实体定义
属性定义
序号属性名称中文解释数据类型必填
GfcRoot
GfcConnectionGeometry
GfcConnectionSurfaceGeometry
1SurfaceOnRelatingElementGfcSurface
2SurfaceOnRelatedElementGfcSurface
继承关系
GfcRoot
  └GfcConnectionGeometry
    └GfcConnectionSurfaceGeometry