X-Git-Url: http://git.salome-platform.org/gitweb/?a=blobdiff_plain;f=doc%2Fsalome%2Fgui%2FSMESH%2Finput%2F1d_meshing_hypo.doc;fp=doc%2Fsalome%2Fgui%2FSMESH%2Finput%2F1d_meshing_hypo.doc;h=0000000000000000000000000000000000000000;hb=f0f67c0b47e58361bc50c7169734da604fbfca01;hp=c4de6317c9d1dd4d24a0d115ad88d69ebb060b61;hpb=f6825d843153c333e95e1345ef7c7fc2d0fe5698;p=modules%2Fsmesh.git diff --git a/doc/salome/gui/SMESH/input/1d_meshing_hypo.doc b/doc/salome/gui/SMESH/input/1d_meshing_hypo.doc deleted file mode 100644 index c4de6317c..000000000 --- a/doc/salome/gui/SMESH/input/1d_meshing_hypo.doc +++ /dev/null @@ -1,370 +0,0 @@ -/*! - -\page a1d_meshing_hypo_page 1D Meshing Hypotheses - -Basic 1D hypothesis specifies: - - -1D hypotheses can be categorized by type of nodes distribution as follows: - - -
-\anchor adaptive_1d_anchor -

Adaptive hypothesis

- -Adaptive hypothesis allows to split edges into segments with a -length that depends on the curvature of edges and faces and is limited by Min. Size -and Max Size. The length of a segment also depends on the lengths -of adjacent segments (that can't differ more than twice) and on the -distance to close geometrical entities (edges and faces) to avoid -creation of narrow 2D elements. - -\image html adaptive1d.png - -- Min size parameter limits the minimal segment size. -- Max size parameter defines the length of segments on straight edges. -- \b Deflection parameter gives maximal distance of a segment from a curved edge. - -\image html adaptive1d_sample_mesh.png "Adaptive hypothesis and NETGEN 2D algorithm - the size of mesh segments reflects the size of geometrical features" - -See Also a \ref tui_1d_adaptive "sample TUI Script" that uses Adaptive hypothesis. - -
-\anchor arithmetic_1d_anchor -

Arithmetic Progression hypothesis

- -Arithmetic Progression hypothesis allows to split edges into segments with a -length that changes in arithmetic progression (Lk = Lk-1 + d) -beginning from a given starting length and up to a given end length. - -The splitting direction is defined by the orientation of the -underlying geometrical edge. -Reverse Edges list box allows specifying the edges, for which -the splitting should be made in the direction opposite to their -orientation. This list box is usable only if a geometry object is -selected for meshing. In this case it is possible to select edges to -be reversed either directly picking them in the 3D viewer or by -selecting the edges or groups of edges in the Object Browser. Use \b -Add button to add the selected edges to the list. - -\ref reversed_edges_helper_anchor "Helper" group assists you in -defining Reversed Edges parameter. - - -\image html a-arithmetic1d.png - -\image html b-ithmetic1d.png "Arithmetic Progression hypothesis - the size of mesh elements gradually increases" - -See Also a sample TUI Script of a -\ref tui_1d_arithmetic "Defining Arithmetic Progression and Geometric Progression hypothesis" operation. - -
-\anchor geometric_1d_anchor -

Geometric Progression hypothesis

- -Geometric Progression hypothesis allows splitting edges into -segments with a length that changes in geometric progression (Lk = -Lk-1 * d) starting from a given Start Length and with a given -Common Ratio. - -The splitting direction is defined by the orientation of the -underlying geometrical edge. -Reverse Edges list box allows specifying the edges, for which -the splitting should be made in the direction opposite to their -orientation. This list box is usable only if a geometry object is -selected for meshing. In this case it is possible to select edges to -be reversed either directly picking them in the 3D viewer or by -selecting the edges or groups of edges in the Object Browser. Use \b -Add button to add the selected edges to the list. - -\ref reversed_edges_helper_anchor "Helper" group assists you in -defining Reversed Edges parameter. - -\image html a-geometric1d.png - -See Also a sample TUI Script of a -\ref tui_1d_arithmetic "Defining Arithmetic Progression and Geometric Progression hypothesis" operation. - -
-\anchor deflection_1d_anchor -

