`block generate`

command

Syntax

- block generate keyword
Primary keywords:

from-vrml from-geometry from-topography break-angle direction geometry-set plane ratio segments voronoi

Generate an assembly of blocks. The method for block creation is determined by the first keyword used.

- from-vrml keyword
Create blocks defined by a block geometries in a VRML file (Virtual Reality Modeling Language). Shapes in the VRML file must be closed, convex surfaces. The file must be in VRML 2.0 format. m ,,,

- break-angle f
Specify the angle between faces below which two separate faces are merged. The default is 1 degree.

- filename s
Specify the filename of the VRML file.

- from-geometry keyword
Create tetrahedral blocks to fill a closed volume defined by a geometric set.

- cut-angle f
Threshold angle for the capture of surface features. The default value is 45°. Use a larger cut angle smooth over unwanted surface features associated with the coarseness of the triangulation. Use a smaller cut angle if there are intersecting surfaces after surface remeshing.

- gradation-surface f
Rate at which, on the surface of the tetrahedral mesh, neighboring triangle sizes vary as triangles increase or decrease in size due to local size adaptation

- gradation-volume f
Rate at which neighboring tetrahedra will increase in size away from the surface.

- maximum-edge f
Specify the maximum edge length for any tetra to be generated. The actual maximum edge length will be close to this, but the result is not guaranteed to be exact.

- minimum-edge f
Specify the minimum edge length for any tetra to be generated. The actual minimum edge length will be close to this, but the result is not guaranteed to be exact.

- merge
If specified, all the blocks in the same groups will be merged in one block

- set s
Specify the geometry set used to define the surface. By default, the current geometric set will be used.

- from-topography <keyword ...> <range>
Generates blocks by extruding surface faces in the range until they meet polygons in a geometric set. Block faces could be triangulated if they are not planar.

- break-angle f

Set a break angle greater than 0 to simplify the geometric set by merging triangular faces if the angle between them is less the f. The default is 0.

- direction v

Specify the extrusion direction that will be used to create blocks on surface faces. From a surface gridpoint, a ray will be cast in this direction until it intersects a polygon in the geomtric set. This will define the shape and size of the blocks created. By default this value will be (0,0,1). If a face normal is parallel to this direction vector (with a tolerance of about 0.5 degrees) the face will be neglected even it if is in the range.

- geometry-set s

Specify the geometry set used to define the surface to which blocks are being extruded. By default the current geometric set will be used.

- group s1 <slot s2 >
Assign the group s1 to the created blocks, in slot s2. If not specified, the default slot is Default. Use of the group logic is described in Groups.

- plane keyword
- Give the
`plane`

keyword to indicate that the extrusion is to a plane rather than a geometric set. The plane must be defined by a`normal`

and`origin`

.- normal v
Give the normal to the plane to which you are extruding if

`plane`

is specified.

- origin v
Give the origin of the plane to which you are extruding if

`plane`

is specified.

- ratio f

Specify the ratio used to distribute blocks from the surface face to the geometric set. A ratio of 1.1 means that each block edge in that direction will be 1.1 times the length of the previous block. So, by default, a ratio of > 1 means blocks will get larger in the positive \(z\) direction. If not specified, the default ratio is 1.0.

- segments i

Specify the number of blocks layers created between the existing surface block faces and the geometry set. By default this value is 1.

- voronoi keyword
Create Voronoi blocks to fill a closed volume defined by a geometric set (restricted surface).

- cut-angle f
Threshold angle for the capture of surface features. The default value is 45°. Use a larger cut angle smooth over unwanted surface features associated with the coarseness of the triangulation. Use a smaller cut angle if there are intersecting surfaces after surface remeshing.

- gradation-surface f
Rate at which, on the restricted surface, distance between two seeds vary (increase or decrease) in size due to local size adaptation

- gradation-volume f
Rate at which distance between two seeds will increase in size away from the restricted surface.

- maximum-edge f
Specify the maximum distance between two seeds. The actual maximum distance will be close to this, but the result is not guaranteed to be exact.

- minimum-edge f
Specify the minimum distance between two seeds. The actual minimum distance will be close to this, but the result is not guaranteed to be exact.

- set s
Specify the geometry set used to define the restricted surface. By default, the current geometric set will be used.

Was this helpful? ... | 3DEC © 2019, Itasca | Updated: Mar 31, 2021 |