<ul>
<li>\ref max_element_area_anchor "Max Element Area"</li>
<li>\ref length_from_edges_anchor "Length from Edges"</li>
-<li>\ref quadrangle_preference_anchor "Quadrangle Preference"</li>
+<li>\ref hypo_quad_params_anchor "Quadrangle parameters"</li>
</ul>
<br>
\image html a-maxelarea.png
-\image html max_el_area.png
+\n
+
+\image html max_el_area.png "In this example, Max. element area is very small compared to the 1D hypothesis"
<b>See Also</b> a sample TUI Script of a
\ref tui_max_element_area "Maximum Element Area" hypothesis
\ref tui_length_from_edges "Length from Edges" hypothesis operation.
<br>
-\anchor quadrangle_preference_anchor
-<h2>Quadrangle Preference</h2>
+\anchor hypo_quad_params_anchor
+<h2>Quadrangle parameters</h2>
+
+<b>Quadrangle parameters</b> is a hypothesis for
+Quadrangle (Mapping), which allows using this algorithm for meshing of
+triangular faces.In this case it is necessary to select the <b>Base vertex</b>
+used as a degenerated edge.
+
+\image html hypo_quad_params_1.png "A face built from 3 edges"
+
+\image html hypo_quad_params_res.png "The resulting mesh"
+
+This hypothesis can be also used to mesh a segment of a circular face.
+Please, consider that there is a limitation on the selectiion of the degenerated
+vertex for the faces built with the angle > 180 degrees (see the picture).
+
+\image html hypo_quad_params_2.png "3/4 of a circular face"
+
+In this case, selection of a wrong vertex for the <b>Quadrangle parameters</b>
+hypothesis will generate a wrong mesh. The picture below
+shows the good (left) and the bad (right) results of meshing.
+
+\image html hypo_quad_params_res_2.png "The resulting meshes"
+
+<b>See Also</b> a sample TUI Script of a
+\ref tui_quadrangle_parameters "Quadrangle Parameters" hypothesis.
-This algorithm can be used only together with Quadrangle (Mapping)
-algorithm. It allows to build quadrangular meshes even if the number
-of nodes at the opposite edges of a meshed face is not equal,
-otherwise this mesh will contain some triangular elements.
<br>
-This hypothesis has one restriction on its work: the total quantity of
-segments on all four sides of the face must be even (divisible by 2).
*/
