2011
Table Of Contents
- Contents
- Get Information
- The User Interface
- Start and Save Drawings
- Control the Drawing Views
- Organize Drawings and Layouts
- Create and Modify Objects
- Control the Properties of Objects
- Use Precision Tools
- Use Coordinates and Coordinate Systems (UCS)
- Use Dynamic Input
- Snap to Locations on Objects (Object Snaps)
- Restrict Cursor Movement
- Combine or Offset Points and Coordinates
- Specify Distances
- Extract Geometric Information from Objects
- Use a Calculator
- Draw Geometric Objects
- Change Existing Objects
- Select Objects
- Correct Mistakes
- Erase Objects
- Cut, Copy, and Paste with the Clipboard
- Modify Objects
- Modify Complex Objects
- Add Constraints to Geometry
- Define and Reference Blocks
- Work with 3D Models
- Create 3D Models
- Overview of 3D Modeling
- Create Solids and Surfaces from Lines and Curves
- Create Solids
- Create Surfaces
- Create Meshes
- Create Wireframe Models
- Add 3D Thickness to Objects
- Modify 3D Models
- Create Sections and 2D Drawings from 3D Models
- Create 3D Models
- Annotate Drawings
- Work with Annotations
- Hatches, Fills, and Wipeouts
- Notes and Labels
- Tables
- Dimensions and Tolerances
- Understand Basic Concepts of Dimensioning
- Use Dimension Styles
- Set the Scale for Dimensions
- Create Dimensions
- Modify Existing Dimensions
- Add Geometric Tolerances
- Plot and Publish Drawings
- Specify Settings for Plotting
- Save Plot Settings as Named Page Setups
- Reuse Named Page Setups
- Specify Page Setup Settings
- Select a Printer or Plotter for a Layout
- Select a Paper Size for a Layout
- Determine the Drawing Orientation of a Layout
- Set the Plot Area of a Layout
- Adjust the Plot Offset of a Layout
- Set the Plot Scale for a Layout
- Set the Lineweight Scale for a Layout
- Select a Plot Style Table for a Layout
- Set Shaded Viewport and Plot Options for a Layout
- Print or Plot Drawings
- Overview of Plotting
- Use a Page Setup to Specify Plot Settings
- Select a Printer or Plotter
- Specify the Area to Plot
- Set Paper Size
- Position the Drawing on the Paper
- Control How Objects Are Plotted
- Preview a Plot
- Plot Files to Other Formats
- Specify Settings for Plotting
- Share Data Between Files
- Reference Other Drawing Files
- Work with Data in Other Formats
- Collaborate with Others
- Render Drawings
- Draw 2D Isometric Views
- Add Lighting to Your Model
- Materials and Textures
- Render 3D Objects for Realism
- Glossary
- Index
NURBS (Non-Uniform Rational B-Splines) surfaces are part of the suite of 3D
modeling objects that AutoCAD for Mac offers (in addition to 3D solids,
procedural surfaces, and meshes).
NURBS surfaces are based on Bezier curves or splines. Therefore, settings such
as degree, fit points, control vertices, weights, and knot parameterization are
important in defining a NURBS surface or curve. AutoCAD for Mac splines are
optimized to create NURBS surfaces allowing you to control many of these
options (see SPLINE and SPLINEDIT). The illustration below shows the control
vertices that display when you select a NURBS surface or spline.
Two Methods for Creating NURBS Surfaces
There are two ways to create NURBS surfaces:
■ SURFACEMODELINGMODE system variable - Use any of the surface creation
commands while this system variable is set to 1.
■ CONVTONURBS command - Convert any existing surfaces with this
command.
It is important to plan ahead with NURBS modeling, since NURBS surfaces
cannot be converted back into procedural surfaces.
Quick Reference
Commands
CONVTONURBS
Converts 3D solids and surfaces into NURBS surfaces.
502 | Chapter 22 Create 3D Models