2011

and off or to turn off all snapping and tracking. See the keyboard illustration
in
Override Object Snap Settings on page 418.
Object snap tracking works in conjunction with object snaps. You must set
an object snap before you can track from an object's snap point.
Object Snap Tracking
Use object snap tracking to track along alignment paths that are based on
object snap points. Acquired points display a small plus sign (+), and you can
acquire up to seven tracking points at a time. After you acquire a point,
horizontal, vertical, or polar alignment paths relative to the point are displayed
as you move the cursor over their drawing paths. For example, you can select
a point along a path based on an object endpoint or midpoint or an
intersection between objects.
NOTE You can track Perpendicular or Tangent object snap from the last picked
point in a command even if the object snap tracking is off.
In the following illustration, the Endpoint object snap is on. You start a line
by clicking its start point (1), move the cursor over another line's endpoint
(2) to acquire it, and then move the cursor along the horizontal alignment
path to locate the endpoint you want for the line you are drawing (3).
Change Object Snap Tracking Settings
By default, object snap tracking is set to orthogonal. Alignment paths are
displayed at 0, 90, 180, and 270 degrees from acquired object points. However,
you can use polar tracking angles instead.
For object snap tracking, object points are automatically acquired. However,
you can choose to acquire points only when you press Shift.
Change Alignment Path Display
You can change how AutoTrack displays alignment paths, and you can change
how object points are acquired for object snap tracking. By default, alignment
paths stretch to the end of the drawing window. You can change their display
to abbreviated lengths, or no length.
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