example.jig

#
#   EXAMPLE.JIG: an example config. file for JIGSAW
#

#   To run this example navigate to the directory containing 
#   this file and run the following from the cmd line:
#
#   On WIN platforms:
#
#       bin\jigsaw.exe example.jig
#
#   On LNX platforms:
#
#       bin/jigsaw     example.jig
#
#   This command calls JIGSAW using the config. data contai-
#   ned in "example.jig", which, in unmodified form, creates 
#   a tetrahedral mesh of the "stanford-bunny" geometry. 
#

#   The subsequent sections detail the various configuration 
#   options available for JIGSAW. Simply uncomment any given 
#   option and re-run JIGSAW to explore its effect.
# 

#
#   REQUIRED fields:
#   ---------------
#

#   ---> GEOM_FILE - 'GEOMNAME.MSH', a string containing the 
#       name of the geometry file (is required at input). 
#

    GEOM_FILE = geo/bunny.msh
    
    
#   ---> MESH_FILE - 'MESHNAME.MSH', a string containing the 
#       name of the output file (will be created on output).
#

    MESH_FILE = out/bunny.msh


#    
#   OPTIONAL fields (INIT):
#   ----------------------
#

#   ---> INIT_FILE - 'INITNAME.MSH', a string containing the 
#       name of the initial distribution file (is required 
#       at input).
#

#   INIT_FILE = *.msh


#   ---> INIT_NEAR - {default = 1.E-8} relative "zip" tol.
#       applied when processing initial conditions. In cases
#       where "sharp-feature" detection is active, nodes in 
#       the initial set are zipped to their nearest feature
#       node if the separation length is less than NEAR*SCAL
#       where SCAL is the max. bounding-box dimension.
#

#   INIT_NEAR = 1.E-6


#
#   OPTIONAL fields (GEOM):
#   ----------------------
#

#   ---> GEOM_SEED - {default=8} number of "seed" vertices 
#       used to initialise mesh generation.
#

#   GEOM_SEED = 16


#   ---> GEOM_FEAT - {default=false} attempt to auto-detect 
#       "sharp-features" in the input geometry. Features can 
#       lie adjacent to 1-dim. entities, (i.e. geometry 
#       "edges") and/or 2-dim. entities, (i.e. geometry 
#       "faces") based on both geometrical and/or topologic-
#       al constraints. Geometrically, features are located 
#       between any neighbouring entities that subtend 
#       angles less than GEOM_ETAX degrees, where "X" is the 
#       (topological) dimension of the feature. Topological-
#       ly, features are located at the apex of any non-man-
#       ifold connections.
#

#   GEOM_FEAT = TRUE


#   ---> GEOM_ETA1 - {default=45deg} 1-dim. feature-angle, 
#       features are located between any neighbouring 
#       edges that subtend angles less than ETA1 degrees.
#

#   GEOM_ETA1 = 60


#   ---> GEOM_ETA2 - {default=45deg} 2-dim. feature angle, 
#       features are located between any neighbouring 
#       faces that subtend angles less than ETA2 degrees.
#

#   GEOM_ETA2 = 60


#
#   OPTIONAL fields (HFUN):
#   ----------------------
#

#   ---> HFUN_FILE - 'HFUNNAME.MSH', a string containing the 
#       name of the mesh-size file (is required at input).
#       The mesh-size function is specified as a general pi-
#       ecewise linear function, defined at the vertices of
#       an unstructured triangulation or on a structured 
#       grid.
#

#   HFUN_FILE = *.msh


#   ---> HFUN_SCAL - {default='relative'} scaling type for 
#       mesh-size function. HFUN_SCAL='relative' interprets 
#       mesh-size values as percentages of the (mean) length 
#       of the axis-aligned bounding-box (AABB) associated 
#       with the geometry. HFUN_SCAL='absolute' interprets 
#       mesh-size values as absolute measures.
#

