Adobe Illustrator CS4 User Manual
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USING ADOBE ILLUSTRATOR CS4
Drawing
A smooth point always has two direction lines, which move together as a single, straight unit. When you move a
direction line on a smooth point, the curved segments on both sides of the point are adjusted simultaneously,
maintaining a continuous curve at that anchor point.
In comparison, a corner point can have two, one, or no direction lines, depending on whether it joins two, one, or no
curved segments, respectively. Corner point direction lines maintain the corner by using different angles. When you
move a direction line on a corner point, only the curve on the same side of the point as that direction line is adjusted.
Adjusting direction lines on a smooth point (left) and a corner
point (right)
Direction lines are always tangent to (perpendicular to the radius of) the curve at the anchor points. The angle of each
direction line determines the slope of the curve, and the length of each direction line determines the height, or depth,
of the curve.
Moving and resizing direction lines changes the slope of curves.
Note: In Illustrator, you can show or hide anchor points, direction lines, and direction points by choosing View
> Show
Edges or View
> Hide Edges.
Specify direction line and direction point appearance
When working with anchor points and paths, you may sometimes need to see direction lines (handles), while at other
times they may get in the way. You can show or hide direction lines for multiple selected anchor points. For a single
anchor point, the lines always appear.
You can choose to show or hide direction lines on a per-selection basis, or you can set a preference for direction line
display.
For a video on setting direction lines and points, see
See also
Show or hide direction lines for selected anchor points
1
Use the Direct Selection tool to select the desired anchor points.