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Curves Approximate

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Curves Approximate

Menu location
Curves → Approximate
Workbenches
Curves
Default shortcut
None
Introduced in version
-
See also
None

Description

The Curves Approximate tool approximates points to NURBS curve or surface.

Unlike the Curves Interpolate tool, which aims to generate a curve passing through all points, it aims to create a smoother curve by passing within a specified approximation distance of the points.

Usage

  1. Select one or more objects that contain at least two vertices each.
  2. There are several ways to invoke the tool:
    • Press the Approximate button.
    • Select the Curves → Approximate option from the menu.
  3. An Approximation_Curve object is created for each selected object.
  4. Optionally edit the values in the Property View to choose a different approximation method and parametrization type and also adjust the related properties (see Properties below).

Properties

See also: Property View.

An Approximation_Curve object is derived from a Part Feature object and inherits all its properties. It also has the following additional properties:

Data

Approximate

  • DataPoint Object (Link): Object containing the points to approximate.

General

  • DataApprox Tolerance (Float): Approximation tolerance.
  • DataClamp Ends Tolerance (Bool): Clamps endpoints.
  • DataClosed (Bool): Forces a closed curve.
  • DataContinuity (Enumeration): Desired continuity on the curve.
  • DataDegree Max (Integer): Maximum degree of the curve.
  • Data Degree Min (Integer): Minimum degree of the curve.
  • DataMethod (Enumeration): Approximation method.
    • Parametrization (default): ...
    • Smoothing Algorithm: ...

Parameters

  • DataCurvature Weight (FloatConstraint): Weight of curve curvature for smoothing algorithm.
  • DataLength Weight (FloatConstraint): Weight of curve length for smoothing algorithm.
  • Data Parametrization (Enumeration): Parametrization type.
    • ChordLength (default): ...
    • Centripetal: ...
    • Uniform: ...
    • Curvilinear: ...
  • DataTorsion Weight (FloatConstraint): Weight of curve torsion for smoothing algorithm.

Range

  • DataFirst Index (Integer): Index of first point.
  • DataLast Index (Integer): Index of last point (-1 to ignore).
  • DataStart Offset (Integer): For closed curves, allows to choose the location of the join point.