Inspector上でVector3の各成分を(0,1)に制限するの続きです。
パラメータを追加することで(0,1)だけではなく(min,max)にすることも可能です。

UserAttributes.cs

using UnityEngine;
# if UNITY_EDITOR
using UnityEditor;
# endif
/// <summary>
/// Vector2/3を(min.max)に制限する <-<summary>を入れるとマウスオーバーで説明が出ます
/// </summary>
public class ClampVectorAttribute : PropertyAttribute {
    public float min;
    public float max;
    public ClampVectorAttribute(float min, float max)
    {
        this.min = min;
        this.max = max;
    }
}

# if UNITY_EDITOR
[CustomPropertyDrawer(typeof(ClampVectorAttribute))]
public class ClampVectorDrawer : PropertyDrawer
{
    // Necessary since some properties tend to collapse smaller than their content
    public override float GetPropertyHeight(SerializedProperty property, GUIContent label)
    {
        return EditorGUI.GetPropertyHeight(property, label, true);
    }

    // Draw a disabled property field
    public override void OnGUI(Rect position, SerializedProperty property, GUIContent label)
    {
        ClampVectorAttribute attr = (ClampVectorAttribute)attribute;
        switch (property.type)
        {
            case "Vector2":
                property.vector2Value = new Vector2(
                    Mathf.Clamp(property.vector2Value.x, attr.min,attr.max),
                    Mathf.Clamp(property.vector2Value.y, attr.min, attr.max)
                );
                break;
            case "Vector3":
                property.vector3Value = new Vector3(
                    Mathf.Clamp(property.vector3Value.x, attr.min, attr.max),
                    Mathf.Clamp(property.vector3Value.y, attr.min, attr.max),
                    Mathf.Clamp(property.vector3Value.z, attr.min, attr.max)
                );
                break;
        }
        EditorGUI.PropertyField(position, property, label, true);
    }
}
# endif