Questions tagged [nurbs]

Non-uniform rational basis spline (NURBS) is a mathematical model commonly used in computer graphics for generating and representing curves and surfaces which offers great flexibility and precision for handling both analytic and freeform shapes.

Non-Uniform Rational B-Spline (NURBS) is a mathematical model commonly used in computer graphics and computer aided design for representing curves and surfaces which offers great flexibility and precision for handling both analytic and freeform shapes.

NURBS allow representation of geometrical shapes in a compact form. They can be efficiently handled by the computer programs and yet allow for easy human interaction. NURBS surfaces are functions of two parameters mapping to a surface in three-dimensional space. The shape of the surface is determined by control points.

NURBS are commonly used in computer-aided design (CAD), manufacturing (CAM), and engineering (CAE) and are part of numerous industry wide used standards, such as IGES, STEP, ACIS, and PHIGS. NURBS tools are also found in various 3D modeling and animation software packages, such as form•Z, Blender,3ds Max, Maya, Rhino3D, Cinema 4D, Cobalt, Shark FX, and Solid Modeling Solutions. Other than this there are specialized NURBS modeling software packages such as Autodesk Alias Surface, solidThinking and ICEM Surf.

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Distance of a Point to a NURBS Surface

I am looking for an easy way to compute the minimum distance of a point to a nurbs surface with matlab. I am looking for the closest point => not an orthogonal projection. I have read about the concept of sampling to get a start and then do newton…
Sandra C.
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Maya transform node not appearing in list

The Maya python code below gives a nurbs boolean surface by first taking the difference of two nurbs spheres, nurbsSphere1 and nurbsSphere2, to give the nurbs surface nurbsBooleanSurface1. It then takes the difference of this surface and a third…
svenpables
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Python, how to convert spline defined by x;y list of point into NURB curve

is possible to convert the (x;y) coordinates system into a NURBS definition control points and knots? The main idea is that I'm trying to develop a modeling tool in python for air wind generator and I want mathematically model the blades as a NURBS…
efirvida
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point evaluation of NURBS curve given an axial coordinate

my question is how to get the second coordinate (in 2D) of a point that lies on a curve defined as a NURBS curve given the axial coordinate. I have the knot vector, control points, their weights and basis functions. I looked through similar…
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Creating a smooth nurb from list of points

I am developing a 3D graphic application in which the user can draw curves. I record the curve that is drawn by the user and i would like to create a smooth nurb from the recorded set of points. I tried using the openNurbs library but i could not…
Erik Sapir
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GLU NURBS - how to set control point weights?

I'm writing a NURBS class that uses OpenGL's GLU extension to do rendering, but I just realized I have no idea how to set the control point weights. It's not in the Red Book or the GLU documentation, and the web doesn't mention much of it, either. …
Kyle Simek
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Any Java graphics library library with NURBS, homogeneous coordinates and perspective?

Are there any Java graphics libraries which support NURBS, homogeneous coordinates and perspective transform? I need 2D. Better if this library will be an extension of something standard like java.awt.geom.
Suzan Cioc
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Generate a Approximated NURBS surface from a point cloud

I have to write a C++ program that, from a list of unorganized point, calculates the approximate surface on which these points lie and generate the corresponding NURBS. I've already seen OpenNurbs but there are no function for this, and libNURBS but…
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OpenGL Nurbs: finding knot coordinates

I need to draw the control points and knots of a NURBS curve, in OpenGL. The control points are no problem, as they are defined by their coordinates. I'm having a bit more trouble with the knots, however. I have an array of knots as taken by the…
Joost
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NURBS library for Delphi

Could you recommend some library to manipulate splines available for Delphi? I've done some searching but all I've found had C/C++/Python bindings. The features I need are: manipulating splines in 2D: rotate, translate, mirror, scale and also…
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How to impose C1 continuity while generating NURBS Surfaces?

I'm fitting NURBS surfaces onto some data points in the form of patches. I have a certain amount of patches and a uniform resolution of 17x17 data points per patch. The degree values are 3 in each direction. Every patch is fit NURBS surface using a…
Emre Turkoz
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Linking error when including file containing array

I have the following code in my class object: void Object::drawSurface() { GLUnurbsObj *nurbSurface; nurbSurface = gluNewNurbsRenderer(); gluNurbsProperty( nurbSurface, GLU_SAMPLING_TOLERANCE, 25.0 ); gluNurbsProperty( nurbSurface,…
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NURBS curve for arc

I tried to implement NURBS to describe a circular arc (1/4 of arc here). Unfortunately, the NURBS curve is a bit a far from the real arc. I was expecting it would be more closed same as here, for example, https://nurbscalculator.in/ or in scientific…
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NURBS/B-Spline Visualization with geomdl 3D not working (shows empty image)

I need to create NURBS surfaces for a project. For that i want to use the geomdl package. I installed it via conda and i tried it with the examples given here. It works with the 2d examples but not with the 3d examples. This is a Code for a B-Spline…
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How do I generate Bezier Curves and NURBS in C++ and import it as an igs?

I am new to C++ NURBS libary. I learnt generating line (by CLine, from nurbs.h ) and save it as igs. But in case of multiple control points, how to generate a curve ? Every other tutorial using graphics.h (putpixel), but couldnt find anything about…
san
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