YamsPlugDialog 0 0 800 500 MGSurfOpt : Remeshing tool false Qt::Horizontal QSizePolicy::Minimum 10 20 Compute Close Qt::Horizontal 30 20 Save 18 18 Load 18 18 Default Qt::Horizontal 30 20 10 Help Qt::Horizontal QSizePolicy::Minimum 10 20 10 0 Simple Remeshing Options 10 140 750 270 Optimisation Qt::Horizontal QSizePolicy::Minimum 30 20 Quality improvement is done by point smoothing and edge swapping. Quality improvement Only true The given surface triangulation is enriched (no coarsening at all) in such away that the distance between the elements in the final mesh and those of the initial one is bounded by auser specified tolerance value. One should use this option, to enrich the mesh where purely geometrical features may be insuficiently fine, i.e. the resulting mesh will be least as fine as the input. Mesh and the geometric features will be refined if needed as specified by the other program parameters. The meshes obtained with those settings may not be suitable for computation. Pure Geometry Enrichment false An uniform subdivision of the given surface triangulation is performed : each triangle of the given surface triangulation is considered at and is divided into identical triangles. Uniform Subdivision false A surface sandpapering without shrinkage of the given surface triangulation is performed, i.e., the high curvature variations of the given surface will be smoothed out without shrinking the volume in doing so. If ridges are defined, they will be kept as they are in the resulting mesh. This option modifies the geometry. Sandpapering false The given surface triangulation is modified in such a way that the distance between the elements in the final mesh and those of the initial one is bounded by a user specfied tolerance value. One should use this option, to coarsen when a purely geometrical mesh is needed. (a mesh that keeps and obeys its geometric features only.) The meshes obtained with this option are usually not suitable for computation because anisotropic elements may be generated Geometrical Mesh : Coarsening The given surface triangulation is modified in such a way that the distance between the elements in the final mesh and those of the initial one is bounded by a user specfied tolerance value. One should use this option, to coarsen and enrich when a purely geometrical mesh is needed. (a mesh that keeps and obeys its geometric features only.) The meshes obtained with this setting are usually not suitable for computation because anisotropic elements may be generated Geometrical Mesh : Coarsening and Enrichment The given surface triangulation is modified in accordance to a size map. The latter can be either the intrinsic size map (computed automatically and based on the surface properties, i.e. the local curvatures), or on a given size map (which is then combined to the intrinsic size map). One should use this option to coarsen the mesh, when a regular mesh for computation purposes is desired, i.e. a mesh with good aspect ratios or good quality elements. Mesh for finite element computation : Coarsening The given surface triangulation is modified in accordance to a size map. The latter can be either the intrinsic size map (computed automatically and based on the surface properties, i.e. the local curvatures), or on a given size map (which is then combined to the intrinsic size map). One should use this option to coarse and enrich the mesh, when a regular mesh for computation purposes is desired, i.e. a mesh with good aspect ratios or good quality elements Mesh for finite element computation : Coarsening and Enrichment 10 420 750 70 This parameter enables the user to bound the maximal chordal deviation allowed, that is the maximal distance allowed between the detected curve and the plane P of the corresponding mesh face. In other words, it avoids having faces too far away from the curve they should represent. Chordal deviation Tolerance 40 30 110 24 If the Units parameter is relative, epsilon max correspond to (per thousand) s*Tolerance/1000, where s is the size of the bounding box of the domain. If the Units parameter is absolute, the tolerance parameter is expressed in model units: if P=2 and point coordinates are given in millimeters, the maximal chordal deviation is 2 mm. 220 30 120 24 Values are expressed in the model units. Absolute units false 350 30 120 24 Values are relative (per thousand) to the bounding box size. Relative units true 10 10 750 120 10 Original Mesh 40 70 190 31 10 Mesh File GMF format 18 18 240 70 481 31 10 40 30 190 31 Mesh Object Browser 18 18 false 240 30 481 31 10 10 80 31 18 or GBUnit groupBox GBOptim Advanced Remeshing Options 10 10 750 120 You can set/unset 30 20 271 25 If not set (ridge detection disabled), Yams will not try to detect any new ridge edge by its own mechanism : it will consider as ridge only the ridges given in the mesh. All non-ridge edges that would have been detected as ridge by the ridge angle parameter (see below) will be considered as part of the same continuous patch. This option should not be checked when all the known ridges of the mesh are given and when all other possible ridges are not geometric ridges to take into account. ridge detection true 30 50 271 25 When not set (point smoothing is disabled), Yams will not try to move the initial given vertices (along an edge, a ridge or onto the surface), hence Yams will only swap edges, remove vertices or add vertices (refines) to change the mesh. point smoothing true 30 80 271 25 If set, Yams creates new vertices placed on the curved surface and adds them to elements. It means one extra vertex on