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How to Draw and Edit Paths

Photoshop's path tools provide the most flexible and precise ways to define a selection short of masking. However, while a godsend to the experienced user, the path tools represent something of a chore to novices and intermediates. Most people take some time to grow comfortable with the pen tool, for example, because it requires you to draw a selection outline one point at a time.

The following pages get you up and running with all the path features. I explain how to draw a path, edit it, convert it to a selection outline, and stroke it with a paint or edit tool. All in all, you learn more about paths than you ever wanted to know.

Paths overview

You create and edit paths from scratch by using the various pen tools or shape tools. (Figure 8-2, earlier in this chapter, shows all the path-related tools along with their selection tool counterparts.) Path management options — which enable you to convert paths to selections, fill and stroke paths, and save and delete them — reside in the Paths palette, shown in Figure 8-24.

Figure 8-24: To save and organize your paths, display the Paths palette by choosing Window Paths.

How paths work

Paths differ from normal selections because they exist on the equivalent of a distinct, object-oriented layer that sits in front of the bitmapped image. This setup enables you to edit a path with point-by-point precision with no fear that you'll accidentally mess up the image, as you can when you edit ordinary selection outlines. After you get a path just so, you convert it to a standard selection outline, which you can then use to edit the contents of the image. (I detail this part of the process in the section "Converting and saving paths" later in this chapter.)

The following steps explain the basic process of drawing a selection outline with the path tools. I explain each step in more detail throughout the remainder of this chapter.

STEPS: Creating a Selection with the Path Tools

Draw the path. Make sure the Paths button is selected in the Options bar, and then use a pen tool or a shape tool to draw the outline of your prospective selection.

Edit the path. If the path requires some adjustment, reshape it using the other path tools.

Save the path. When you get the path exactly as you want it, save the path by choosing the Save Path command from the Paths palette menu. Or double-click the Work Path item in the scrolling list.

Convert the path to a selection. You can make the path a selection outline by choosing the Make Selection command or by pressing Enter on the numeric keypad when a path or selection tool is active.

That's it. After you convert the path to a selection, it works like any of the selection outlines described earlier. You can feather a selection, move it, copy it, clone it, or apply one of the special effects described in future chapters. The path remains intact in case you want to do further editing or use it again.

Sorting through the path tools

Before I get into my long-winded description of how you draw and edit paths, here's a quick introduction to the path tools. First up, the tools on the pen tool flyout:

Pen: Use the pen tool to draw paths in Photoshop one point at a time. Click to create a corner in a path; drag to make a smooth point that results in a continuous arc. (Never fear, I explain this tool ad nauseam in the "Drawing paths with the pen tool" section later in this chapter.) You can select the pen tool by pressing P; press P again to toggle to the freeform pen, described next. (As always, the shortcuts assume that you turned off the Use Shift Key for Tool Switch option in the Preferences dialog box.)

Freeform pen: Drag with this tool to create a path that automatically follows the twists and turns of your drag. Simplicity at its best; control at its lowest. Luckily, you can turn around and edit the path after you initially draw it.

The magnetic pen, doesn't actually appear in the toolbox. But if you select the freeform pen and then select the Magnetic check box in the Options bar, the freeform pen dashes into a phone booth and becomes the magnetic pen. Click the edge of the foreground element you want to select and then move the cursor along the edge of the shape. Photoshop automatically assigns points as it deems appropriate.

Add anchor point: Click an existing path to add a point to it.

Delete anchor point: Click an existing point in a path to delete the point without creating a break in the path's outline.

Convert point: Click or drag a point to convert it to a corner or smooth point. You also can drag a handle to convert the point. To access the convert point tool, press Alt (Win) or Option (Mac) when the pen is active. Press Ctrl+Alt (z -Option on the Mac) when an arrow tool (explained in the next section) is active. (The terms anchor point, smooth point, and others associated with drawing paths are explained in the upcoming section.)

You can use the pen tool to add, delete, and convert points, too, providing that you turn on the Auto Add/Delete check box in the Options bar. Pass the cursor over a segment in a selected path to toggle to the add anchor point tool; move the cursor over a point to get the delete anchor point tool. Press Alt (Option on the Mac) over a point to get the convert point tool.

