Data Type: Tetra Grid ()

Description:

A data object of type Tetra Grid represents an unstructured finite-element grid composed of tetrahedra. The geometric information is stored in terms of vertices, edges, faces, and tetrahedra. For instance such data objects are useful as patient models. Like a Label Field with its uniform hexahedral grid structure a tetrahedral grid also contains a 'dictionary' of different material types or regions. In addition to the material names the dictionary may contain colors and other parameters related to material properties.

is able to reconstruct tetrahedral grids from 3D image data. This procedure involves several steps, including image segmentation, extraction of boundary faces, surface simplification, and finally grid generation. The tutorial in Section "Creating a Tetrahedral Grid from a Triangular Surface" of the user's guide illustrated this process in more detail. The actual grid generation step is performed by the computational module Generate Tetra Grid. The quality of a tetrahedral grid may be improved by applying certain operations provided by the Grid Editor.

Commands:

hasMaterial <name>
Returns true if the specified material is defined in the material section of the Tetra Grid.

hasDuplicatedNodes
Returns the number of duplicated nodes, i.e., nodes with exact identical coordinates. Such nodes may be used in order to represent discontinuous piecewise linear fields.

removeDuplicatedPoints
Removes all duplicated points from the grid. No field object must be connected to the grid.

add <othergrid>
Copies all vertices and tetrahedra from an other tetrahedral grid into this one.

removeTetra <n>
Marks the tetrahedral cell specified by <n> as obsolete.

cleanUp
Removes all obsolete tetrahedra from the grid.

fixOrientation
Fixes the orientation of all tetrahedra so that the enclosed volume is positive.