#   HFUN_SCAL = ABSOLUTE


#   ---> HFUN_HMAX - {default=0.02} max. mesh-size function 
#       value. Interpreted based on SCAL setting.
#

    HFUN_HMAX = 0.05


#   ---> HFUN_HMIN - {default=0.00} min. mesh-size function 
#       value. Interpreted based on SCAL setting.
#

#   HFUN_HMIN = 0.01


#
#   OPTIONAL fields (MESH):
#   ----------------------
#

#   ---> MESH_DIMS - {default=3} number of "topological" di-
#       mensions to mesh. DIMS=K meshes K-dimensional featu-
#       res, irrespective of the number of spatial dim.'s of 
#       the problem (i.e. if the geometry is 3-dimensional 
#       and DIMS=2 a surface mesh will be produced).
#

#   MESH_DIMS = 2


#   ---> MESH_KERN - {default='delfront'} meshing kernel,
#       choice of the standard Delaunay-refinement algorithm 
#       (KERN='delaunay') or the Frontal-Delaunay method 
#       (KERN='delfront').
#

#   MESH_KERN = DELAUNAY


#   ---> MESH_ITER - {default=+INF} max. number of mesh ref-
#       inement iterations. Set ITER=N to see progress after 
#       N iterations. 
#

#   MESH_ITER = 10000


#   ---> MESH_TOP1 - {default=false} enforce 1-dim. topolog-
#       ical constraints. 1-dim. edges are refined until all 
#       embedded nodes are "locally 1-manifold", i.e. nodes 
#       are either centred at topological "features", or lie 
#       on 1-manifold complexes.
#

#   MESH_TOP1 = TRUE


#   ---> MESH_TOP2 - {default=false} enforce 2-dim. topolog-
#       ical constraints. 2-dim. trias are refined until all 
#       embedded nodes are "locally 2-manifold", i.e. nodes 
#       are either centred at topological "features", or lie 
#       on 2-manifold complexes.
#

#   MESH_TOP2 = TRUE


#   ---> MESH_RAD2 - {default=1.05} max. radius-edge ratio 
#       for 2-tria elements. 2-trias are refined until the 
#       ratio of the element circumradii to min. edge length 
#       is less-than RAD2.
#

#   MESH_RAD2 = 1.50


#   ---> MESH_RAD3 - {default=2.05} max. radius-edge ratio 
#       for 3-tria elements. 3-trias are refined until the 
#       ratio of the element circumradii to min. edge length 
#       is less-than RAD3.
#

#   MESH_RAD3 = 2.50


#   ---> MESH_OFF2 - {default=0.90} radius-edge ratio target
#       for insertion of "shape"-type offcentres for 2-tria
#       elements. When refining an element II, offcentres
#       are positioned to form a new "frontal" element JJ 
#       that satisfies JRAD <= OFF2.
#

#   MESH_OFF2 = 0.95


#   ---> MESH_OFF3 - {default=1.10} radius-edge ratio target
#       for insertion of "shape"-type offcentres for 3-tria
#       elements. When refining an element II, offcentres
#       are positioned to form a new "frontal" element JJ 
#       that satisfies JRAD <= OFF3.
#

#   MESH_OFF3 = 1.25


#   ---> MESH_SNK2 - {default=0.25} inflation tolerance for
#       insertion of "sink" offcentres for 2-tria elements.
#       When refining an element II, "sinks" are positioned
#       at the centre of the largest adj. circumball staisf-
#       ying |JBAL-IBAL| < SNK2 * IRAD, where IRAD is the 
#       radius of the circumball, and [IBAL,JBAL] are the 
#       circumball centres.
#

#   MESH_SNK2 = 0.10


#   ---> MESH_SNK3 - {default=0.33} inflation tolerance for
#       insertion of "sink" offcentres for 3-tria elements.
#       When refining an element II, "sinks" are positioned
#       at the centre of the largest adj. circumball staisf-
#       ying |JBAL-IBAL| < SNK3 * IRAD, where IRAD is the 
#       radius of the circumball, and [IBAL,JBAL] are the 
#       circumball centres.
#

#   MESH_SNK3 = 0.20


#   ---> MESH_EPS1 - {default=0.33} max. surface-discretisa-
#       tion error multiplier for 1-edge elements. 1-edge 
#       elements are refined until the surface-disc. error 
#       is less-than EPS1 * HFUN(X).
#

