Datasheet

ALTERNATIVE TO PEDIT
You can create regions with the BOUNDARY command or with the REGION command.
Either way, you can also use regions to create complex objects quickly by using the
SUBTRACT, INTERSECT, and UNION commands. The shape shown in Figure 1.9 was
created in under one minute (actually, 38 seconds).
To create regions from existing closed plines or circles, use the REGION command and
select the objects. You can create a new object using SUBTRACT, UNION, or INTERSECT,
and that object is also a region. If you need to work with individual lines or arcs, use the
EXPLODE command to break the region into entities.
Drawings with Interior Angles
For many drawings, you know the length of each line and the angles between lines. How-
ever, you probably don’t know the absolute angle of each line in the X-Y plane (angle
from 0°–East). There is a strategy for doing drawings of this kind; it involves recognizing
that supplemental angles form a straight line (180°). It also involves using the often-
overlooked Relative option of AutoCAD’s polar tracking feature.
To set polar tracking to Relative, right-click the POLAR button at the bottom of the
screen, and select Settings. Select the Relative To Last Segment radio button in the Polar
Tracking tab of the Drafting Settings dialog box. Select the Track Using All Polar Angle
Settings option as well, as shown in Figure 1.10.
Figure 1.9
New shapes
from regions
If you have trouble understanding what a region is, think of it as a flat 3D object with a thick-
ness of 0. The 3D Boolean editing commands will work with any region; the REGION com-
mand can be useful for other applications as well, including creating floating viewports in
a layout.
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