, it looks like any external link between layers in the same tile location are connected with side = 0xff, so indeed these are not disconnected.

@Sandern Did I misunderstand? Can you clarify what you mean by tiles in the same layer?

from recastnavigation.

@JanielS You are right, description was not correct. It's between layers in the same tile location.

from recastnavigation.

PR is at #139 for it. Thanks for the report!

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