Drawing Lines with the Pen Tool | Adobe InDesign CS3 Bible

The Pen tool is very versatile. With it you can create lines ( open paths) and shapes (closed paths).

Straight and zigzag lines

The simplest kind of path is a straight line (that is, an open path ) with a single segment, which you can create with either the Line tool or the Pen tool. But the Pen is much mightier than the Line, because it lets you draw zigzag lines with multiple straight segments, curvy lines, and lines that contain straight and curved segments. You can't draw those kinds of shapes with the Line tool, or any of the other object-creation tools, for that matter.

Cross-Reference ‚

Chapter 10 covers the Line tool.

To draw lines with straight segments:

Select the Pen tool or press P if the Type tool isn't selected.
Move the Pen pointer to where you want to place one of your line's endpoints, then click and release the mouse button (make sure you don't drag before you release the mouse button).

When you click and release the mouse button while using the Pen tool, you create a corner point. A small, filled-in square indicates the anchor point, which is also an endpoint of the open shape you're creating.
Move the Pen pointer to where you want to place the next anchor point, then click and release the mouse button.

When you create the second point, a straight line connects it with the first point, the first anchor point changes to a hollow square, and the second anchor point is filled in. (If you want to create a line with a single segment, you can stop drawing at this point by choosing another tool.)
For each additional anchor point, move the Pen pointer, then click and release the mouse button.

If you hold down the Shift key as you click, the angles you create are limited to multiples of 45 degrees. To reposition an anchor point after you click the mouse button but before you release it, hold down the spacebar and drag. (Be careful: If you drag before you press the spacebar, you'll create a smooth point and curved segments.)
To complete the path, hold down the z key or the Ctrl key and click on an empty portion of the page or choose another tool.

If you click on the page, the Pen tool remains selected and you can continue creating additional paths. Figure 26-8 shows a path in various stages of being drawn.

Figure 26-8: As each anchor point was created (from left to_right), a new, straight segment was added to the path. The finished open path is a zigzag line that contains four straight segments produced by clicking and releasing the mouse a total of five times.

You can also complete the path by clicking on the first point you created, but if you do, you'll create a closed path (closed paths are covered in the next section).

Tip ‚

As you create a path, you can move any anchor point, direction line handle, or the entire path by holding down the z or Ctrl key, then clicking and dragging whatever element you want to move.

Curved lines

If all you ever need to create are zigzag lines with corner points and straight segments, the click-and-release method in the preceding section is all you need to know. But if you want to create curvy lines, you need to take the next step up the B ƒ zier ladder and learn to add smooth points. Creating smooth points and curved segments is much like creating corner points and straight segments ‚ with a twist. There are two ways of connecting curved segments when drawing a path: with smooth points and with corner points. Both methods are explained in the steps that follow.

Curved segments connected by smooth points

If you want to draw a continuously curvy path that contains no corner points and no straight segments, you should create only smooth points as you draw. Here's how:

Select the Pen tool or press P if the Type tool isn't selected.
Move the Pen pointer to where you want to place one of your line's endpoints, then click and hold down the mouse button.

The arrowhead pointer is displayed.
Drag the mouse button in the direction of the next point you intend to create.

(Adobe suggests dragging about one-third of the way to the next point.) As you drag, the anchor point, its direction line, and the direction line's two handles are displayed, as shown in Figure 26-9. If you hold down the Shift key as you drag, the angle of the direction line is limited to increments of 45 degrees.

Figure 26-9: To create a smooth point when beginning a path, click and hold the mouse and drag in the direction of the next point. Here you see the direction line of a smooth endpoint created by clicking and dragging in the direction of the next anchor point.
Release the mouse button.
Move the Pen pointer where you want to establish the next anchor point ‚ and end the first segment ‚ then drag the mouse.

If you drag in approximately the same direction as the direction line of the previous point, you'll create an S-shaped curve; if you drag in the opposite direction, you'll create a C-shaped curve. Figure 26-10 shows both kinds of curves.

Figure 26-10: A C-shaped curved segment (left); an S-shaped curved segment (right).
When the curve between the two anchor points looks how you want it to look, release the mouse button.
Continue moving the Pen pointer, clicking, dragging, then releasing the mouse button to establish additional smooth points and curved segments.
To complete the path, hold down the z key or the Ctrl key and click on an empty portion of the page or choose another tool.

If you click on the page, the Pen tool remains selected and you can continue creating additional paths.

You can also complete the path by clicking on the first point you created, but if you do, you'll create a closed path (closed paths are covered in the next section). Figure 26-11 shows a finished line that contains several curved segments.

