Description

IMPEXP_STL Import/export geometry or grid in STL format.

[ OUT ] = IMPEXP_STL( FILE_NAME, MODE, DATA, VARARGIN ) Import and export of CAD geometries and meshes in STL format. Both 3D and planar 2D geometries are supported (planar STL data will be converted to 2D geometry objects).

FILE_NAME can either be a string to specify the file name to process, or a cell array of strings specifying several STL files. where in each file can be parsed in to separate subdomains or boundary regions.

MODE is a string indicating either IMPORT or EXPORT. For the default IMPORT mode option the function returns a FEATool geometry struct, grid struct, or unprocessed STL data. For export a postfix string (for example export_R1) can be used to assign a specific geometry object to export (and not split 3D boundaries to solid sections). The RAW flag can be used to return an unprocessed geometry object, or the STL vertices and facets.

During export, DATA can either be a FEATool finite element geometry or mesh struct to export to STL format. For 3D import DATA is an optional geometry struct where the objects are used to assist with assigning and matching facets to boundaries (instead of using solid sections or mesh analysis to group facets). An additional optional logical field nrev in the geometry object structs is supported for reversing of the reference normals (due to subtraction csg operation).

Accepts the following optional property/value pairs during import.

Property    Value/{Default}           Description
-----------------------------------------------------------------------------------
solid       scalar  {1}               Solid section processing
                                         0 - Merge solid sections and analyze mesh
                                         1 - Perform mesh analysis without merging
                                         2 - Assign solid sections as boundaries
fsubd       logical {false}           Process files as separate subdomains
                                      Mesh analysis parameters (see MESH_ANALYZE)
tol_th      array   {[30,10,160,20]}     Angle tolerances for feature detection
tol_ar      array   {[3,1,1.5]}          Aspect ratio tolerances
tol_co      array   {[2,30]}             Path coalescence parameters
sharp       integer {2}               Split regions with sharp edges
extend      logical {true}            Extend/grow unconnected edges
raw         integer {0}               1 = Import raw STL geometry object,
                                      2 = Import raw STL data (vertices, facets)
check       logical {true}            Check boundary connectivities

See also: mesh_repair, mesh_analyze