Curves Module

Parent module: Geometry Module

group a3d_crv

Creates and accesses entities that represent geometric curves.

Geometric curves (A3DCrvBase) are a mandatory part of the topology construct in an A3DTopoBody entity. Do not confuse an A3DCrvBase entity with an A3DRiCurve entity. The latter is a particular representation item that has an A3DTopoSingleWireBody as its topology entry point.

All curves are defined as described in these steps:

1. Define the canonical form of the whole curve.

2. Define the actual parameterization and the portion of curve (trimming information) (A3DParameterizationData).

3. Define the orientation and scaling of the curve using a Cartesian transformation. The transformation cannot specify mirror or non-uniform scaling transformations (see A3DMiscCartesianTransformationData).

Here are definitions for terms that apply to curves.

• Curve is a mathematical description for a whole curve.

• Arc is a portion of a curve corresponding to an interval.

Sub-modules

NURBS Curve	Entity type is kA3DTypeCrvNurbs .
Linear Curve	Linear Curve
Circular Curve	Circular Curve
Elliptic Curve	Elliptic Curve
Parabolic Curve	Parabolic Curve
Hyperbolic Curve	Hyperbolic Curve
Polyline Curve	Polyline Curve
Composite Curve	Composite Curve
Equation Curve	Equation Curve
Transform Curve	Transform Curve
Curve On Surface	Curve On Surface
Offset Curve	Offset Curve
Helix Curve	Helix Curve
Intersection Curve	Intersection Curve
Blend02Boundary Curve	Blend02Boundary Curve