If all you need is a simple, geometric path, you can save time by creating the path with the shape tools. I cover these tools in detail in Chapter 14, so I won't repeat everything here. Just know that after you select a shape tool, you shift it into path-drawing mode by clicking the Paths button in the Options bar, labeled in Figure 8-25. (The pen that appears on the button face serves as a reminder that you're in path country.) Photoshop sets the shape tools to that mode automatically if you select them while working on an existing path.

Figure 8-25: Click the Paths button in the Options bar to draw paths with the shape tools.

As you draw, Photoshop automatically adds whatever points are needed. You only need to worry about selecting a path overlap button, which determines how paths intersect and interact. See the next section to find out which button to choose when.

After you create a path, you can select it or edit it by using the two tools on the flyout directly above the pen tools flyout:

Path selection tool (black arrow): This tool selects an entire path. Just click inside the path to select it. If you created subpaths, the tool selects only the one under your cursor. You also use this tool to select vector objects, as explained in Chapter 14.

Direct selection tool (white arrow): This tool permits you to drag points and handles to reshape a path. You can access the tool when any other path tool is active by pressing and holding Ctrl (z on the Mac). And you can Alt-click (Option-click on the Mac) inside a path to select the entire path without switching to the path selection (black arrow) tool.

You can access the arrow tools from the keyboard by pressing A. You know the drill: Press A to switch to the tool that's currently active; press A again to toggle to the other tool. (Add Shift if you turned on the Use Shift Key for Tool Switch option in the Preferences dialog box.)

Drawing paths with the pen tool

When drawing with the regular pen tool, you build a path by creating individual points. Photoshop automatically connects the points with segments, which are simply straight or curved lines.

All paths in Photoshop are Bzier (pronounced bay-zee-ay) paths, meaning they rely on the same mathematical curve definitions that make up the core of the PostScript printer language. The Bzier curve model allows for zero, one, or two levers to be associated with each point in a path. These levers, labeled in Figure 8-26, are called Bzier control handles or simply handles. You can move each handle in relation to a point, enabling you to bend and tug at a curved segment like it's a piece of soft wire.

Figure 8-26: Drag with the pen tool to create a smooth point flanked by two Bzier control handles.

The following list summarizes how you can use the pen tool to build paths in Photoshop:

Adding segments: To build a path, create one point after another until the path is the desired length and shape. Photoshop automatically draws a segment between each new point and its predecessor. (The next section gets specific about how you use the tool to create points.)

Closing the path: If you plan to convert the path to a selection outline, you need to complete the outline by clicking again on the first point in the path. Every point will then have one segment entering it and another segment exiting it. Such a path is called a closed path because it completely encloses the desired area.

Leaving the path open: If you plan to apply the Stroke Path command (explained later), you may not want to close a path. To leave the path open, so it has a specific beginning and ending, deactivate the path by saving it (choose the Save Path command from the Paths palette menu).

Extending an open path: To reactivate an open path, click or drag one of its endpoints. Photoshop draws a segment between the endpoint and the next point you create.

Joining two open subpaths: To join one open subpath with another, click or drag an endpoint in the first subpath and then click or drag an endpoint in the second.

Specifying path overlap: You can set the path tools to one of four settings, which control how Photoshop treats overlapping areas in a path when you convert the path to a selection.

To make your will known, click one of the buttons near the right end of the Options bar, labeled in Figure 8-27. The button you click remains in effect until you choose another button.

Figure 8-27: Click one of these buttons in the Options bar to control how Photoshop treats overlapping areas when you convert a path to a selection.

Add to path area: Select this button if you want all areas, overlapping or not, to be selected.

Subtract from path area: Select this button to draw a subpath that eats a hole in an existing path. Any areas that you enclose with the subpath are not selected. Note that if you select a path and the Make Selection command is dimmed in the Paths palette, it's probably because you drew the path with the subtract option in force.

Intersect path areas: The opposite of Exclude, this option selects only overlapping areas.

Exclude overlapping path areas: Any overlapping regions are not included in the selection.

You can change the overlap setting for a subpath after you draw it if necessary. Select the paths with the black arrow tool and then click the overlap button for the setting you want to use.

Deactivating paths: At any time, you can press Enter or Return to dismiss — deactivate — the path. When you do, Photoshop hides the path from view. To retrieve the path, click its name in the Paths palette. Be careful with this one, though: If you dismiss an unsaved path and then start drawing a new path, you can lose the dismissed one. For more details, see "Converting and saving paths," later in this chapter.

