Sketcher BSplineDecreaseKnotMultiplicity/it

Aumentare la molteplicità di nodi di una BSpline

Spazio virtuale

Sketcher

Diminuisci la molteplicità
Posizione nel menu
Sketch → Strumenti B-spline → Diminuisci la molteplicità
Ambiente
Sketcher
Avvio veloce
Nessuno
Introdotto nella versione
0.17
Vedere anche
Crea B-spline

Descrizione

Diminuisce la molteplicità del nodo di curva B-spline (vedere: B-spline).

Utilizzo

1. Selezionare un nodo di una B-spline
2. Richiamare lo strumento usando uno di questi metodi:
   • Premere il pulsante Diminuisci la molteplicità nella barra degli strumenti.
   • Usare la voce Sketch → Strumenti B-spline → Diminuisci la molteplicità dal menu principale.

Example

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.

Aumentare la molteplicità di nodi di una BSpline

Spazio virtuale

Sketcher

Sketcher

• General: Create sketch, Edit sketch, Map sketch to face, Reorient sketch, Validate sketch, Merge sketches, Mirror sketch, Leave sketch, View sketch, View section, Toggle grid, Toggle snap, Configure rendering order, Stop operation

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• Sketcher geometries: Point, Line, Arc, Arc by 3 points, Circle, Circle by 3 points, Ellipse, Ellipse by 3 points, Arc of ellipse, Arc of hyperbola, Arc of parabola, B-spline by control points, Periodic B-spline by control points, B-spline by knots, Periodic B-spline by knots, Polyline, Rectangle, Centered rectangle, Rounded rectangle, Triangle, Square, Pentagon, Hexagon, Heptagon, Octagon, Regular polygon, Slot, Fillet, Corner-preserving fillet, Trim, Extend, Split, External geometry, Carbon copy, Toggle construction geometry

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• Sketcher B-spline tools: Show/hide B-spline degree, Show/hide B-spline control polygon, Show/hide B-spline curvature comb, Show/hide B-spline knot multiplicity, Show/hide B-spline control point weight, Convert geometry to B-spline, Increase B-spline degree, Decrease B-spline degree, Increase knot multiplicity, Decrease knot multiplicity, Insert knot, Join curves

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