Skip to content

Instantly share code, notes, and snippets.

@unitycoder

unitycoder/BoxColliderFitChildren.cs

Created April 23, 2024 08:38
Show Gist options

  • Select an option

    Learn more about clone URLs
  • Save unitycoder/d5f576d7ae43d14422ec6c94923b03a2 to your computer and use it in GitHub Desktop.

Select an option

Learn more about clone URLs
Save unitycoder/d5f576d7ae43d14422ec6c94923b03a2 to your computer and use it in GitHub Desktop.
Download ZIP

Revisions

  1. unitycoder created this gist Apr 23, 2024.
    48 changes: 48 additions & 0 deletions BoxColliderFitChildren.cs
    View file
    Original file line number Diff line number Diff line change
    @@ -0,0 +1,48 @@
    // https://github.com/UnityCommunity/UnityLibrary/blob/master/Assets/Scripts/Editor/ContextMenu/BoxColliderFitChildren.cs

    // Adjust Box Collider to fit child meshes inside
    // Usage: You have empty parent transform, with child meshes inside, add box collider to parent then use this
    // NOTE: Doesnt work if root transform is rotated

    using UnityEngine;
    using UnityEditor;

    namespace UnityLibrary
    {
    public class BoxColliderFitChildren : MonoBehaviour
    {
    [MenuItem("CONTEXT/BoxCollider/Fit to Children")]
    static void FixSize(MenuCommand command)
    {
    BoxCollider col = (BoxCollider)command.context;

    // record undo
    Undo.RecordObject(col.transform, "Fit Box Collider To Children");

    // get child mesh bounds
    var b = GetRecursiveMeshBounds(col.gameObject);

    // set collider local center and size
    col.center = col.transform.root.InverseTransformVector(b.center) - col.transform.position;
    col.size = b.size;
    }

    public static Bounds GetRecursiveMeshBounds(GameObject go)
    {
    var r = go.GetComponentsInChildren<Renderer>();
    if (r.Length > 0)
    {
    var b = r[0].bounds;
    for (int i = 1; i < r.Length; i++)
    {
    b.Encapsulate(r[i].bounds);
    }
    return b;
    }
    else // TODO no renderers
    {
    return new Bounds(Vector3.one, Vector3.one);
    }
    }
    }
    }