Can cell size be smaller than unit size?

  • February 2, 2018 at 05:36 #22721
    AlexPapa
    Participant

    In earlier posts I read that the cell size diameter must be as large as the unit diameter but that in later releases you would potentially support cell sizes smaller than the unit. Has this been added? The problem was discussed in this thread and it was mentioned there may be a solution in 2.1. Was this addressed or is does the requirement of grid size >= unit size remain?

    Problem with small cell size

    • This topic was modified 2 months, 2 weeks ago by AlexPapa.
    February 2, 2018 at 12:03 #22727
    Geminior
    Keymaster

    Apex Path has Clearance which allows for units larger than the cell size.
    There is one major limitation though, clearance will not work with multiple grids stitched together (using portals).

    February 3, 2018 at 03:10 #22735
    AlexPapa
    Participant

    Thanks for the info. Even with clearance enabled it seems there is an issue and wondering what you recommend. In the attached image the grid has a cell size of 1.0, the agent radius is 0.4 and the obstacle sensitivity range is 0.5. The clearance values for the cells around the bottom right corner of the yellow obstacle will all be 0.5, which means the unit will consider them valid for paths. This results in the unit bumping into that corner when the diagonal segment is traversed. What I described looks like a problem in general even unrelated to clearance. The center of the grids adjacent to the corners are slightly greater than the obstacle sensitivity range (0.5), so they are not blocked, but the diagonal path segment between them runs right by the corner which means unit of almost any size will collide with it. It seems path segments that have a point that’s within the obstacle sensitivity range should be blocked as well and not available for paths. It feels like that would obey the concept of object sensitivity. I assume this could be computationally expensive but wondering if it was considered. Do you see another way around this other than what I suggested? I realize the problem is reduced with a smaller grid size. This helps but the problems still exists. Also I realize that increasing obstacle sensitivity range or preventing diagonal moves would alleviate the issue but I don’t consider those good options for our use case. Another thing that exacerbates the problems when path smoothing is on. This smoothing causes deviation from the path even further which results in more bumping. Any guidance/suggestions is appreciated.

    Unit Colliding with Obstacle Corner

    • This reply was modified 2 months, 2 weeks ago by AlexPapa.
    • This reply was modified 2 months, 2 weeks ago by AlexPapa.
    February 14, 2018 at 10:33 #22804
    Rami
    Keymaster

    Hi Alexpapa,

    Sorry for not responding to your questions.

    Unfortunately I don’t have any other suggestions than what you have already yourself mentioned as solutions to alleviate the issue. Our lead developer, Geminior, is out with sickness currently but I will alert him to this post as soon as possible. Note however that I cannot guarantee that any ‘perfect’ solution exists for this situation as things are currently.

    February 14, 2018 at 10:59 #22807
    Geminior
    Keymaster

    There is a setting for this exact purpose. On the Path Options component, you will find ‘Allow Corner Cutting’.
    When that is enabled, unit’s will cut corners in the way you describe.
    When disabled it will only traverse diagonals when both cells perpendicular are unobstructed.

You must be logged in to reply to this topic.