Hiding paths: If you merely want to hide paths from view, press Ctrl+H (z -H on the Mac), which hides selections, guides, and other screen elements as well. You can also press Ctrl+Shift+H (z -Shift-H on the Mac) or choose View Show Target Path to toggle the path display on and off. To select which items you want to hide with Ctrl+H (Win) or z -H (Mac), choose View Show Show Extras Options.

To get a better sense of how the pen tool works, click the arrow button at the right end of the row of path-drawing icons to access the Pen Options (or "Option," in this case). Here you can enable the Rubber Band check box. This tells Photoshop to draw an animated segment between the last point drawn and the cursor. Unless you're an old pro and the connecting segment gets in your face, there's no reason not to select Rubber Band. (Besides, what with the '70s being so hot with the teenies, the Rubber Band check box makes the pen tool seem, well, kind of funky. Consider it another chance to bond with today's youth.)

The anatomy of points and segments

Points in a Bzier path act as little road signs. Each point steers the path by specifying how a segment enters it and how another segment exits it. You specify the identity of each little road sign by clicking, dragging, or Alt-dragging (Option-dragging on the Mac) with the pen tool. The following items explain the specific kinds of points and segments you can create in Photoshop. See Figure 8-28 for examples.

Figure 8-28: The different kinds of points and segments you can draw with the pen tool.

Corner point: Click with the pen tool to create a corner point, which represents the corner between two straight segments in a path.

Straight segment: Click at two different locations to create a straight segment between two corner points. Shift-click to draw a 45-degree-angle segment between the new corner point and its predecessor.

Smooth point: Drag to create a smooth point with two symmetrical Bzier control handles. A smooth point ensures that one segment meets with another in a continuous arc.

Curved segment: Drag at two different locations to create a curved segment between two smooth points.

Straight segment followed by curved: After drawing a straight segment, drag from the corner point you just created to add a Bzier control handle. Then drag again at a different location to append a curved segment to the end of the straight segment.

Curved segment followed by straight: After drawing a curved segment, Alt-click (Option-click on the Mac) the smooth point you just created to delete the forward Bzier control handle. This converts the smooth point to a corner point with one handle. Then click at a different location to append a straight segment to the end of the curved segment.

Cusp point: After drawing a curved segment, Alt-drag (Option-drag on the Mac) from the smooth point you just created to redirect the forward Bzier control handle, converting the smooth point to a corner point with two independent handles, sometimes known as a cusp point. Then drag again at a new location to append a curved segment that proceeds in a different direction than the previous curved segment.

Going freeform

If the pen tool is too much work, try the freeform pen tool, which is just a press of the P key away from the standard pen. As you drag, Photoshop tracks the motion of the cursor with a continuous line. After you release the mouse button, the program automatically assigns and positions the points and segments needed to create the Bzier path.

Alas, automation is rarely perfect. (If it were, what need would these machines have for us?) When the program finishes its calculations, a path may appear riddled with far too many points or equipped with too few.

Fortunately, you can adjust the performance of the freeform pen to accommodate your personal drawing style using the Curve Fit control, which you can access by clicking the arrow at the end of the row of path-drawing tool icons in the Options bar. You can enter any value between 0.5 and 10, which Photoshop interprets in screen pixels. The default value of 2, for example, instructs the program to ignore any jags in your mouse movements that do not exceed 2 pixels in length or width. Setting the value to 0.5 makes the freeform pen extremely sensitive; setting the value to 10 smoothes the roughest of gestures.

A Curve Fit from 2 to 4 is generally adequate for most folks, but you should experiment to determine the best setting. Like the magic wand's Tolerance setting, you can't alter the Curve Fit value for a path after you've drawn it. Photoshop calculates the points for a path only once, after you release the mouse button.

Going magnetic

To use the magnetic pen tool, first select the freeform pen tool and then select the Magnetic check box in the Options bar. The magnetic pen works like a combination of the magnetic lasso and the freeform pen. As with the magnetic lasso, you begin by clicking anywhere along the edge of the image element you want to select. (For a pertinent blast from the past, see Figure 8-5.) Then move the cursor — no need to drag — around the perimeter of the element and watch Photoshop do its work. To set an anchor point, click. When you come full circle, click the point where you started to complete the path.

You can create straight segments by Alt-clicking (Option-clicking on the Mac), just as you can when using the freeform pen without Magnetic turned on. And the Curve Fit option (in the Freeform Pen Options drop-down palette shown in Modifying the magnetic lasso options," near the beginning of this chapter, for complete information.

