--- /dev/null
+.. _add_node_on_face_page:
+
+*****************************
+Cutting a face into triangles
+*****************************
+
+This operation cuts a face into triangles by adding a node on the face and connecting the new node with face nodes.
+
+ .. image:: ../images/add_node_on_face.png
+ :align: center
+
+*To cut a face:*
+
+.. |img| image:: ../images/mesh_split_face_interactive.png
+
+#. Select a mesh and display it in the 3D Viewer.
+#. In the **Modification** menu select the **Add node to triangle** item or click *"Add node to triangle"* button |img| in the toolbar.
+
+ The following dialog box will appear:
+
+ .. image:: ../images/add_node_on_face-dlg.png
+ :align: center
+
+
+#. Enter an **ID** of the face to split either by picking it in the 3D viewer or by typing its ID.
+
+#. Press *Selection* button in **Node location by mouse click** group to activate specifying location of a new node. You can specify it
+
+ * by clicking with your mouse on the face in the Viewer,
+ * by typing coordinates in **X, Y, Z** fields,
+ * by setting coordinates using arrows of spin boxes.
+
+#. Activate **Preview** to see a result of the operation.
+
+#. Click the **Apply** or **Apply and Close** button to confirm the operation.
+
+**See Also** a sample TUI Script of a :ref:`tui_cutting_triangles` operation.