.. role:: blue
   :class: blue

Boolean Operation on Bodies
===========================
.. _Boolean_Operation_on_Bodies_:

.. версия ядра: 118053

The function

.. code-block:: cpp

   MbResultType BooleanResult( const c3d::SolidSPtr &           solid1,
                                     MbeCopyMode                sameShell1,
                               const c3d::SolidSPtr &           solid2,
                                     MbeCopyMode                sameShell2,
                               const MbBooleanOperationParams & params,
                                     c3d::SolidSPtr &           result );

constructs a new body by executing a Boolean operation on two solids with the ability to control face and edge merging.

The function input parameters are:

- **solid1** — the first solid for the Boolean operation;
- **sameShell1** — the copy mode for the first solid;
- **solid2** — the second solid for the Boolean operation;
- **sameShell2** — the copy mode for the second solid;
- **params** — the parameters of the Boolean operation.

The function output parameter is the **result** object containing the constructed solid.

The function returns a result code from the :blue:`MbResultType` enumeration (see *mb_operation_result.h*).

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

The function performs union, intersection and difference operations on two solids **solid1** and **solid2**.

The parameters **sameShell1** and **sameShell2** control the transfer of faces, edges and vertices from the source solids **solid1** and **solid2** to the constructed solid **result**, and can take one of four values:

- *cm_Same* = 0 (the shell is not copied);
- *cm_KeepHistory* (the source shell and its copy share common base surfaces, vertices, and faces unchanged by the operation);
- *cm_KeepSurface* (the source shell and its copy share common base surfaces);
- *cm_Copy* (the source shell and its copy do not share any common data).

A detailed description of the :blue:`MbeCopyMode` enumeration is provided in section :ref:`Copying a Set of Faces <Copying_a_Set_of_Faces_>`.

The class :blue:`MbBooleanOperationParams` contains parameters for executing the Boolean operation. When creating an object of class :blue:`MbBooleanOperationParams`, one of the following constructors is used:

.. code-block:: cpp

   MbBooleanOperationParams(      OperationType       oType,
                            const MbBooleanFlags &    flags,
                            const MbSNameMaker &      operNames,
                                  ProgressIndicator * progress = nullptr )

   MbBooleanOperationParams(      OperationType        oType,
                                  bool                 closed,
                            const MbSNameMaker &       operNames,
                                  IProgressIndicator * progress = nullptr )

where

- **oType** — the type of Boolean operation;
- **flags** — control flags for the Boolean operation;
- **operNames** — name maker;
- **closed** — indicator of closure of the operand shells;
- **progress** — progress indicator for operation execution.

The variant of :blue:`MbBooleanOperationParams` object with the **closed** parameter works only for non-closed solids and specifies the need to check the result for closure.

The parameter **oType** defines the type of Boolean operation and can take three values: *bo_Union*, *bo_Intersect*, *bo_Difference*:

- when **oType** = *bo_Union*, the function performs union of solids **solid1** and **solid2**;
- when **oType** = *bo_Intersect*, the function performs intersection of solids **solid1** and **solid2**;
- when **oType** = *bo_Difference*, the function performs subtraction of **solid2** from **solid1**.

The parameter **operNames** is used for naming resulting objects of the Boolean operation.

The parameter **flags** contains control flags for the Boolean operation.

The object has the following flags, which can be set in the constructor when creating the object, or using separate setter functions:

:blue:`bool` **mergeFaces** — merge similar faces;

:blue:`bool` **mergeEdges** — merge similar edges;

:blue:`bool` **closed** — closure of the operand shells;

:blue:`bool` **enclosureCheck** — check shells for nesting;

:blue:`bool` **allowNonIntersecting** — output the resulting shell if there are no intersections;

:blue:`bool` **cutting** — shell cutting flag when building cuts and sections;

:blue:`bool` **repairShellEdges** — shell edge repair flag for source shells.

Figure 1 shows the source solids **solid1** and **solid2**:

.. figure:: /MODELER/OPERATIONS_ON_BODIES/pictures/M.2.1.1.png
   :width: 12cm
   :align: center

   Рис. 1

Figure 2 shows the result of the Boolean union operation on solids **solid1** and **solid2** shown in Fig. 1:

.. figure:: /MODELER/OPERATIONS_ON_BODIES/pictures/M.2.1.2.png
   :width: 12cm
   :align: center

   Рис. 2

Figure 3 shows the result of the Boolean intersection operation on solids **solid1** and **solid2** shown in Fig. 1:

.. figure:: /MODELER/OPERATIONS_ON_BODIES/pictures/M.2.1.3.png
   :width: 12cm
   :align: center

   Рис. 3

Figure 4 shows the result of the Boolean difference operation (subtracting **solid2** from **solid1**) on the solids shown in Fig. 1:

.. figure:: /MODELER/OPERATIONS_ON_BODIES/pictures/M.2.1.4.png
   :width: 12cm
   :align: center

   Рис. 4

Figure 5 shows the result of the Boolean difference operation (subtracting solid **solid1** from solid **solid2**) on the solids shown in Fig. 1:

.. figure:: /MODELER/OPERATIONS_ON_BODIES/pictures/M.2.1.5.png
   :width: 12cm
   :align: center

   Рис. 5

To demonstrate the function's operation with an :blue:`MbBooleanFlags` object with different values of the *mergeFaces* flag, consider Boolean operations on source solids **solid1** and **solid2** shown in Fig. 6:

.. figure:: /MODELER/OPERATIONS_ON_BODIES/pictures/M.2.1.6.png
   :width: 12cm
   :align: center

   Рис. 6

Figure 7 shows the result of the union of solids **solid1** and **solid2** when the function operates with the flag *mergeFaces* = *true*:

.. figure:: /MODELER/OPERATIONS_ON_BODIES/pictures/M.2.1.7.png
   :width: 12cm
   :align: center

   Рис. 7

Figure 8 shows the result of the union of solids **solid1** and **solid2** when the function operates with the flag *mergeFaces* = *false*. Coinciding faces in Fig. 8 are not merged:

.. figure:: /MODELER/OPERATIONS_ON_BODIES/pictures/M.2.1.8.png
   :width: 12cm
   :align: center

   Рис. 8

Figure 9 shows the result of the difference operation (subtracting **solid2** from **solid1**) when the function operates with the parameter *mergeFaces* = *true* (merge similar faces):

.. figure:: /MODELER/OPERATIONS_ON_BODIES/pictures/M.2.1.9.png
   :width: 12cm
   :align: center

   Рис. 9

Figure 10 shows the result of the difference operation (subtracting **solid2** from **solid1**) when the function operates with the parameter *mergeFaces* = *false*. Coinciding faces in Fig. 10 are not merged:

.. figure:: /MODELER/OPERATIONS_ON_BODIES/pictures/M.2.1.10.png
   :width: 12cm
   :align: center

   Рис. 10

The function :blue:`BooleanResult`\() adds to the constructed solid's history log a builder :blue:`MbBooleanSolid`, which contains all the necessary data to execute the operation. The builder :blue:`MbBooleanSolid` is declared in the file *cr_boolean_solid.h*.

Test.exe application executes Boolean operations on bodies using Create→Solid→As union with a solid→Solid, Create→Solid→As subtraction with a solid→Solid, Create→Solid→As intersection with a solid→Solid menu commands.