Figure 8-29: While the freeform pen is active, select the Magnetic check box in the Options bar to access the magnetic pen. Click the arrow at the left of the check box to display additional options.

Editing paths

If you take time to master the default pen tool, you'll find yourself drawing accurate paths more and more frequently. But you'll never get it right 100 percent of the time — or even 50 percent of the time. And when you rely on the freeform or magnetic pen tools, the results are never dead on. From your first timid steps until you develop into a seasoned pro, you'll rely heavily on Photoshop's capability to reshape paths by moving points and handles, adding and deleting points, and converting points to change the curvature of segments. So don't worry too much if your path looks like an erratic stitch on the forehead of Frankenstein's monster. The path-editing tools provide all the second chances you'll ever need.

Reshaping paths

The white arrow tool — known in official Adobe circles as the direct selection tool — represents the foremost path-reshaping function in Photoshop. To select this tool from the keyboard, first press A to select the black arrow tool and then press A again to toggle to the white arrow. Or just Alt-click (Win) or Option-click (Mac) the black arrow tool in the toolbox. (You use the black arrow to select, relocate, and duplicate entire paths or subpaths, as explained in the upcoming section "Moving and cloning paths.")

However you put your hands on the white arrow, you can perform any of the following functions with it:

Select points: Click a point to select it independently of other points in a path. Shift-click to select an additional point, even if the point belongs to a different subpath than other selected points. Alt-click (Win) or Option-click (Mac) a path to select all its points in one fell swoop. You can even marquee points by dragging a rectangle around them. You cannot, however, apply commands from the Select menu, such as All or Deselect, to the selection of paths.

Drag selected points: To move one or more points, select them and then drag one of the selected points. All selected points move the same distance and direction. When you move a point while a neighboring point remains stationary, the segment between the two points shrinks, stretches, and bends to accommodate the change in distance. Segments located between two selected or deselected points remain unchanged during a move.

Drag a straight segment: You also can reshape a path by dragging its segments. When you drag a straight segment, the two corner points on either side of the segment move as well. As illustrated in Figure 8-30, the neighboring segments stretch, shrink, or bend to accommodate the drag.

Figure 8-30: Drag a straight segment to move the segment and change the length, direction, and curvature of neigh- boring segments.

Drag a curved segment: When you drag a curved segment, you stretch, shrink, or bend that segment, as demonstrated in Figure 8-31.

Figure 8-31: Drag a curved segment to change the curvature of only that segment and leave the neighboring segments unchanged.

Drag a Bzier control handle: Select a point and drag either of its Bzier control handles to change the curvature of the corresponding segment without moving any of the points in the path. If the point is a smooth point, moving one handle moves both handles in the path. If you want to move a smooth handle independently of its partner, you must use the convert point tool, as discussed in the "Converting points" section later in this chapter.

Adding and deleting points and segments

The quantity of points and segments in a path is forever subject to change. Whether a path is closed or open, you can reshape it by adding and deleting points, which, in turn, forces the addition or deletion of a segment:

Appending a point to the end of an open path: If a path is open, you can activate one of its endpoints by clicking or dragging it with the pen tool, depending on the identity of the endpoint and whether you want the next segment to be straight or curved. Photoshop is then prepared to draw a segment between the endpoint and the next point you create.

Closing an open path: You also can use the technique I just described to close an open path. Select one endpoint, click or drag it with the pen tool to activate it, and then click or drag the opposite endpoint. Photoshop draws a segment between the two endpoints, closing the path and eliminating both endpoints by converting them to interior points, which simply means the points are bound on both sides by segments.

Joining two open subpaths: You can join two open subpaths to create one longer open path. To do so, activate an endpoint of the first subpath and then, using the pen tool, click or drag an endpoint of the second subpath.

Inserting a point in a segment: Using the add point tool, click anywhere along an open or closed path to insert a point and divide the segment into two segments. Photoshop automatically inserts a corner or smooth point, depending on its reading of the path. If the point does not exactly meet your needs, use the convert point tool to change it. In addition to using the add point tool, you can select the Auto Add/Delete check box in the Options bar. Then, whenever you pass the pen tool cursor over a segment, you see the little plus sign next to your cursor, indicating that the add point tool is temporarily in the house. This trick works only if the path is selected, however.

