2 .. _reorient_faces_page:
8 This operation allows fixing the orientation of a set of faces in the following ways:
10 * The required orientation of a set of neighboring faces can be defined by a vector giving the direction of a normal to a certain face. Since the direction of face normals in the set can be even opposite, it is necessary to specify a *control* face, the normal to which will be compared with the vector. This face can be either:
11 * found by proximity to a given point, or
12 * specified explicitly.
13 * The required orientation is given by faces of specified reference groups or/and sub-meshes. The reference groups can be omitted, then orientation of an arbitrary selected face to orient defines common orientation.
14 * Alternatively, the faces can be oriented relatively to the adjacent volumes.
16 The orientation of a face is changed by reverting the order of its nodes.
18 *To set orientation of faces:*
20 .. |imgfac| image:: ../images/reorient_faces_face.png
21 .. |imgpnt| image:: ../images/reorient_faces_point.png
22 .. |imggrp| image:: ../images/reorient_faces_ref_groups.png
23 .. |imgvol| image:: ../images/reorient_faces_volume.png
25 #. In the **Modification** menu select **Reorient faces** item or click *"Reorient faces"* button |imgfac| in the toolbar.
26 #. In the "Reorient faces" dialog box
28 * Select a way to define orientation:
30 * |imgpnt| - by specifying a point and a vector
31 * |imgfac| - by specifying a face and a vector
32 * |imggrp| - by specifying reference face groups
33 * |imgvol| - by specifying reference volume groups
35 * Select the **Object(s)** (mesh, groups and/or sub-meshes) containing faces to reorient, in the Object Browser or in the 3D Viewer.
36 * To reorient by direction of the face normal:
38 * Specify the coordinates of the **Point** by which the control face will be found. You can specify the **Point** by picking a node in the 3D Viewer or selecting a vertex in the Object Browser.
39 * Set up the **Direction** vector to be compared with the normal of the control face. There are following options:
41 * adjust vector components directly;
42 * select a vertex in the Object Browser or a node in the 3D Viewer; their coordinates will define vector components;
43 * pick two nodes (holding Shift button), the **Direction** vector will go from the first to the second node.
45 .. image:: ../images/reorient_2d_point.png
49 The orientation of adjacent faces is chosen according to a vector. The control face is found by point.
51 * In the second mode it is possible to pick the **Face** by mouse in the 3D Viewer or directly enter the **Face** ID in the corresponding field.
53 .. image:: ../images/reorient_2d_face.png
57 The orientation of adjacent faces is chosen according to a vector. The control face is explicitly given.
60 * In the third mode, the faces can be reoriented equally to reference faces:
62 * If necessary, select 2D **Reference objects** (groups or/and sub-meshes) containing the reference faces, in the Object Browser or in the 3D Viewer. This field can be left empty, then orientation of an arbitrary face will be used as a reference.
65 .. image:: ../images/reorient_2d_refgroup.png
69 The orientation of faces is given by reference face groups and/or sub-meshes.
71 * In the fourth mode, the faces can be reoriented according to volumes:
73 * Select an object (mesh, sub-mesh or group) containing reference **Volumes**, in the Object Browser or in the 3D Viewer.
74 * Specify whether face normals should point outside or inside the reference volumes using **Face normal outside volume** check-box.
76 .. image:: ../images/reorient_2d_volume.png
80 The orientation of faces is chosen relatively to adjacent volumes.
82 #. Click the **Apply** or **Apply and Close** button to confirm the operation.
84 **See Also** a sample TUI Script of a :ref:`tui_reorient_faces` operation.