X-Git-Url: http://git.salome-platform.org/gitweb/?a=blobdiff_plain;f=doc%2Fsalome%2Fgui%2FSMESH%2Finput%2Fprism_3d_algo.doc;h=d377b549fba48f3514c584d8c461a661ece47d78;hb=88068fce89e10cb32b60ea51cae3440240d42e9f;hp=5589ba3a761c8199ea4716deab69ce9cacb9ad88;hpb=bd4e115a78b52e3fbc016e5e30bb0e19b2a9e7d6;p=modules%2Fsmesh.git diff --git a/doc/salome/gui/SMESH/input/prism_3d_algo.doc b/doc/salome/gui/SMESH/input/prism_3d_algo.doc index 5589ba3a7..d377b549f 100644 --- a/doc/salome/gui/SMESH/input/prism_3d_algo.doc +++ b/doc/salome/gui/SMESH/input/prism_3d_algo.doc @@ -2,23 +2,70 @@ \page prism_3d_algo_page 3D extrusion meshing algorithm -3D extrusion algorithm can be used for meshing prisms, i.e. 3D Shapes +3D extrusion algorithm can be used for meshing prisms, i.e. 3D shapes defined by two opposing faces having the same number of vertices and -edges and meshed using, for example, the \ref projection_algos_page -"2D Projection" algorithm. These two faces should be connected by -quadrangle "side" faces. +edges. These two faces should be connected by quadrangle "side" faces. -The opposing faces can be meshed with either quadrangles or triangles, -while the side faces should be meshed with quadrangles only. +The prism is allowed to have sides composed of several faces. (A prism +side is a row of faces (or one face) connecting the corresponding edges of +the top and base faces). However, a prism +side can be split only vertically as indicated in the +picture below. -\image html image157.gif "Prism with 3D extrusion meshing". +\image html prism_ok_ko.png "A suitable and an unsuitable prism" +In this picture, the left prism is suitable for meshing with 3D +extrusion algorithm: it has six sides, two of which are split +vertically. The right prism cannot be meshed with this +algorithm because one of the prism sides is split horizontally (the +splitting edge is highlighted). -As you can see, the 3D extrusion algorithm permits to build and to -have in the same 3D mesh such elements as hexahedrons, prisms and -polyhedrons. +The algorithm can propagate 2D mesh not only between horizontal +(i.e. base and top) faces of one prism but also between faces of prisms +organized in a stack and between stacks sharing prism sides. -\note This algorithm works correctly only if the opposing faces have -the same (or similar) meshing topography. Otherwise, 3D extrusion -algorithm can fail to build mesh volumes. +\image html prism_stack.png "Prism stacks" +This picture shows four neighboring prism stacks, each comprising two prisms. +The shown sub-mesh is used by the algorithm to mesh +all eight prisms in the stacks. + +To use 3D extrusion algorithm you need to assign algorithms +and hypotheses of lower dimensions as follows. +(A sample picture below shows algorithms and hypotheses used to +mesh a cylinder with prismatic volumes). + +\image html prism_needs_hyps.png + +The \b Global algorithms and hypotheses to be chosen at +\ref create_mesh_anchor "Creation of a mesh object" are: + + +The \b Local algorithms and hypotheses to be chosen at +\ref constructing_submeshes_page "Construction of sub-meshes" are: + + +\image html image157.gif "Prism with 3D extrusion meshing. Vertical division is different on neighbor edges because several local 1D hypotheses are assigned." + +\sa a sample TUI Script of +\ref tui_prism_3d_algo "Use 3D extrusion meshing algorithm". */