Entity Types for Mesh Creation

The available entity types for Mesh creation (shown in the graphic below) are explained in the following segment.

Line

Line is the default entity type. Line meshes are especially useful in the development of complex intersections. You can edit the lines that make up the mesh and change them to fit the shape of the intersection. As is true with any mesh, the representation of the actual part becomes more accurate when more entities are used to define it.

Remember that lines are linear entities, so you cannot depend on them to represent the actual curvature of an object absolutely. You can use the positional data at the intersections of the lines of the mesh as part of the curve of the object.

Point

Points are useful for illustrating complex curves because they show the intersections of many meshing entities, creating an accurate representation of an object.

Polyline

Polyline meshes are made up of a single, continuous entity that changes direction at each boundary of the mesh. The polyline mesh is a single entity; you cannot edit it. The polyline mesh can contain a number of different direction changes; each of which can contain a block of information. Because the polyline is a single entity, it does not require large amounts of repetitive information. Using a polyline mesh to show true contours of an object is limited, since a polyline is a linear entity.

PGon3

Polygon meshes provide positional data, and can also be input into analysis applications. They define complex surfaces for use with solid modeling. You define each polygon mesh in the same direction to define a normal, which can be reversed if the mesh is grouped. The entities might not look like they've changed, but the normals will be reversed. This helps you create correct geometry to export to presentation graphics software.

This option is used to create a three-sided polyline mesh in polygonal form.

PGon4

Polygon meshes provide positional data, and can also be input into analysis applications. They define complex surfaces for use with solid modeling. You define each polygon mesh in the same direction to define a normal, which can be reversed if the mesh is grouped. The entities might not look like they've changed, but the normals will be reversed. This helps you create correct geometry to export to presentation graphics software.

This option is used to create a four-sided polyline mesh in polygonal form.

Spline

Because a spline mesh follows a set of curves more closely than any other type of mesh, it needs more information than other mesh types. Due to the magnitude of information needed to create a spline mesh, it may take the most time to process.

The Spline option creates a cubic parametric spline. When creating this mesh type, it will be important to keep the following in mind:

• All node points of the spline mesh lie on the actual surface.

• The more segments you specify, the more accurate the spline representation of the surface will be.

• Spline segments that are considered too small will not be added to the database.

NURBS

NURBS Curves are generic rational B-spline curves, and are the standard spline entity. Like the cubic parametric spline above, the NURBS type might require more information to define it than other mesh types.