.. role:: blue
   :class: blue

MbTopologyItem Topological Object
=================================
.. _MbTopologyItem_Topological_Object_:

.. kernel version: 

The :blue:`MbTopologyItem` class is declared in the *topology_item.h* file.

The MbTopologyItem topological object differs from other topological
objects by having a **name**, a modification flag *changed*,
and a marker *label*. The MbTopologyItem topological object is a
derived class of the :ref:`MbTopItem <MbTopItem_Topological_Object_>` topological object.

.. figure:: /MODELER/TOPOLOGICAL_OBJECTS/pictures/O.7.1.1.png
   :width: 12cm
   :align: center

The :blue:`MbAttrContainer` attribute container endows named topological
objects with attributes.

The C3D geometric kernel implements the following topological objects
that are derived from the :blue:`MbTopologyItem` class:

:ref:`MbFace <MbFace_Face_>` -- face,

:ref:`MbEdge <MbEdge_Edge_>` -- edge,

:ref:`MbVertex <MbVertex_Vertex_>` -- vertex.

The :blue:`MbEdge` edge has a derived class :ref:`MbCurveEdge <MbCurveEdge_Face_Edge_>` --
a face-joining edge.

Named topological objects have the following methods:

methods that handle transformation of a topological object:

void :blue:`Move`\( const :blue:`MbVector3D` & **v**, MbRegTransform * iReg = NULL ),

void :blue:`Rotate`\( const MbAxis3D & **axis**, double **angle**, MbRegTransform * iReg = NULL ),

void :blue:`Transform`\( const :blue:`MbMatrix3D` & **m**, MbRegTransform * iReg = NULL ),

methods that handle the name of a topological object:

MbName & :blue:`GetName`\(),

SimpleName & :blue:`GetMainName`\(),

SimpleName & :blue:`GetFirstName`\(),

a method that returns a type from the enumeration of topological objects:

MbeTopologyType :blue:`IsA`\().

Named topological objects are used as elements for constructing
geometric model objects.