Figure 26-11: This line contains five anchor points ‚ all smooth points ‚ and four curved segments. The two segments on the left are both C-shaped curves; the two on the right are S-shaped.

Tip ‚

The two segments that form a smooth point's direction line work together as a single, straight line. When you move a handle, the line acts like a teeter -totter; the opposite handle moves in the opposite direction. If you shorten one of the segments, the length of the other segment doesn't change. The angle and length of direction lines determine the shape of the segments with which they're associated.

Curved segments connected by corner points

Sometimes you may need to create a line with curvy segments that don't adjoin smoothly. Figure 26-12 shows an example of a line that's made up of several C-shaped curves that are connected with corner points. When adjoining segments ‚ curved or straight ‚ meet at a corner point, the transition is abrupt rather than smooth, as it is at a smooth point. To create this kind of shape, you need to be able to connect curved segments using corner points instead of smooth points. Here's how:

Select the Pen tool or press P if the Type tool isn't selected.
Move the Pen pointer to where you want to place one of your line's endpoints, then click and hold down the mouse button.

The arrowhead pointer is displayed.
Drag the mouse button in the direction of the next point you intend to create.

As you drag, the anchor point, its direction line, and the direction line's two handles are displayed. If you hold down the Shift key as you drag, the angle of the direction line is limited to increments of 45 degrees.
Move the Pen pointer to where you want to establish the next anchor point ‚ and end the first segment ‚ then press Option or Alt and drag the mouse.

As you drag, the anchor point's handle moves and the direction line changes from a straight line to two independent segments. The angle of the direction line segment that you create when you drag the handle determines the slope of the next segment.
Release the mouse button.
Continue moving the Pen pointer and repeat Step 4 and Step 5 to create additional segments joined by corner points.
To complete the path, hold down the z key or the Ctrl key and click on an empty portion of the page or choose another tool.

If you click on the page, the Pen tool remains selected and you can continue creating additional paths.

Figure 26-12: Here, three corner points join four curved segments. The direction handles of the two rightmost segments are visible. The direction handles of a corner point are joined like a hinge; moving one handle doesn't affect the other handle.

Figure 26-12 shows a line with several curved segments joined by corner points.

Note ‚

A corner point that connects two curved segments has two direction lines; a corner point that connects two straight segments has no direction lines; and a corner point that connects a straight and curved segment has one direction line. If you drag a corner point's direction line, the other direction line, if there is one, is not affected. The angle and length of direction lines determine the shape of the segments with which they're associated.

Combining straight and curved segments

By combining the techniques for drawing straight segments and curved segments, you can create lines that contain both. Figure 26-13 shows three lines made up of straight and curved segments, as well as curved segments joined by smooth points and curved segments joined by corner points.

Figure 26-13: Three paths with both curved and straight segments, as well as corner points and smooth points.

Here's how to draw a straight segment followed by a curved segment:

While drawing a path, create a straight segment by clicking and releasing the mouse button, moving the Pen pointer, then clicking and releasing the mouse button again.
Move the Pen pointer over the last anchor point you created in Step 1.

The Convert Point icon (insert icon) is displayed.
Click, drag, and then release the mouse button to create the direction line that determines the slope of the next segment.
Move the Pen pointer to where you want to establish the next anchor point, then click and drag to complete the curved segment.

Figure 26-14 shows a step-by-step sequence of a curved segment being added to a straight segment. You can also follow a straight segment with a curved segment by simply clicking and dragging to create a smooth point. However, if you don't use the method explained in the earlier steps, you'll be able to adjust the slope associated with only one of the curved segment's anchor points rather than both.

Figure 26-14: At left is a straight segment. In the center, one of the direction lines of the straight segment's endpoint is being dragged. At right, clicking and dragging create a smooth anchor point, and a C-shaped curve is added after the straight segment.

To draw a curved segment followed by a straight segment:

While drawing a path, create a curved segment by clicking, dragging, then releasing the mouse button, and then moving the Pen pointer, clicking, dragging, and releasing the mouse button again.
Move the Pen pointer over the last anchor point you created in Step 1.

The Convert Point icon (insert icon) is displayed.
Click on the anchor point to convert it from a smooth point to a corner point.
Move the Pen pointer to where you want to establish the next anchor point, then click and release the mouse button to complete the straight segment.

Figure 26-15 shows a straight segment being added to a curved segment.

Figure 26-15: At left is a curved segment. In the center, the curved segment's smooth endpoint has been changed to a corner point. At right, clicking and releasing the mouse creates a new corner anchor point, and a straight segment is added to the curved segment.

Tip ‚

When creating paths, you should use as few anchor points as possible. As you become more comfortable creating free-form paths, you should find yourself using fewer anchor points to create paths.