Vectorworks 2010 - NURBS; NURBS Tools, Commands, and Basic Operations

Vectorworks 2010 Products 97
Vectorworks Spotlight 2010 Getting Started Guide
NURBS
NURBS is an acronym for Non-Uniform Rational B-Spline. NURBS use rational Bézier curves and a non-uniform explicitly given knot
vector. Degree, control points, knots, and an evaluation rule are needed to specify a NURBS curve. Sounds awfully complex. Especially
for a Getting Started book. I have found that in the entertainment business, we have to draw some pretty complex objects. NURBS may
not always be the right choice, but they are an important option.
Remember, NURBS always draw curves, so if precise straight lines are crucial, be careful of your choices. NURBS can be manipulated
in many ways, even if they aren’t the right choice, they may offer you some unique options for layout and plotting 3D Locus points for
modeling with 3D Polys.
We have already worked with Bézier Curves when manipulating 2D Polygons with the 2D Reshape Tool, so there should be some
familiarity. Most of the other modeling tools we have looked at create solid objects. It is important to remember that NURBS objects are
not solids, they are dened pure geometric planes in 3D space. They have no dened thickness. NURBS objects uniquely combine
ease of drawing and precision.
You will nd NURBS Tools in the 3D Modeling Toolset and NURBS Commands accessible Model>3D Power Pack. You can also
convert a 2D or 3D object to a NURBS object by selecting it and going to Modify>Convert>Convert to NURBS.
One general and very important note. Every NURBS point can be specically absolutely positioned in 3D Space from the OIP.
This
precision allows for the creation of some very elegant objects. Free form objects can be created with the 3D Reshape Tool.
The Landmark module of Vectorworks designer allows for the creation of free form land forms. Useful in the production of many plays.
The Digital Terrain Modeling relies heavily on NURBS.
Also refer to the NURBSdemo.vwx le included.
NURBS Tools (from the Toolset)
NURBS Arc•
NURBS Circle•
NURBS Curve•
Fillet Edge•
Chamfer Edge•
Solid Shell•
Protrusion Cutout•
Loft Surface•
Extract Surface•
Create Contours•
Project•
Analysis•
NURBS Commands
(from the 3D Power Pack)
Stitch & Trim Surface•
Create Filet Surface•
Create Surface from Curves•
Create Drape Surface•
Create Helix Spiral•
Revolve with Rail•
Create Interpolated Surface•
Extend NURBS•
Rebuild Nurbs•
Unfold Surfaces•