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\page create_explode_page Explode

To \b Explode an object into sub-shapes, in the <b>Main Menu</b>
select <b>New Entity > Explode</b>. This operation opens the
<b>Sub Shapes Selection</b> dialog box.

\image html neo-obj1.png

To create a list of  sub-shapes (vertices, edges, wires etc.) of the
given shape using the \b Explode operation, you need to define the <b>Main
Object</b>, which will be exploded and the <b>Type of Sub-shapes</b> you wish to
obtain from it.

The \b Result of the operation will be a List of \b GEOM_Objects
(vertexes, edges, wires, faces, shells or solids).

Available choices in the <b>Sub Shapes Type</b> combo box depend on the type
of selected <b>Main Object</b>:
- \b Compound: to extract compounds;
- \b Compsolid: to extract compsolids;
- \b Solid: to extract solids;
- \b Shell: to extract shells;
- \b Face: to extract faces;
- \b Wire: to extract wires;
- \b Edge: to extract edges;
- \b Vertex: to extract vertices;
- \b Shape: to extract top-level contents of the compound shape;
- \b Flat: to extract "flat" contents of the compound shape.

Note: "flat" contents means top-level simple-type sub-shapes extracted from
the compound object recursively (i.e. there is no compounds in the result).
For example, if a compound C1 contains a solid S1 and another compound C2 that
contains solids S2 and S3 (see picture below):
- Explode operation with \b Shape type given as parameter will return S1 and C2;
- Explode operation with \b Flat type given as parameter will return S1, S2 and S3.

\image html flat_contents.png

Switching on <b>Select Sub-shapes</b> check box allows manual selection of sub-shapes
to be extracted from the main object. In this mode the user can select sub-shapes
directly in 3D viewer.

When <b>Select Sub-shapes</b> check box is switched on, additional \b Filter controls
allow to automatically pick up entites which satisfy specified threshold value(s).
The numerical functor for each sub-shape that is compared with threshold value(s)
is computed according to the shape's topological properties:
- length for edges and wires
- area for faces and shells
- volume for solids, compounds, compsolids

Filtering capabilities are not available for vertices.

In order to filter out some entities:
- Activate one or two filtering controls by switching on corresponding check boxes;
- Select required threshold comparator type; the following choices are available:
  - <b>Less Than</b> or <b>Equal or Less Than</b> for the first comparator;
  - <b>Greater Than</b> or <b>Equal or Greater Than</b> for the second comparator;
- Enter required threshold value (values);
- Press \b Apply button in the \b Filter group.

The entities which satisfy entered filtering parameters will be automatically highlighted
in the 3D viewer.

Using <b>TUI Commands</b> you can perform this operation in a
variety of ways:
- <em>geompy.ExtractShapes(Shape, Type, isSorted)</em> explodes a
  Shape into sub-shapes of a given Type and returns a List of sub-shapes.
  This method does not return the Shape itself if it matches the
  Type.
- <em>geompy.SubShapeAll(Shape, Type)</em> explodes a Shape on
  sub-shapes of a given Type and returns a List of sub-shapes.
- <em>geompy.SubShapeAllIDs(Shape, Type)</em> explodes a Shape on
  sub-shapes of a given Type and returns a List of IDs of
  sub-shapes.
- <em>geompy.SubShapeAllSortedCentres(Shape, Type)</em> explodes a
  shape on sub-shapes of a given type and sorts them taking into account
  their gravity centers, to provide stable order of sub-shapes.
  It returns a list of sub-shapes.
- <em>geompy.SubShapeAllSortedCentresIDs(Shape, Type)</em> explodes
  a shape on sub-shapes of a given type and sorts them taking into
  account their gravity centers, to provide stable order of sub-shapes.
  It returns a List of IDs of sub-shapes.
- <em>geompy.SubShape(Shape, Type, ListOfInd)</em> allows to obtain
  a compound of sub-shapes of  the Shape,  selected by they indices in a
  list of all sub-shapes of the given Type. Each index is in the range
  [1, Nb_Sub-Shapes_Of_Given_Type].
- <em>geompy.SubShapeSortedCentres(Shape, Type, ListOfInd)</em>
  allows to obtain a compound of sub-shapes of the Shape, selected by
  they indices in sorted list of all sub-shapes of the given Type. Each
  index is in the range [1, Nb_Sub-Shapes_Of_Given_Type]

<b>Arguments: </b>1 SHAPE + 1 type of SubShape.

<b>Example:</b>

\image html explode.png "A box, exploded into faces"

*/