Deleting a point and breaking the path: The simplest way to delete a point and break the path is to select it with the white arrow and press Delete or Clear. (You also can choose Edit Clear, though why you would want to expend so much effort is beyond me.) When you delete an interior point, you delete both segments associated with that point, resulting in a break in the path. If you delete an endpoint from an open path, you delete the single segment associated with the point.

Removing a point without breaking the path: Select the delete point tool and click a point in an open or closed path to delete the point and draw a new segment between the two points that neighbor it. The delete point tool ensures that no break occurs in a path.

Deleting a segment: You can delete a single interior segment from a path without affecting any point. To do so, first click outside the path with the white arrow tool to deselect the path. Then click the segment you want to delete and press Delete. When you delete an interior segment, you create a break in your path.

Converting points

Photoshop lets you change the identity of an interior point. You can convert a corner point to a smooth point, and vice versa. You perform all point conversions using the convert point tool as follows:

Smooth to corner: Click an existing smooth point to convert it to a corner point with no Bzier control handle.

Smooth to cusp: Drag one of the handles of a smooth point to move it independently of the other, thus converting the smooth point to a cusp.

Corner to smooth: Drag from a corner point to convert it to a smooth point with two symmetrical Bzier control handles.

Cusp to smooth: Drag one of the handles of a cusp point to lock both handles back into alignment, thus converting the cusp to a smooth point.

Transforming paths

In addition to all the aforementioned path-altering techniques, you can scale, rotate, skew, and otherwise transform paths using the following techniques:

To transform all subpaths in a group — such as both the eye and skull outline in the first example of Figure 8-32 — select either arrow tool and click off a path to make sure all paths are deselected. Then choose Edit Free Transform Path.

Figure 8-32: To transform multiple paths at once (top), deselect all paths and press Ctrl+T (z -T on the Mac). Alternatively, you can transform independent paths or points by selecting them and pressing Ctrl+T (bottom).

To transform a single subpath independently of others in a group, click it with the black arrow and then select the Show Bounding Box check box in the Options bar. Or click the path with the white arrow and choose Edit Free Transform Path.

Photoshop even lets you transform some points independently of others inside a single path, as demonstrated in the second example of Figure 8-32. Just use the white arrow to select the points you want to modify and then choose Edit Free Transform Points.

In an attempt to conserve tree matter — which is being wasted liberally enough in this tome — I explain the larger topic of transformation in one central location, the "Applying Transformations" section of Chapter 12. Even so, here's a brief rundown of your transformation options after you press Ctrl+T (z -T on the Mac):

Scale: To scale a path, drag one of the eight square handles that adorn the transformation boundary. Alt-drag (Win) or Option-drag (Mac) a handle to scale with respect to the origin point. You can move the origin by dragging it or by clicking one of the boxes in the little bounding box icon at the left end of the Options bar.

Rotate: Drag outside the boundary to rotate the paths or points, as demonstrated in Figure 8-32.

Flip: Right-click (Control-click on the Mac) to access a pop-up menu of transformation options. Choose Flip Horizontal or Flip Vertical to create a mirror image of the path.

Skew: Ctrl-drag (Win) or z -drag (Mac) one of the side handles to slant the paths. Press Shift along with Ctrl or z to constrain the slant along a consistent axis.

Distort: Ctrl-drag (Win) or z -drag (Mac) one of the corner handles to distort the paths.

Perspective: Press Ctrl+Shift+Alt (z -Shift-Option on the Mac) and drag a corner handle to achieve a perspective effect.

Numerical transformations: If you need to transform a path by a very specific amount, use the controls in the Options bar, which are the same ones you get when transforming a regular selection. Modify the values as desired and press Enter or Return. (Figure 8-23 earlier in this chapter labels the options.)

When you finish stretching and distorting your paths, press Enter or Return or double-click inside the boundary to apply the transformation. You also can click the check-mark button at the right end of the Options bar. To undo the last transformation in the transform mode, press Ctrl+Z (z -Z on the Mac). Or bag the whole thing by pressing Escape.

Moving and cloning paths

You can relocate and duplicate paths as follows:

Clone a path: Click inside the path with the black arrow tool to select it. To select multiple subpaths, Shift-click them, or marquee-drag around them. Then Alt-drag (Option-drag on the Mac) to clone all selected paths.

Move a path: After selecting the path with the black arrow, drag the path to its new home.

