private void Init()
{
if (this.m_PreviewUtility == null)
{
this.m_PreviewUtility = new PreviewRenderUtility();
this.m_PreviewUtility.m_CameraFieldOfView = 30f;
this.m_Material = EditorGUIUtility.GetBuiltinExtraResource(typeof(Material), "Default-Material.mat") as Material;
this.m_WireMaterial = CreateWireframeMaterial();
}
}