Class Name: Finite Element Mesh

Superclass - <Primitive Geometry>

Subclasses

Definition

An instance of this DRM class specifies a tessellation 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.

A <Finite Element Mesh> instance is comprised of:

1. an ordered list of <Vertex> components where the position in the ordering forms an index number to each <Vertex> component,
2. a <Mesh Face Table> component that defines the mesh faces in terms of the index numbers of the <Vertex> components, and
3. optionally, <Property Table> components providing additional data (details given below).

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

<Property Table> components 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 environmental data is represented in a <Finite Element Mesh> instance by:

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

FAQs

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

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 <Mesh Face Table> component.

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

Where can users obtain further information about <Finite Element Mesh> instances and their associated <Data Table> instances?

See P4V6 of the SEDRIS Documentation Set.

Constraints

• <<Publishable Object>>
• <<Constraints On Components>>
• <<Non Cyclic Aggregations>>
• <<Precedence of Property Set Index>>
• <<Property Constraints>>
• <<Colour Mapping Constraints>>
• <<Continuous LOD Constraints>>
• <<Image Mapping Functions and Texture Coordinates>>
• <<Nested Primitive Geometry>>
• <<Presentation Domain Constraints>>
• <<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> instance¹

Composed of (two-way)

• one <Mesh Face Table> instance
• 3 or more {ordered} <Vertex> instances²

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

EXAMPLE  A <Polygon> instance can be decomposed into multiple <Polygon> instances representing subfaces.

Vertex