Deflection hypothesis

- -Deflection hypothesis can be applied for meshing curvilinear edges -composing your geometrical object. It defines only one parameter: the -value of deflection (or chord error). - -A geometrical edge is divided into segments of length depending on -edge curvature. The more curved the edge, the shorter the -segment. Nodes on the edge are placed so that the maximum distance -between the edge and a segment approximating a part of edge between -two nodes should not exceed the value of deflection. - -\image html a-deflection1d.png - -\image html b-flection1d.png "Deflection hypothesis - useful for meshing curvilinear edges" - -See Also a sample TUI Script of a -\ref tui_deflection_1d "Defining Deflection hypothesis" operation. - -
-\anchor average_length_anchor -

Local Length hypothesis

- -Local Length hypothesis can be applied for meshing of edges -composing your geometrical object. Definition of this hypothesis -consists of setting the \b length of segments, which will approximate these -edges, and the \b precision of rounding. - -The \b precision parameter is used to round a number of segments, -calculated by dividing the edge length by the specified \b length of -segment, to the higher integer if the \a remainder exceeds the \b precision -and to the lower integer otherwise.
-Use value 0.5 to provide rounding to the nearest integer, 1.0 for the lower integer, 0.0 for the higher integer. Default value is 1e-07. - -For example: if edge length is 10.0 and the segment \b length -is 3.0 then their division gives 10./3. = 3.33(3) and the \a remainder is 0.33(3). -If \b precision is less than 0.33(3) then the edge is divided into 3 segments. -If \b precision is more than 0.33(3) then the edge is divided into 4 segments. - - -\image html image41.gif - -\image html a-averagelength.png - -\image html b-erage_length.png "Local Length hypothesis - all 1D mesh segments are equal" - -See Also a sample TUI Script of a -\ref tui_average_length "Defining Local Length" hypothesis -operation. - -
\anchor max_length_anchor -

Max Size

-Max Size hypothesis allows splitting geometrical edges into -segments not longer than the given length. Definition of this hypothesis -consists of setting the maximal allowed \b length of segments. -Use preestimated length check box lets you use \b length -automatically calculated basing on size of your geometrical object, -namely as diagonal of bounding box divided by ten. The divider can be -changed via \ref diagonal_size_ratio_pref "Ratio Bounding Box Diagonal / Max Size" -preference parameter. -Use preestimated length check box is enabled only if the -geometrical object has been selected before hypothesis definition. - -\image html a-maxsize1d.png - -
-\anchor number_of_segments_anchor -

Number of Segments hypothesis

- -Number of Segments hypothesis can be applied for approximating -edges by a definite number of mesh segments with length depending on -the selected type of distribution of nodes. The default number of -segments can be set via -\ref nb_segments_pref "Automatic Parameters / Default Number of Segments" -preference parameter. - -The direction of the splitting is defined by the orientation of the -underlying geometrical edge. Reverse Edges list box allows to -specify the edges for which the splitting should be made in the -direction opposing to their orientation. This list box is enabled only -if the geometry object is selected for the meshing. In this case it is -possible to select edges to be reversed either by directly picking them -in the 3D viewer or by selecting the edges or groups of edges in the -Object Browser. - -\ref reversed_edges_helper_anchor "Helper" group assists you in -defining Reversed Edges parameter. - -You can set the type of node distribution for this hypothesis in the -Hypothesis Construction dialog bog : - -\image html a-nbsegments1.png - -
Equidistant Distribution - all segments will have the same -length, you define only the Number of Segments. - -
Scale Distribution - length of segments gradually changes -depending on the Scale Factor, which is a ratio of the first -segment length to the last segment length.
-Length of segments changes in geometric progression with the common -ratio (A) depending on the Scale Factor (S) and Number of -Segments (N) as follows: A = S**(1/(N-1)). For an -edge of length L, length of the first segment is -L * (1 - A)/(1 - A**N). - - -\image html a-nbsegments2.png - -
Distribution with Analytic Density - you input the formula, -which will rule the change of length of segments and the module shows -in the plot the density function curve in red and the node -distribution as blue crosses. - -\image html distributionwithanalyticdensity.png - -
-\anchor analyticdensity_anchor -The node distribution is computed so that to have the density function -integral on the range between two nodes equal for all segments. -\image html analyticdensity.png - -
Distribution with Table Density - you input a number of -pairs t - F(t), where \b t ranges from 0 to 1, and the module computes the -formula, which will rule the change of length of segments and shows -in the plot the density function curve in red and the node -distribution as blue crosses. The node distribution is computed in the -same way as for -\ref analyticdensity_anchor "Distribution with Analytic Density". You -can select the Conversion mode from \b Exponent and Cut -negative. - -\image html distributionwithtabledensity.png - -See Also a sample TUI Script of a -\ref tui_deflection_1d "Defining Number of Segments" hypothesis -operation. - -\note The plot functionality is available only if GUI module is built with Plot 2D Viewer (option SALOME_USE_PLOT2DVIEWER is ON when building GUI module). - -
-\anchor start_and_end_length_anchor -

