Class Name: Finite Element Mesh

Superclass - <Primitive Geometry>

Subclasses

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 <Finite Element Mesh> instance is comprised of:

1. an ordered list of <Vertex> instances, which thus associates an index number to each <Vertex> instance,
2. a <Mesh Face Table> instance, which defines the mesh faces in terms of <Vertex> index numbers,
3. optionally, <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 <Property Table> instances are optional; when present, they are used to define solid elements and to associate data with <Vertex> instances, mesh faces, or solid elements.

Primary Page in DRM Diagram:

• 5

Secondary Pages in DRM Diagram:

• 18

Example

1. 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 <Finite Element Mesh> instance by

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

FAQs

What is the difference between a surface and a solid <Finite Element Mesh>?

Surface mesh does not have any <Property Table> instances classified as either ECC_MESH_SOLID_SET or ECC_MESH_SOLID_PROPERTY_SET, but may have surface topology in its component <Mesh Face Table>.

A solid mesh shall have a ECC_MESH_SOLID_SET <Property Table>, may have a ECC_MESH_SOLID_PROPERTY_SET <Property Table>, and does not have surface topology in its component <Mesh Face Table>.

As a user, where can users obtain further information about <Finite Element Mesh> and its associated <Data Table> instances?

See Part 4 Volume 6, Data Tables Technical Guide, of the SEDRIS Documentation Set.

Constraints

• <<Publishable Object>>
• <<No Attribute Conflicts>>
• <<Non Crossing Aggregations>>
• <<Non Cyclic Aggregations>>
• <<Precedence of Property Set Index>>
• <<Colour Mapping Restrictions>>
• <<Continuous LOD Restrictions>>
• <<Image Mapping Functions and Texture Coordinates>>
• <<Nested Primitive Geometry>>
• <<Finite Element Mesh Structure>>

Composed of (two-way) (inherited)

• zero or one <Classification Data> instance
• zero or more {ordered} <Property Set Index> instances
• zero or more <Property Table> instances
• zero or more <Property Table Reference> instances
• zero or more <Property Value> instances
• zero or more <Colour> instances
• zero or more {ordered} <Image Mapping Function> instances
• zero or one <Light Rendering Properties> instance
• zero or one <Presentation Domain> instance
• zero or one <Rendering Priority Level> instance
• zero or one <Rendering Properties> instance
• zero or more <Tack Point> instances
• zero or one <Union Of Primitive Geometry> instance (notes)

Composed of (two-way)

• one <Mesh Face Table> instance
• 3 or more {ordered} <Vertex> instances (notes)

Composed of (two-way metadata) (inherited)

• zero or one <Time Constraints Data> instance

Component of (two-way) (inherited)

• zero or more <Union Of Primitive Geometry> instances

Inherited Field Elements

Notes

Composed of Notes

Union_Of_Primitive_Geometry

 A <Primitive Geometry> instance contains a
 <Union Of Primitive Geometry> instance as a component only
 when that <Primitive Geometry> instance can be decomposed
 into nested <Primitive Geometry> instances, as (for
 example) a <Polygon> instance can be decomposed into
 subfaces.

Vertex

 Since a <Vertex> shall have a <Location>, this provides
 an enumerated collection of <Location> instances.