NURBS Lesson 2: Introduction|In addition to creating NURBS surfaces using curves

Editing a revolve surface
After you create a surface from a revolved curve, you can reshape the original creation curve to reshape
the surface. This is possible because Maya's Construction History feature was turned on before you did
the revolve operation.

Selecting the original creation curve can be challenging when it is situated amongst other existing curves
and surfaces. The Outliner is an editor that is useful for quickly examining the structure and components
of a scene. The Outliner is also useful for selecting objects in situations like this.

To edit a surface with construction history
1. Select Window > Outliner.
The Outliner appears and displays a list of the items in the scene.

2. In the Outliner, select the curve you revolved (curve1) by clicking on its name in the list.
The curve becomes highlighted in the scene views.

3. In the front view, right-click in the view and select Control Vertex from the marking menu.
The CVs for the curve appear.

4. Select and move one or more CVs to adjust the curve shape as desired.
If you have trouble selecting one of the CVs in the front view, select it in the perspective view
after dollying and tumbling the camera as necessary.

This modifies the shape of the egg holder because it is linked to the shape of the curve by its
construction history.

5. If desired, save the scene for future review.

6. Close the Outliner window.

NURBS Lesson 1: Beyond the lesson

In this lesson you were introduced to a few basic techniques related to NURBS modeling:

 Revolving a curve is the easiest way to create surfaces with radially symmetrical forms— wheels,
vases, glasses, pillars, and so on.
 NURBS surfaces are webs of interconnected curves. The creation curves are used to create and
subsequently modify the surfaces if required.
 Proficiency at drawing and editing curves is an important part of NURBS modeling.
 The grid is a useful aid for constructing and modifying curves.

Some additional points you should know are:

 You cannot render curves, so your work with them is always an adjunct to creating and editing
surfaces.
 Besides moving a curve's CVs to alter its shape, you can cut, attach, extend, close, and smooth
curves.
 After you create a surface from a revolved curve, you can edit the surface at a component level
by moving CVs or scaling groups of CVs on that surface to customize the shape of the surface.
(You will need to turn off construction history in order to do this.)

NURBS Lesson 2: Introduction

In addition to creating NURBS surfaces using curves, you can edit and sculpt surfaces and primitive
objects in Maya using the Sculpt Geometry Tool.

The Sculpt Geometry Tool allows you to interactively push or pull on the surface regions to create areas
that are embossed or in relief in relation to the surface.

In this lesson, you learn some of the basic concepts of these tools by sculpting a cartoon face and head
from a NURBS primitive sphere using the Sculpt Geometry Tool.

In this lesson you learn:
 Basic sculpting operations (push, pull, smooth, and erase) with the Sculpt Geometry Tool.
 How the density of isoparametric lines affects the surface detail possible when sculpting.
 How to increase the surface subdivisions on a NURBS surface to aid with surface sculpting.
 How to change the brush radius for the Sculpt Geometry Tool.
 How Opacity and Max Displacement affect the sculpting operations.
 How to import geometry from a pre-existing file into your current scene.