2012
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
- Work with the User Coordinate System (UCS)
- Enter Coordinates to Specify Points
- 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
- Create Objects
- Select and Modify Objects
- Select Objects
- Correct Mistakes
- Erase Objects
- Cut, Copy, and Paste with the Clipboard
- Modify 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 Drawings from 3D Models
- Create 3D Models
- Annotate Drawings
- Work with Annotations
- Overview of Annotations
- Scale Annotations
- Overview of Scaling Annotations
- Set Annotation Scale
- Create Annotative Objects
- Display Annotative Objects
- Add and Modify Scale Representations
- Set Orientation for 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
- Work with Annotations
- 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
- Publish Drawings
- 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
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.
See also:
Create Solids and Surfaces from Lines and Curves (page 361)
Create Surfaces from Other Surfaces (page 398)
Edit NURBS Surfaces and Curves (page 493)
Rebuild NURBS Surfaces and Curves (page 494)
Draw Splines (page 209)
Modify Splines (page 281)
Using the Spline tool to create NURBS Surfaces
and Splines
The spline tool is optimized to work with NURBS modeling
NURBS surfaces can be created from a number of 2D objects, including edge
subobjects, polylines, and arcs. But the spline tool is the only object that has
options that are compatible with creating NURBS surface. Not only do splines
consists of Bezier arcs, but they also can be defined with both control vertices
and fit points. The fit points and control vertices offer different editing options
such as knot parameterization and degree options.
Moving Fit Points vs. Moving Control Vertices
NURBS curves have both fit points and control vertices. The fit points lie on
the line, and the control vertices lay outside the line. Use fit points to make
a change to one small part of a curve; use control vertices to make changes
that will affect the shape of the curve as a whole.
404 | Chapter 8 Work with 3D Models