#   MESH_EPS1 = 0.25


#   ---> MESH_EPS2 - {default=0.33} max. surface-discretisa-
#       tion error multiplier for 2-tria elements. 2-tria 
#       elements are refined until the surface-disc. error 
#       is less-than EPS2 * HFUN(X).
#

#   MESH_EPS2 = 0.25


#   ---> MESH_VOL3 - {default=0.00} min. volume-length ratio 
#       for 3-tria elements. 3-tria elements are refined 
#       until the volume-length ratio exceeds VOL3. Can be 
#       used to suppress "sliver" elements.
#

#   MESH_VOL3 = 0.10


#
#   OPTIONAL fields (OPTM):
#   ----------------------
#

#   ---> OPTM_KERN - {default='odt+dqdx'} mesh optimisation 
#       kernel, choice of an Optimal Delaunay Tessellation 
#       strategy (KERN='odt+dqdx') or a Centroidal Voronoi
#       Tessellation method (KERN='cvt+dqdx'). In both 
#       cases a hybrid formulation is employed, using a 
#       "blend" of the ODT/CVT updates, and gradients of a 
#       "fall-back" mesh quality function Q.
#

#   OPTM_KERN = CVT+DQDX


#   ---> OPTM_COST - {default='area-len'} mesh optimisation
#       cost metric, choice of area-length (COST='area-len') 
#       or skewed-cosine (COST='skew-cos') functions.
#       The area-length metric is symmetric wrt. both small 
#       and large cell angles, and is typically appropriate
#       for simplex-only meshes. The skewed-cosine metric is 
#       based on an asymmetric penalisation of large cell
#       angles, and may be useful for staggered primal-dual 
#       tessellations.
#

#   OPTM_COST = SKEW-COS


#   ---> OPTM_BETA - {default=0.4950} "momentum"-type weight
#       for gradient descent updates, such that
#       DX' = BETA * DX(K-1) + (1-BETA) * DX(K).
#       Momentum typically improves the convergence of mesh
#       optimisation.
#

#   OPTM_BETA = 0.3750


#   ---> OPTM_ZETA - {default=0.8250} "momentum"-type weight
#       for search direction updates, such that
#       DX* = ZETA * DX' (K) + (1-ZETA) * DX(K).
#       Momentum typically improves the convergence of mesh
#       optimisation.
#
  
#   OPTM_ZETA = 0.7500


#   ---> OPTM_ITER - {default=16} max. number of mesh optim-
#       isation iterations. Set ITER=N to see progress after 
#       N iterations.
#

#   OPTM_ITER = 32


#   ---> OPTM_QTOL - {default=1.E-04} tolerance on mesh cost
#       function for convergence. Iteration on a given node
#       is terminated if adjacent element cost-functions are
#       improved by less than QTOL.
#

#   OPTM_QTOL = 1.0E-05


#   ---> OPTM_QLIM - {default=0.9250} threshold on mesh cost
#       function above which gradient-based optimisation is
#       attempted.
#

#   OPTM_QLIM = 0.90


#   ---> OPTM_ZIP_ - {default= true} allow for "merge" oper-
#       ations on sub-faces.
#

#   OPTM_ZIP_ = FALSE


#   ---> OPTM_DIV_ - {default= true} allow for "split" oper-
#       ations on sub-faces.
#

#   OPTM_DIV_ = FALSE


#   ---> OPTM_TRIA - {default= true} allow for optimisation
#       of TRIA grid geometry.
#

#   OPTM_TRIA = FALSE


#   ---> OPTM_DUAL - {default=false} allow for optimisation
#       of DUAL grid geometry.
#

#   OPTM_DUAL = TRUE


#
#   OPTIONAL fields (MISC):
#   ----------------------
#

#   ---> VERBOSITY - {default=0} verbosity of log-file gene-
#       rated by JIGSAW. Set VERBOSITY >= 1 for more output.
#

#   VERBOSITY = 1


#   ---> NUMTHREAD - {default=0} control for thread-parallel
#       implementations. Set NUMTHREAD <= 0 to autodetect a
#       machine's max-thread allocation.
#

#   NUMTHREAD = 4