Align and distribute paths: You can align two or more paths by selecting them with the black arrow and then clicking an alignment button in the Options bar. To space the paths evenly across the image, click one of the distribution buttons, which are shown in Figure 8-33. Press Enter or Return or click the check-mark button in the Options bar to apply the transformation.

Figure 8-33: You can align and distribute multiple selected paths, just as you can layers and vector objects.

Merging and deleting paths

When the black arrow is selected, the Options bar contains a Combine button (see Figure 8-33). Clicking this button merges all selected subpaths into one. When Photoshop combines the subpaths, it does so according to which path overlap options were active when you drew the subpaths. Remember, you can select a subpath with the black arrow to change its overlap setting if necessary. Just select the subpath and then click the appropriate overlap button in the Options bar (see Figure 8-33). Refer to the earlier section, "Drawing paths with the pen tool," for more information about overlap options.

To get rid of a path, click inside it with the black arrow or drag around it with the white arrow. Then press Delete. That path is outta here.

Filling paths

After you finish drawing a path, you can convert it to a selection outline — as described in the upcoming "Converting paths to selections" section — or you can paint it. You can paint the interior of the path by choosing the Fill Path command from the Paths palette menu, or you can paint the outline of the path by choosing Stroke Path. In either case, Photoshop applies the fill on the active image layer.

The Fill Path command works much like Edit Fill. After drawing a path, choose the Fill Path command or Alt-click (Option-click on the Mac) the fill path icon in the lower-left corner of the palette. (The icon looks like a filled circle.) Photoshop displays a slight variation of the Fill dialog box discussed in Chapter 6; the only difference is the inclusion of two Rendering options. Enter a value in the Feather Radius option box to blur the edges of the fill, as if the path were a selection with a feathered outline. Select the Anti-aliased check box to slightly soften the outline of the filled area. If you simply click the fill path icon without holding down a modifier key, the path is automatically filled with the foreground color.

When applying the fill, Photoshop adheres to the overlap option you used when creating the path. Suppose that you draw two round paths, one fully inside the other. If you drew both circles with the Add overlap option active, both circles get filled. If you drew the interior circle with the Invert option active, Photoshop fills only the area between the two paths, resulting in the letter O.

If the Fill Path command fills only part or none of the path, the path probably falls outside a selection outline. Choose Select Deselect or press Ctrl+D (z -D on the Mac) to deselect the image and then choose the Fill Path command again.

Painting along a path

Unlike the Fill Path command, which bears a strong resemblance to Edit Fill, the Stroke Path command is altogether different from Edit Stroke. Edit Stroke creates outlines on an active selection, whereas the Stroke Path command enables you to paint a brushstroke along the contours of a path. This may not sound like a big deal at first, but this feature enables you to combine the spontaneity of the paint and edit tools with the structure and precision of a path.

To paint a path, choose the Stroke Path command from the Paths palette menu to display the Stroke Path dialog box shown in Figure 8-34. In this dialog box, you can choose the paint or edit tool with which you want to stroke the path (which only means to paint a brushstroke along a path). Photoshop drags the chosen tool along the exact route of the path, retaining any tool or brush shape settings that were in force when you chose the tool.

Figure 8-34: Select the paint or edit tool that you want Photoshop to use to stroke the path.

The Stroke Path dialog box includes a Simulate Pressure check box, which is particularly useful for folks who don't have a pressure-sensitive tablet. Provided you use appropriate settings in the Brushes palette, this option begins your stroke with a thin line, fattens it up as it reaches the middle, and then tapers it off as it reaches the end. The effect is similar to what you could achieve with a pressure-sensitive drawing tablet. For experimentation, try these settings: Choose a large brush (around 20 pixels or so), turn on Shape Dynamics in the Brushes palette, set the first Control to Pen Pressure and the other Control options to Off, and set all the sliders as low as they will go. Now when you stroke your path, choose Brush as the tool, and turn on Simulate Pressure. Trs elegant, non?

The following steps walk you through a little project I created by stroking paths with the brush tool. Figures 8-35 through 8-39 show the progression and eventual outcome of the image.

STEPS: Stroking Paths with Paint Tools

After opening a high-resolution image of Saturn, I clicked the Paths button in the Options bar and drew the curvy path shown in Figure 8-35. As you can see, the path extends from the bottom of Saturn. I drew the path working downward, which is important to know because Photoshop strokes a path in the same direction as you draw the path.

Figure 8-35: I drew this path starting at the bottom of the planet and working my way downward.

