Sketcher BSplineKnotenVielfachheitVerringern

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Sketcher BSplineKnotenVielfachheitVerringern

Menüeintrag
Skizze → B-Spline-Werkzeuge → Vielfachheit eines Spline-Knotens verringern
Arbeitsbereich
Sketcher
Standardtastenkürzel
Keiner
Eingeführt in Version
0.17
Siehe auch
BSplineKnotenVielfachheitErhöhen

Beschreibung

Das Werkzeug Sketcher BSplineKnotenVielfachheitVerringern verringert die Vielfachheit eines B-Spline-Knotens.

Anwendung

  1. Einen B-Spline-Knoten auswählen.
  2. Es gibt mehrere Möglichkeiten, den Befehl aufzurufen:

Beispiel

See Sketcher_BSplineIncreaseKnotMultiplicity

Notes

If you decrease the multiplicity of a knot to zero, the knot vanishes. Mathematically it then appears zero times in the knot vector, meaning there is no longer a basis function. Understanding this requires some math, but it will also be clear if you look at the multiplicity. For example a knot with multiplicity 0 on a B-spline with degree 3 means that at the position of the knot two Bézier pieces are connected with C3 continuity. So the third derivative should be equal on both sides of the knot. However for a cubic Bézier curve this means that both sides must be part of the same curve. There is then effectively no longer a knot connecting two Bézier curves.