fast command

Syntax

region ID mesh/test/fast args region-keyword region-arg ...

ID = user-assigned name for the region
args = file filename scale s move offx offy offz rotate phix phiy phiz
file = obligatory keyword filename = name of ASCII VTK file containing the VTK tet-mesh data scale = obligatory keyword s = scaling factor for the mesh (dimensionless) move = obligatory keyword offx,offy,offz = offset for the mesh (distance units) rotate = obligatory keyword phix,phiy,phiz = angle of mesh rotation around x-, y-, and z-axis (in grad)
zero or more region-keyword/region-arg pairs may be appended which are documented in region

Examples

region  mesh mesh/tet/fast file Cut_1_fine.vtk  scale 0.001 move 0. 0. 0.05  rotate 0. 0. 0. units box

Description

This command defines a geometric region of space. Various other commands use regions, and a variety of other region styles exist as well. See region command for details.

For style mesh/tet/fast (this command), a tetrahedral mesh can be read from an ASCII VTK file. You can apply offset, scaling and rotation to the imported mesh via dedicated keywords. If applying more then one of these operations, the offset is applied first and then the geometry is scaled. Then the geometry is rotated around the x-axis first, then around the y-axis, then around the z-axis.

Further keywords are described in the doc of the region command.

mesh/tet/fast is similar to mesh/tet (as described in region command), but the mesh insertion routines are optimized for better performance

Warning

Currently only ASCII VTK containing tetrahedra are supported. For periodic boundaries, the mesh is NOT mapped. Instead, a warning is generated if a vertex lies outside the simulation box.

Restrictions

Currently, option “all_in = yes” of the fix insert/* commands do not work with region mesh/tet/fast.

Default

The option defaults are side = in, units = box, and no move or rotation.