edge (P2 or quadratic triangles). New created vertices are saved in the .mesh file under keyword section 'Vertices' split edge false 10 140 750 270 You can control 30 30 100 25 0.890000000000000 0.010000000000000 0.040000000000000 140 30 630 30 This field (as well as tolerance) enables the user to control the accuracy of the piecewise linear approximation of the surface. This parameter enables the user to control the maximal angle allowed between two adjacent faces. It can be used to bound the maximal deviation of the mesh faces from the tangent planes at mesh vertices. In other words, it avoids having sharp angles between faces representing a smooth curve. This parameter enables the user to specify the maximal chordal deviation "max relatively to the curvature. Following that criterion: - if the chordal deviation epsilon is smaller than epsilon max*r, it is acceptable to remove the considered point; - if the chordal deviation epsilon is greater than epsiolon max*r, the considered mesh face should be redefined by adding a point on the curve. One can see that the smaller the radius r, the harder it is to satisfy this criterion: epsilon max is a real value corresponding to a percentage, the ratio between the chordal deviation to the local curvature. This field is used only for optimisation style -O values of -1, 0 and 1. The default value for "max is set to 0:04 which leads to angles of less than 33 degrees between two adjacent faces. Geometrical approximation: Maximum angle allowed between a face and a curve (not separated by a ridge). 30 70 100 25 90.000000000000000 45.000000000000000 140 70 630 30 If the angle between the normal vectors of two adjacent faces exceeds this value, the edge common to the faces is a ridge. 30 110 100 25 0.010000000000000 100.000000000000000 0.100000000000000 100.000000000000000 140 110 630 30 This parameter allows the user to prescribe a maximal size hmax for the mesh elements i.e., the lengths of the edges with respect to the specified size map. The corresponding values are either relative or absolute depending on the choosen parameter. The default values are automatically set based on the surface geometry (curvature dependent) and its bounding box size. Please note that, as it is not strictly possible to obey the given or computed size map, the actual maximal size may be slightly bigger than the prescribed ones. Maximal size allowed around vertices, the lengths of the edges with respect to the specified size map. 30 150 100 25 0.000000000000000 100.000000000000000 0.100000000000000 5.000000000000000 140 150 630 30 This parameter allows the user to prescribe a maximal size hmax for the mesh elements i.e., the lengths of the edges with respect to the specified size map. The corresponding values are either relative or absolute depending on the choosen parameter. The default values are automatically set based on the surface geometry (curvature dependent) and its bounding box size. Please note that, as it is not strictly possible to obey the given or computed size map, the actual maximal size may be slightly bigger than the prescribed ones. Minimal size allowed around vertices, the lengths of the edges with respect to the specified size map. 30 190 100 25 0.010000000000000 1.300000000000000 140 190 630 30 This parameter enables the user to control the element size variation in the triangulation. Yams will avoid getting two adjacent edges which sizes differ by a factor bigger than this parameter. To avoid rapid size variations, a size correction procedure is applied to the size map. In other words: if two adjacent edges are respectively e1 and e2 long if e2 > parameter * e1 then e02 the new size for the second edge will be set to parameter* e1. This procedure is de-activated if yams computes a mesh for finite element with only coarsening. The default value is 1.3, which is the usual value set for computational meshes. Mesh Gradation: the element size variation in the triangulation. Yams will avoid having two adjacent edges which sizes vary more than the given gradation. Generic Options 10 10 750 130 Yams Generic Options 20 30 100 25 10 3 130 30 600 30 sets the verbosity level. From 0 (no detail) to 10 (very detailed). Default is 3. Verbosity level 20 70 100 25 100000 0 130 70 600 30 The program requires roughly about 370 bytes per point. It is thus possible to estimate a priori the required memory size to complete a job. As an example of memory space needed, a mesh of 543,652 points (1,087,716 triangles) requires 182 Mbytes (about 351 bytes per point). Conversely, a workstation having 512 Mbytes of memory can handle a mesh of about 2,750,000 points. The memory needed for mesh modification is allocated dynamically at the beginning of the procedure (data reading), based on the initial triangulation size. When the program reaches the amount of maximal memory allowed, it will stop inserting points and, if possible, the current mesh will be saved as it is, valid and conformal, provided the input mesh was valid and conformal. Specify the memory if: - the automatically allocated memory reveals insufficient when the user asked to enrich the given mesh. - you want to limit the amount of memory used by the program. If the input mesh size requires more memory than requested or if the allocated memory (user defined or not) exceeds the machine capabilities, the tool will stop because of insufficient memory. Memory size (in Mbytes) 10 150 750 170 Plug-in Generic Options 20 40 391 18 File used to save Yams hypothesis parameters : 20 70 30 31 60 70 661 31 20 110 70 31 Save 18 18 120 110 70 31 Load 18 18