Start and End Length hypothesis

- -Start and End Length hypothesis allows to divide a geometrical edge -into segments so that the first and the last segments have a specified -length. The length of medium segments changes with automatically chosen -geometric progression. - -The direction of the splitting is defined by the orientation of the -underlying geometrical edge. Reverse Edges list box allows to -specify the edges, for which the splitting should be made in the -direction opposing to their orientation. This list box is enabled only -if the geometry object is selected for the meshing. In this case it is -possible to select edges to be reversed either by directly picking them -in the 3D viewer or by selecting the edges or groups of edges in the -Object Browser. - -\ref reversed_edges_helper_anchor "Helper" group assists you in -defining Reversed Edges parameter. - - -\image html a-startendlength.png - -\image html b-art_end_length.png "The lengths of the first and the last segment are strictly defined" - -See Also a sample TUI Script of a -\ref tui_start_and_end_length "Defining Start and End Length" -hypothesis operation. - -
-\anchor automatic_length_anchor -

Automatic Length

- -The dialog box prompts you to define the quality of the future mesh by -only one parameter, which is \b Fineness, ranging from 0 (coarse mesh, -low number of segments) to 1 (extremely fine mesh, great number of -segments). - -\image html automaticlength.png - -Compare one and the same object (sphere) meshed with -minimum and maximum value of this parameter. - -\image html image147.gif "Example of a rough mesh at Automatic Length Fineness of 0." - -\image html image148.gif "Example of a fine mesh at Automatic Length Fineness of 1." - -
-\anchor fixed_points_1d_anchor -

Fixed Points hypothesis

- -Fixed Points hypothesis allows splitting edges through a -set of points parametrized on the edge (from 1 to 0) and a number of -segments for each interval limited by the points. - -\image html hypo_fixedpnt_dlg.png - -It is possible to check in Same Nb. Segments for all intervals -option and to define one value for all intervals. - -The splitting direction is defined by the orientation of the -underlying geometrical edge. Reverse Edges list box allows to -specify the edges for which the splitting should be made in the -direction opposite to their orientation. This list box is enabled only -if the geometrical object is selected for meshing. In this case it is -possible to select the edges to be reversed either directly picking them in -the 3D viewer or selecting the edges or groups of edges in the -Object Browser. - -\ref reversed_edges_helper_anchor "Helper" group assists in -defining Reversed Edges parameter. - - -\image html mesh_fixedpnt.png "Example of a sub-mesh on the edge built using Fixed Points hypothesis" - -See Also a sample TUI Script of a -\ref tui_fixed_points "Defining Fixed Points" hypothesis operation. - -\anchor reversed_edges_helper_anchor -

Reversed Edges Helper

- -\image html rev_edges_helper_dlg.png - -\b Helper group assists in defining Reversed Edges -parameter of the hypotheses depending on edge direction. - -Show whole geometry check-box allows seeing the whole -geometrical model in the 3D Viewer, which can help to understand the -location of a set of edges within the model. - -Propagation chains group allows defining Reversed Edges -for splitting opposite edges of quadrilateral faces in a logically -uniform direction. When this group is activated, the list is filled -with propagation chains found within the shape on which a hypothesis -is assigned. When a chain is selected in the list its edges are shown -in the Viewer with arrows, which enables choosing a common direction -for all chain edges. \b Reverse button inverts the common direction of -chain edges. \b Add button is active if some edges of a chain have a -different direction, so you can click \b Add button to add them -to Reversed Edges list. - -\image html propagation_chain.png "The whole geometry and a propagation chain" - -\note Alternatively, uniform direction of edges of one propagation -chain can be achieved by -\ref constructing_submeshes_page "definition of a sub-mesh" on one -edge of the chain and assigning a -\ref propagation_anchor "Propagation" additional hypothesis. -Orientation of this edge (and hence of all the rest edges of the chain) can be -controlled by using Reversed Edges field. - -*/