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2 Chapter 10: Precision and Drawing Aids
Grids—
Include the home grid and special grid
objects. Both types of gr id can act as construc tion
planes. The software constructs objects using
the orientation and position of the ac tive grid.
While the home grid is fixed in world space, you
canrotategridobjectsandplacethemanywhere
in a scene, and align them to other objects and
surfaces. You can also give each grid object its
own spacing, and display any grid as a dedicated
viewport.
Object alignment—Matches an object w ith the
position,orientation,ornormalofanotherobject,
or to a point in space.
Object snaps —Ensure precise placement when
creating and rearranging objects. Keyboard
shortcuts let you change object snaps as you
work.Youcanalsosetsnapstofindgridlinesand
intersections. An angle snap sets the increment
for rotation, and a percent snap sets the increment
for scaling.
Helper s—Provide usef ul assistance, as the name
implies. These are specialized tools in the same
category as grid objects. A Tape object measures
distances in current units, and a Protractor
object measure angles. A Gr id object defines a
construct ion plane, and a Point object marks a
particular spot in 3D space.
How the Tools Work Together
The tools themselves establish a general order
of use and interaction, although you can always
change settings as needed w ithout following this
sequence.
• Choose a measur ing unit. The default is generic
units, sufficient for many purposes.
• Set grid spacing (the size of the smallest
square), based on the measuring unit. The
home gr id and grid objects can have their own
spacing, separate from the grid spacing.
• Moveandaligngridobjectstoauseful
orientation.
• Set or vary snap settings as needed in your
work.
•UseotherhelperobjectslikePointandTapeas
part of the precision process.
As you work, you can change your settings
(including t he measuring unit) without losi ng any
precision.
Helper s
Create panel > Helpers
Create menu > Helpers
Helper objects play a supporting role, like stage
hands or construc tion assistants.
Several categories of helpers are available f rom the
drop-down list on the Create panel:
Standard helpers (page 2–15)
Atmospher ic Apparatus (page 3–300)
Camera Match Helper (page 2–1235)
Assembly Head Help er Object (page 1–108)
• Character Assembly (page 2–681)
• Luminaire Helper Object (page 1–108)
ManipulatorHelperObjects(page2–26)
Particle Flow ( Speed By Icon Operator (page
2–158)
and Find Target Test (p age 2–214) )
VRML97 Helper Objects (page 3–646)
reactor
Other helper objects might be available, depending
on your configuration.