Class

• <DRM Finite Element Mesh>

Superclass

• <DRM Primitive Geometry>

Subclass

• None.

Definition

An instance of this DRM class specifies a tesselation of a surface into mesh faces, or of a solid into solid elements. Additional data may be associated with each vertex, mesh face, and / or solid element.

More specifically, a <DRM Finite Element Mesh> instance is comprised of:

1. an ordered list of <DRM Vertex> instances, which thus associates an index number to each <DRM Vertex> instance,
2. a <DRM Mesh Face Table> instance, which defines the mesh faces in terms of <DRM Vertex> index numbers,
3. optionally, <DRM Property Table> instances providing additional data (details given below).

Knowledge of which vertices form a mesh face (or solid) is important for various computations, such as interpolation.

Component <DRM Property Table> instances are optional; when present, they are used to define solid elements and to associate data with <DRM Vertex> instances, mesh faces, or solid elements.

Class diagram

Figure 6.100 — DRM_Finite_Element_Mesh

Constraints

• Colour Mapping restrictions
• Continuous LOD restrictions
• Finite Element Mesh structure
• Image Mapping Functions and Texture Coordinates
• Nested Primitive Geometry
• No attribute conflicts
• Non crossing aggregations
• Non cyclic aggregations
• Precedence of Property Set Index
• Publishable Object

Example(s)

• In support of a rain run-off computational model, a ground surface area is triangulated. At each triangle vertex, the gradient, porosity, flow resistance, water capacity, and rain rate are measured.

  This data set is represented in a <DRM Finite Element Mesh> instance by

  1. an ordered list of <DRM Vertex> instances (one for each triangle vertex),
  2. a <DRM Mesh Face Table> to define the triangles, an ECC_MESH_FACE_PROPERTY_SET <DRM Property Table> for the gradient data, and
  3. an ECC_MESH_NODE_PROPERTY_SET <DRM Property Table> for the remaining properties.