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Top Down Sprite with the NavMeshAgent Issues

Discussion in '2D' started by alphamalet, Dec 29, 2013.

  1. alphamalet

    alphamalet

    Joined:
    May 1, 2013
    Posts:
    2
    I am attempting to make a top down 2D shooter with sprites, and need help getting everything to work correctly. My game will need pathfinding for its AI, and to accomplish this I am trying to use the Nav Mesh Agent. Doing this with Unity's 2D perspective appears to be impossible, since the Nav Mesh won't bake on a plane parallel to the Y axis. What I am trying to do instead is have a fixed top-down camera on the Y axis, and have my Game take place entirely on the X and Z axis(depicted in my pictures). This way I can bake a NavMesh and use the Nav Mesh Agent for my AI.

    To accomplish this I am using a GameObject with a box collider, a sprite renderer, and a NavMeshAgent

    Unfortunately I am not getting the desired results.

    Prior to playing the scene, it looks like this. Everything is the way it should be.
    $Screen shot 2013-12-29 at 6.30.34 PM.png

    When I play the scene, the sprite, and it's collider rotate perpendicularly to the ground, looking like this.
    $Screen shot 2013-12-29 at 6.32.08 PM.png

    Pathfinding behaves the way I intended it to by my script, but I don't want the NavMeshAgent to rotate my sprite renderer.

    Can anyone tell me how to stop the NavMeshAgent from rotating my GameObject, so that my sprite stays at the desired perspective.

    I have tried manually setting the GameObject's rotation, and that doesn't seem to work. I have also tried using this line of code in my script...

    GetComponent<NavMeshAgent>().updateRotation = false;

    ...and that doesn't seem to work either. Are there any suggestions? The game I'm making needs to be made in a crunch, so programming my own pathfinding isn't really an option, and I really want to pathfind through the NavMeshAgent since that's what I'm familiar with.
     
  2. alphamalet

    alphamalet

    Joined:
    May 1, 2013
    Posts:
    2
    This issue has been solved. I posted this question on reddit, and a user by the name of Finblast managed to find a solution for me. His response:

    Ah, finally a question I'm qualified to answer! (I'm currently making a top down game that is setup exactly the same way.) I quickly replicated your setup and I think I know what the problem is.
    You can't use the sprite renderer component on the same GO [Game Object] as the navmeshagent, since it's default rotation makes it face the Z-axis. You probably tried to rotate your GO around the X-axis by 90 degrees when setting it up to get it facing the camera. The thing is the navmeshagent component requires your GO's Y-axis to always point away from the floor, so when you play your scene it will reset any rotations you made in the inspector, if the Y-axis isn't pointing away from the floor normals.
    The solution is pretty simple. Make a new GameObject that handles the sprite rendering, instead of putting it in the same GO as the navmeshagent. Then make this new GO a child of the GO that has the navmeshagent on it. This way you can rotate it any way you like, and the navmeshagent won't reset it's rotation.
    EDIT: You probably don't want to mess around with NavMeshAgent.updateRotation, I think that only affects the Y-axis rotation, meaning if it's set to false your AI will never turn to face anything other than the initial direction.