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
GfcSection
GfcParameterizedSection
1PositionGfcCoordinates2d
GfcRectangleSection
2XLengthGfcDouble
3YLengthGfcDouble
GfcRectangleHollowSection
4ThicknessGfcDouble
继承关系
GfcRoot
  └GfcSection
    └GfcParameterizedSection
      └GfcRectangleSection
        └GfcRectangleHollowSection