BoxCollider の Edit Collider のような UI

BoundingBoxSample.cs

using UnityEngine;

#if UNITY_EDITOR
using UnityEditor;
#endif

public class BoundingBoxSample : MonoBehaviour
{
    public Vector3 BoundingBoxCenter;
    public Vector3 BoundingBoxSize;
}

#if UNITY_EDITOR

public class BoundingBoxEditorScript
{
    [DrawGizmo(GizmoType.NonSelected | GizmoType.Active)]
    static void DrawExampleGizmos(BoundingBoxSample bb, GizmoType gizmoType)
    {
        var transform = bb.transform;
        Gizmos.color = new Color32(145, 244, 139, 210);

        var center = bb.BoundingBoxCenter;
        Gizmos.matrix = Matrix4x4.TRS(transform.TransformPoint(center), transform.rotation, transform.lossyScale);
        var scale = Vector3.Scale(bb.BoundingBoxSize, transform.lossyScale);
        Gizmos.DrawWireCube(Vector3.zero, scale);
    }
}


[CustomEditor(typeof(BoundingBoxSample))]
public class ExampleInspector : Editor
{
    void OnSceneGUI()
    {
        Tools.current = Tool.None;
        var bb = target as BoundingBoxSample;

        var transform = bb.transform;

        Handles.color = new Color(0f, 1f, 0f, 1f);

        EditorGUI.BeginChangeCheck();

        var plusXCenter = transform.TransformPoint(bb.BoundingBoxCenter + (bb.BoundingBoxSize.x / 2) * Vector3.right);
        Vector3 value = Handles.Slider(plusXCenter, transform.right, 0.1f, Handles.DotHandleCap, 1f);
        if (EditorGUI.EndChangeCheck())
        {
            var point = transform.InverseTransformPoint(value) - bb.BoundingBoxCenter;
            bb.BoundingBoxSize = new Vector3(point.x * 2, bb.BoundingBoxSize.y, bb.BoundingBoxSize.z);
        }
    }
}

#endif