3 \page a1d_meshing_hypo_page 1D Meshing Hypotheses
7 <li>\ref arithmetic_1d_anchor "Arithmetic 1D"</li>
8 <li>\ref average_length_anchor "Average Length"</li>
9 <li>\ref max_length_anchor "Max Size"</li>
10 <li>\ref deflection_1d_anchor "Deflection 1D"</li>
11 <li>\ref number_of_segments_anchor "Number of segments"</li>
12 <li>\ref start_and_end_length_anchor "Start and end length"</li>
13 <li>\ref automatic_length_anchor "Automatic Length"</li>
14 <li>\ref fixed_points_1d_anchor "Fixed points 1D"</li>
18 \anchor arithmetic_1d_anchor
19 <h2>Arithmetic 1D hypothesis</h2>
21 <b>Arithmetic 1D</b> hypothesis allows to split edges into segments with a
22 length that changes in arithmetic progression (Lk = Lk-1 + d)
23 beginning from a given starting length and up to a given end length.
25 The direction of the splitting is defined by the orientation of the underlying geometrical edge.
26 <b>"Reverse Edges"</b> list box allows to specify the edges for which the splitting should be made
27 in the direction opposing to their orientation. This list box is enabled only if the geometry object
28 is selected for the meshing. In this case the user can select edges to be reversed either directly
29 picking them in the 3D viewer or by selecting the edges or groups of edges in the Object browser.
31 \image html a-arithmetic1d.png
33 \image html b-ithmetic1d.png "Arithmetic 1D hypothesis - the size of mesh elements gradually increases"
35 <b>See Also</b> a sample TUI Script of a
36 \ref tui_1d_arithmetic "Defining Arithmetic 1D hypothesis" operation.
39 \anchor deflection_1d_anchor
40 <h2>Deflection 1D hypothesis</h2>
42 <b>Deflection 1D</b> hypothesis can be applied for meshing curvilinear edges
43 composing your geometrical object. It uses only one parameter: the
45 \n A geometrical edge is divided into equal segments. The maximum
46 distance between a point on the edge within a segment and the line
47 connecting the ends of the segment should not exceed the specified
48 value of deflection . Then mesh nodes are constructed at end segment
49 locations and 1D mesh elements are constructed on segments.
51 \image html a-deflection1d.png
53 \image html b-flection1d.png "Deflection 1D hypothesis - useful for meshing curvilinear edges"
55 <b>See Also</b> a sample TUI Script of a
56 \ref tui_deflection_1d "Defining Deflection 1D hypothesis" operation.
59 \anchor average_length_anchor
60 <h2>Average Length hypothesis</h2>
62 <b>Average Length</b> hypothesis can be applied for meshing of edges
63 composing your geometrical object. Definition of this hypothesis
64 consists of setting the \b length of segments, which will split these
65 edges, and the \b precision of rounding. The points on the edges
66 generated by these segments will represent nodes of your mesh.
67 Later these nodes will be used for meshing of the faces abutting to
70 The \b precision parameter is used to allow rounding a number of
71 segments, calculated from the edge length and average length of
72 segment, to the lower integer, if this value outstands from it in
73 bounds of the precision. Otherwise, the number of segments is rounded
74 to the higher integer. Use value 0.5 to provide rounding to the
75 nearest integer, 1.0 for the lower integer, 0.0 for the higher
76 integer. Default value is 1e-07.
78 \image html image41.gif
80 \image html a-averagelength.png
82 \image html b-erage_length.png "Average length hypothesis - all 1D mesh elements are roughly equal"
84 <b>See Also</b> a sample TUI Script of a
85 \ref tui_average_length "Defining Average Length" hypothesis
88 <br>\anchor max_length_anchor
90 <b>Max Size</b> hypothesis allows splitting geometrical edges into
91 segments not longer than the given length. Definition of this hypothesis
92 consists of setting the maximal allowed \b length of segments.
93 <b>Use preestimated length</b> check box lets you specify \b length
94 automatically calculated basing on size of your geometrical object,
95 namely as diagonal of bounding box divided by ten. The divider can be
96 changed via "Ratio Bounding Box Diagonal / Max Size"
98 <b>Use preestimated length</b> check box is enabled only if the
99 geometrical object has been selected before hypothesis definition.
