NonUniform B-Spline (NURBS) is a method to describe parametric curves/surfece. TYpically used as base poriniteves in CAD modelling.
Questions tagged [nurbs]
22 questions
10
votes
1 answer
Non-uniform rational B-spline (NURBS) Basics
I'm trying to understand NURBS curves (surfaces later!) but I have some trouble understanding the very basics of its inner workings. Could someone please explain a few things to me? As I come from Bezier curves, a comparison between these two would…
Ecir Hana
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9
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1 answer
Splitting of NURBS curves
Splitting Bezier curve into two parts at some parameter t is easy thanks to De Casteljau's algorithm.
Is there a similar algorithm for NURBS curves? How to split a NURBS curve?
Ecir Hana
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8
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1 answer
NURBS knot multiplicity
In Splitting of NURBS curves there the answer relied on "maximum knot multiplicity". In order not to mix-up different topics I would like to kindly ask to answer it in another question: what is this "knot multiplicity" all about?
Ecir Hana
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7
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1 answer
NURBS curve drawing
How to draw a NURBS curve?
Compared with Bezier curve, I just evaluate the Bernstein polynomial, multiply it with control point positions and that's it.
Looking at the "General form of a NURBS curve" paragraph of NURBS Wikipedia page I have a hard…
Ecir Hana
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6
votes
1 answer
NURBS curve offset
One of the benefits of NURBS curve over, say Bezier curve, is the ability to create offset curves exactly. How to proceed with such computation? Do I just translate the control points?
Ecir Hana
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3
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drawing NURBS: knots, multiplicity, divide by zero?
I'm trying to grasp how NURBS curves work. I think I understand the principle, but I'm unsure about the formula. Here, I base myself on this course.
From a DXF file, I got the following parameters:
knots (7): [0,0,0,0.5,1,1,1]
degree: 2
closed:…
tgirod
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