Class

• <DRM Mesh Face Table>

Superclass

• <DRM SEDRIS Abstract Base>

Subclass

• None.

Definition

An instance of this DRM class is a two-dimensional table that defines the face elements of a <DRM Finite Element Mesh> instance in terms of vertex numbers in the ordered <DRM Vertex> component list of the <DRM Finite Element Mesh> instance and, optionally, the topology of the face elements. The size of the first dimension is provided in the field value total_mesh_faces, while the size of the second dimension is provided in the field value max_nodes_and_rings.

The first data element specifies, for cell i, j, the index in the ordered <DRM Vertex> list of the <DRM Vertex> representing the jth node of the ith mesh face. If the ith mesh face contains less than j nodes, so that j is greater than the number of the last listed node of mesh face i, then the cell data element contains zero (0). The edges of each mesh face i are implicitly defined by pairing node j to node j + 1.

If the field value topology_present is set to TRUE, then the <DRM Finite Element Mesh> instance will contain a second data element in the cell data. The second data element defines surface topology by indicating, for each edge (j, j + 1) of mesh face i, the index of mesh face k (if any) that is adjacent to mesh face i along the edge. A value of 0 indicates an “outside” or “universal” adjacency. A value of i for mesh face i indicates that the edge is artificially connecting an inside perimeter ring to another perimeter ring.

For a given mesh face element index i and mesh face node index j, the (i, j)-th cell gives the vertex number that comprises the j-th node of the i-th mesh face. The mesh face vertices are listed (j index) in clockwise order around the outer perimeter of the mesh face, starting and ending with a first vertex. If inner perimeter rings are present, the vertex list along the second axis continues with inner perimeter vertices in counter-clockwise order starting and ending with a first vertex on each inner ring.

Class diagram

Figure 6.180 — DRM_Mesh_Face_Table

Constraints

• Publishable Object

Example(s)

• Consider six <DRM Vertex> instances, used to define a <DRM Mesh Face Table>, where the mesh would be diagrammed as follows.

  

  Figure 6.181 — <DRM Mesh Face Table> example

  In this example, there are six <DRM Vertex> instances forming the nodes of the mesh, which has three mesh faces (A, B, C).

  The corresponding <DRM Mesh Face Table> instance, without surface topology, would be organized as follows, where each individual cell contains a vertex number.

  Node Number
  	1	2	3	4	5
  1 (Mesh Face A)	1	2	4	1	0
  2 (Mesh Face B)	2	3	6	5	2
  3 (Mesh Face C)	4	2	5	4	0

• Consider the <DRM Mesh Face Table> instance from the previous example, with the addition of surface topology (that is, topology_present set to TRUE. In this instance, each individual cell contains a {vertex number, adjacent mesh face number} pair.

  Node Number
  	1	2	3	4	5
  1 (Mesh Face A)	1, 0	2, 3	4, 0	1, 0	0, 0
  2 (Mesh Face B)	2, 0	3, 0	6, 0	5, 3	2, 0
  3 (Mesh Face C)	4, 1	2, 2	5, 0	4, 0	0, 0