Chapter 4 CAD Commands and Functions 105
lines are required. The
Double Line
command
is especially useful in architectural drafting for
drawing walls on a floor plan, fl Figure 4-4. Most
CAD programs allow you to set the distance
between the double lines. In addition, some
programs allow you to control how the corners
and intersections are formed.
AutoCAD Example:
Command: mline↵
Current settings: Justifi cation = Top, Scale = 1.00,
Style = STANDARD
Specify start point or [Justification/Scale/STyle]: 0,0↵
(or pick a point on screen)
Specify next point: 6,0↵
(or pick a point on screen)
Specify next point or [Undo]: 6,4↵
(or pick a point on
screen)
Specify next point or [Close/Undo]: 3,4↵
(or pick a
point on screen)
Specify next point or [Close/Undo]: 3,5↵
(or pick a
point on screen)
Specify next point or [Close/Undo]: 0,5↵
(or pick a
point on screen)
Specify next point or [Close/Undo]: close↵
(or pick a
point on screen)
Command:
Point
Points define exact coordinate locations. fi
In addition to serving as coordinates for lines
and other entities, points can also be created
as objects in most CAD programs. Points are
helpful as a reference for making constructions
and placing other objects. They can typically be
created with the
Point
command. After entering
the command, you can enter coordinates or pick
a location on screen.
Most CAD programs provide different vis-
ibility modes for displaying points on screen.
For example, you can display points as small
crosses or boxes.
AutoCAD Example:
Command: point↵
Current point modes: PDMODE = 0 PDSIZE = 0.0000
Specify a point: 3,0↵
(or pick a point on screen)
Command:
Circle
The
Circle
command automates the creation
of a circle object. Instead of drawing several
small straight-line segments to approximate a
circle, this command draws an object based on
the mathematical defi of a circle, finition Figure 4-5.
Most CAD software allows you to select from
several common methods of defining a circle. fi
These methods include:
• Center and radius.
• Center and diameter.
• Three points on the circle.
• Two points on the circle.
• Radius and two lines or two circles to
which the circle should be tangent.
AutoCAD Example:
Command: circle↵
Specify center point for circle or [3P/2P/Ttr (tan tan
radius)]: 0,0↵
(or pick a center point on screen)
Specify radius of circle or [Diameter]: diameter↵r r
Specify diameter of circle: 4↵
(or pick a point on the
circle on screen)
Command:
Figure 4-4. A double line can be used to quickly
create walls.
Figure 4-5. There are several ways to defi ne a circle.