.. role:: code
   :class: code

Constructing a Deformable Block
===============================
.. _Construction_a_deformable_block_:

.. kernel version: 118058

The function

.. code-block:: cpp

   MbResultType NurbsBlockSolid( const MbPlacement3D &    place,
                                       double             ax,
                                       double             ay,
                                       double             az,
                                       bool               outDir,
                                 const MbSNameMaker &     names,
                                       SimpleName         name,
                                       NurbsBlockValues & param,
                                       MbSolid *&         result )

constructs a solid in the form of a rectangular parallelepiped with deformable faces.

The input parameters of the function are:

- **place** -- the local coordinate system;
- **ax** -- the size along the X axis;
- **ay** -- the size along the Y axis;
- **az** -- the size along the Z axis;
- **outDir** -- the orientation of face normals outward from the solid (*true* -- normals point outward);
- **names** -- the operation name maker;
- **name** -- the main name;
- **param** -- the face construction parameters (see :code:`NurbsBlockValues` struct in the file *op_shell_parameter.h*).

The output parameter of the function is the solid **result** built on NURBS surfaces.

The function is declared in the file *action_direct.h*.

The function constructs a deformable solid in the form of a rectangular parallelepiped whose dimensions in the local coordinate system **place** are defined by the parameters **ax**, **ay**, **az**. All faces of the parallelepiped are built on the basis of planar NURBS surfaces whose orders and numbers of control points are determined by the parameter **param**.

Figure shows the parallelepiped **result** constructed by the :code:`NurbsBlockSolid`\() function and its control points. The figure on the right shows the same parallelepiped after deformation by moving the face control points:

.. figure:: ../../pictures/M.6.4.1.png
   :width: 21cm
   :align: center

The :code:`NurbsBlockSolid`\() function adds the :code:`MbNurbsBlockSolid` builder to the construction history of the resulting solid. The builder stores all data required to perform the operation. The :code:`MbNurbsBlockSolid` builder is declared in the file *cr_nurbs_block_solid.h*.