101 \image html a-maxsize1d.png
104 \anchor number_of_segments_anchor
105 <h2>Number of segments hypothesis</h2>
107 <b>Number of segments</b> hypothesis can be applied for meshing of edges
108 composing your geometrical object. Definition of this hypothesis
109 consists of setting the number of segments, which will split these
110 edges. In other words your edges will be split into a definite number
111 of segments with approximately the same length. The points on the
112 edges generated by these segments will represent nodes of your
113 mesh. Later these nodes will be used for meshing of the faces abutting
116 The direction of the splitting is defined by the orientation of the underlying geometrical edge.
117 <b>"Reverse Edges"</b> list box allows to specify the edges for which the splitting should be made
118 in the direction opposing to their orientation. This list box is enabled only if the geometry object
119 is selected for the meshing. In this case the user can select edges to be reversed either directly
120 picking them in the 3D viewer or by selecting the edges or groups of edges in the Object browser.
122 \image html image46.gif
124 You can set the type of distribution for this hypothesis in the
125 <b>Hypothesis Construction</b> dialog bog :
127 \image html a-nbsegments1.png
129 <br><b>Equidistant Distribution</b> - all segments will have the same
130 length, you define only the <b>Number of Segments</b>.
132 <br><b>Scale Distribution</b> - length of segments gradually changes depending on the <b>Scale Factor</b>, which is a ratio of the first segment length to the last segment length.
134 \image html a-nbsegments2.png
136 <br><b>Distribution with Table Density</b> - you input a number of
137 pairs <b>t - F(t)</b>, where \b t ranges from 0 to 1, and the module computes the
138 formula, which will rule the change of length of segments and shows
139 the curve in the plot. You can select the <b>Conversion mode</b> from
140 \b Exponent and <b>Cut negative</b>.
142 \image html distributionwithtabledensity.png
144 <br><b>Distribution with Analytic Density</b> - you input the formula,
145 which will rule the change of length of segments and the module shows
146 the curve in the plot.
148 \image html distributionwithanalyticdensity.png
150 <b>See Also</b> a sample TUI Script of a
151 \ref tui_deflection_1d "Defining Number of Segments" hypothesis
155 \anchor start_and_end_length_anchor
156 <h2>Start and End Length hypothesis</h2>
158 <b>Start and End Length</b> hypothesis allows to divide a geometrical edge
159 into segments so that the first and the last segments have a specified
160 length. The length medium segments changes with automatically chosen
161 geometric progression. Then mesh nodes are
162 constructed at segment ends location and 1D mesh elements are
165 The direction of the splitting is defined by the orientation of the underlying geometrical edge.
166 <b>"Reverse Edges"</b> list box allows to specify the edges for which the splitting should be made
167 in the direction opposing to their orientation. This list box is enabled only if the geometry object
168 is selected for the meshing. In this case the user can select edges to be reversed either directly
169 picking them in the 3D viewer or by selecting the edges or groups of edges in the Object browser.
171 \image html a-startendlength.png
173 \image html b-art_end_length.png "The lengths of the first and the last segment are strictly defined"
175 <b>See Also</b> a sample TUI Script of a
176 \ref tui_start_and_end_length "Defining Start and End Length"
177 hypothesis operation.
180 \anchor automatic_length_anchor
181 <h2>Automatic Length</h2>
183 This hypothesis is automatically applied when you select <b>Assign a
184 set of hypotheses</b> option in Create Mesh menu.
186 \image html automaticlength.png
188 The dialog box prompts you to define the quality of the future mesh by
189 only one parameter, which is \b Fineness, ranging from 0 (coarse mesh,
190 low number of elements) to 1 (extremely fine mesh, great number of
191 elements). Compare one and the same object (sphere) meshed with
192 minimum and maximum value of this parameter.
194 \image html image147.gif "Example of a very rough mesh. Automatic Length works for 0."
196 \image html image148.gif "Example of a very fine mesh. Automatic Length works for 1."
199 \anchor fixed_points_1d_anchor
200 <h2>Fixed points 1D hypothesis</h2>
202 <b>Fixed points 1D</b> hypothesis allows splitting edges through a
203 set of points parameterized on the edge (from 1 to 0) and a number of segments for each
204 interval limited by the points.
206 \image html hypo_fixedpnt_dlg.png
208 It is possible to check in <b>Same Nb. Segments for all intervals</b>
209 option and to define one value for all intervals.
211 The splitting direction is defined by the orientation of the
212 underlying geometrical edge. <b>"Reverse Edges"</b> list box allows to
213 specify the edges for which the splitting should be made in the
214 direction opposite to their orientation. This list box is enabled only
215 if the geometrical object is selected for meshing. In this case it is
216 possible to select the edges to be reversed either directly picking them in
217 the 3D viewer or selecting the edges or groups of edges in the
220 \image html mesh_fixedpnt.png "Example of a submesh on the edge built using Fixed points 1D hypothesis"
222 <b>See Also</b> a sample TUI Script of a
223 \ref tui_fixed_points "Defining Fixed Points" hypothesis operation.