Extrusion
*********
-Extrusion is used to build mesh elements of plus one dimension than the input ones. Boundary elements around generated mesh of plus one dimension are additionally created. All created elements can be automatically grouped. Extrusion can be used to create a :ref:`extrusion_struct`:"structured mesh from scratch".
+Extrusion is used to build mesh elements of plus one dimension than the input ones. Boundary elements around generated mesh of plus one dimension are additionally created. All created elements can be automatically grouped. Extrusion can be used to create a :ref:`structured mesh from scratch <extrusion_struct>`.
.. image:: ../images/extrusion_box.png
:align: center
.. centered::
- "If you extrude several quadrangles, you get exactly the same mesh as if you meshed a geometrical box (except for that the initial quadrangles can be incorrectly oriented): quadrangles and segments are created on the boundary of the generated mesh"
+ If you extrude several quadrangles, you get exactly the same mesh as if you meshed a geometrical box (except for that the initial quadrangles can be incorrectly oriented): quadrangles and segments are created on the boundary of the generated mesh
Any node, segment or 2D element can be extruded. Each type of elements is extruded into a corresponding type of result elements:
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.. centered::
- "Two triangles extruded: no vertical rib segments generated from nodes #2 and #3 as they are shared by both triangles"
+ Two triangles extruded: no vertical rib segments generated from nodes #2 and #3 as they are shared by both triangles
-**To use extrusion:**
+*To use extrusion:*
-#. From the **Modification** menu choose the **Extrusion** item or click **"Extrusion"** button in the toolbar.
+.. |img| image:: ../images/image91.png
+.. |sel_img| image:: ../images/image120.png
- .. image:: ../images/image91.png
- :align: center
-
- .. centered::
- **"Extrusion" button**
+#. From the **Modification** menu choose the **Extrusion** item or click *"Extrusion"* button |img| in the toolbar.
- The following dialog will appear:
+ The following dialog will appear:
.. image:: ../images/extrusionalongaline1.png
:align: center
-
#. In this dialog:
- * Use *Selection* button to specify what you are going to select at a given moment, **Nodes**, **Edges** or **Faces**.
- .. image:: ../images/image120.png
- :align: center
-
- .. centered::
- **"Selection" button**
+ * Use *Selection* button |sel_img| to specify what you are going to select at a given moment, **Nodes**, **Edges** or **Faces**.
* Specify **Nodes**, **Edges** and **Faces**, which will be extruded, by one of following means:
* **Select the whole mesh, sub-mesh or group** activating the corresponding check-box.
* Choose mesh elements with the mouse in the 3D Viewer. It is possible to select a whole area with a mouse frame.
* Input the element IDs directly in **Node IDs**, **Edge IDs** and **Face IDs** fields. The selected elements will be highlighted in the viewer, if the mesh is shown there.
- * Apply Filters. **Set filter** button allows to apply a filter to the selection of elements. See more about filters in the :ref:`filtering_elements`:"Selection filters" page.
+ * Apply Filters. **Set filter** button allows to apply a filter to the selection of elements. See more about filters in the :ref:`filtering_elements` page.
* If the **Extrusion to Distance** radio button is selected
* specify the translation vector by which the elements will be extruded.
:align: center
.. centered::
- "'Along average normal' activated (to the left) and deactivated (to the right)"
+ 'Along average normal' activated (to the left) and deactivated (to the right)
* **Use only input elements** check-box specifies what elements will be used to compute the average normal.
- * If it is *activated* only selected faces, among faces sharing the node, are used to compute the average normal at the node.
- * Else all faces sharing the node are used.
- The picture below shows a cross-section of a 2D mesh the upper plane of which is extruded with **Use only input elements** activated (to the left) and deactivated (to the right).
+ * If it is *activated* only selected faces, among faces sharing the node, are used to compute the average normal at the node.
+ * Else all faces sharing the node are used.
+
+ The picture below shows a cross-section of a 2D mesh the upper plane of which is extruded with **Use only input elements** activated (to the left) and deactivated (to the right).
.. image:: ../images/extrusionbynormal_useonly.png
:align: center
.. centered::
- "'Use only input elements' activated (to the left) and deactivated (to the right)"
+ 'Use only input elements' activated (to the left) and deactivated (to the right)
+ .. |add| image:: ../images/add.png
+ .. |rm| image:: ../images/remove.png
+
* Specify the **Number of steps**.
* Optionally specify **Scale Factors**. Each scale factor in the list is applied to nodes of a corresponding extrusion step unless **Linear Variation of Scale Factors** is checked, is which case the scale factors are spread over all extrusion steps.
* **Scaling Center** can be defined either using spin boxes or by picking a node in the Viewer or by picking a geometrical vertex in the Object Browser.
- * **Add** button adds a scale factor to the list.
-
- .. image:: ../images/add.png
- :align: center
-
- .. centered::
- **"Add" button**
-
- * **Remove** button removes selected scale factors from the list.
-
- .. image:: ../images/remove.png
- :align: center
-
- .. centered::
- **"Remove" button**
-
-
+ * **Add** button |add| adds a scale factor to the list.
+ * **Remove** button |rm| removes selected scale factors from the list.
* If you activate **Generate Groups** check-box, the **result elements** created from **selected elements** contained in groups will be included into new groups named by pattern "<old group name>_extruded" and "<old group name>_top". For example if a selected quadrangle is included in *g_Faces* group (see figures below) then result hexahedra will be included in *g_Faces_extruded* group and a quadrangle created at the "top" of extruded mesh will be included in *g_Faces_top group*.
.. image:: ../images/extrusion_groups_res.png
:align: center
- This check-box is active only if there are some groups in the mesh.
+ This check-box is active only if there are some groups in the mesh.
:align: center
.. centered::
- "A node is extruded into a line of segments"
+ A node is extruded into a line of segments
.. image:: ../images/image76.jpg
:align: center
.. centered::
- "The line of segments is extruded into a quadrangle mesh"
+ The line of segments is extruded into a quadrangle mesh
.. image:: ../images/image77.jpg
:align: center
.. centered::
- "The quadrangle mesh is revolved into a hexahedral mesh"
+ The quadrangle mesh is revolved into a hexahedral mesh
**See Also** a sample TUI Script of an :ref:`tui_extrusion` operation.
