Sketcher CreatePeriodicBSplineByInterpolation: Difference between revisions

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(Limitations: linking to Sketcher_CreateBSplineByInterpolation.)
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==Limitations==
==Limitations==


See [Sketcher_CreateBSplineByInterpolation#Limitations|Sketcher CreateBSplineByInterpolation].
* The resultant curve is no different than the curve defined through control points. So all limitations of a periodic B-spline apply.
* The B-splines created are always cubic (i.e. with degree 3).
* The defined multiplicity may not always be respected
** For a periodic spline, the first knot (coincident with last) always has a multiplicity of 2.
** If the points just before and just after have multiplicities >=3, the piece between these two is fully continuous, and this (middle) point will only be constrained with point-on-object. If a knot is needed, consider using the insert knot tool.





Revision as of 10:30, 3 June 2023

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Sketcher CreatePeriodicBSplineByInterpolation

Menu location
Sketch → Sketcher geometries → Interpolate periodic B-spline
Workbenches
Sketcher
Default shortcut
G B O
Introduced in version
0.21
See also
Sketcher periodic B-spline

Description

This tool creates a periodic B-spline curve passing through given points. See this page for more info about B-splines.

Usage

  1. Press the Periodic B-spline by knots button.
  2. Create a series of points by clicking in the 3D view. While the command is active, the created points are connected with straight lines.
  3. Optionally press M before terminating the input to define the multiplicity of the knot at the last defined point (note that this may not always be respected; see limitations for details).
  4. Optionally press Backspace before terminating the input to delete the last created control point.
  5. Right-click to terminate the input and generate the curve.
  6. Depending on preferences, the tool may remain active to trace a new curve. Right-click again to exit the command.

Notes

See Sketcher CreateBSpline.

Limitations

See [Sketcher_CreateBSplineByInterpolation#Limitations|Sketcher CreateBSplineByInterpolation].