I saved the path. I double-clicked the Work Path item in the Paths palette, entered a name for my path, and pressed Enter (or Return on the Mac).

I used the Brushes palette to create a custom brush. In the Brushes palette I selected the preset 59-pixel spatter brush, cranked the diameter up to 100 pixels, and then jumped over to Shape Dynamics and gave the brush high jitter settings. I Alt-clicked (Option-clicked on the Mac) on the stroke path icon at the bottom of the Paths palette, turned on Simulate Pressure, and let Photoshop stroke the path using a medium-gray color. The results are shown in Figure 8-36.

Figure 8-36: My path with a stroke applied. Turning on Simulate Pressure creates a tapered effect, similar to what you could achieve with a pressure-sensitive tablet.

I stroked the path three more times using the Stroke Path command. Repeating Step 3, I stroked the path again in dark gray, light gray, and white, using progressively smaller brush diameters (70, 45, and 20 pixels, respectively). The result of all this stroking is shown in Figure 8-37.

Figure 8-37: I stroked the path three more times, with diminishing brush sizes and different shades of gray.

Next, I drew three more paths. After drawing the first one, I double-clicked the new work path to save it, and then added two more paths to the one I just drew. I clicked in an empty portion of the image window with the black arrow tool to deselect all paths, so they appeared as shown in Figure 8-38. This enabled me to stroke them all simultaneously in Step 6.

Figure 8-38: I drew another path, saved it, and then repeated the process to add two more paths.

Using a 20-pixel brush, I stroked the three paths with black, reduced the brush diameter, and then stroked with medium gray. A little more path drawing, a little more pressure-simulated stroking, and the intergalactic advertising masterpiece shown in Figure 8-39 emerged. Pretty spectacular, huh? Beats some guy pounding the sidewalks wearing a sandwich board any day.

Figure 8-39: This should definitely increase Joe's alien clientele.

Converting and saving paths

Photoshop provides two commands to switch between paths and selections, both of which are located in the Paths palette menu. The Make Selection command converts a path to a selection outline; the Make Work Path command converts a selection to a path. Regardless of how you create a path, you can save it with the current image, which enables you not only to reuse the path, but also to hide and display it at will.

Converting paths to selections

When you choose the Make Selection command or Alt-click (Option-click on the Mac) the make selection icon (which looks like a dotted circle, as shown back in Manually adding and subtracting" section, earlier in this chapter.

Figure 8-40: When you choose the Make Selection command, you have the option of combining the path with an existing selection.

Photoshop offers several alternative ways to convert a path to a selection outline, all of which are more convenient than the Make Selection command:

Press Ctrl+Enter (Win) or z -Return (Mac): As long as a path, shape, or selection tool is active, this keyboard shortcut converts the path to a selection.

Ctrl-click (Win) or z -click (Mac) the path name: If a tool other than a path, shape, or selection tool is active, you can Ctrl-click (Win) or z -click (Mac) the name of a path in the Paths palette. The path needn't be active.

Ctrl+Shift+Enter or Ctrl+Shift-click (z -Shift-Return or z -Shift-click on the Mac): To add the path to an existing selection, press Shift with one of the previous techniques.

Alt+Enter or Ctrl+Alt-click (Option-Return or z -Option-click on the Mac): Naturally, if you can add, you can subtract.

Shift+Alt+Enter or Ctrl+Shift+Alt-click (Shift-Option-Return or z -Shift-Option-click on the Mac): Now we're starting to get into some obscure stuff, but what's possible is possible. You select the intersection of a path and a selection outline by pressing a whole mess of keys.

All these techniques offer the advantage of hiding the path when converting the path to a selection, giving you full, unobstructed access to your selection outline.

Converting selections to paths

You turn a selection into a path by choosing the Make Work Path command from the Paths palette. When you choose the command, Photoshop produces a dialog box containing a single option, Tolerance. Unlike the Tolerance options you've encountered so far, this one is accurate to 1/10 pixel and has nothing to do with colors or brightness values. Rather, it works like the Curve Fit option for the freeform pen and magnetic pen. That is, it permits you to specify Photoshop's sensitivity to twists and turns in a selection outline. The value you enter determines how far the path can vary from the original selection. The lowest possible value, 0.5, not only ensures that Photoshop retains every nuance of the selection, but also can result in overly complicated paths with an abundance of points. If you enter the highest value, 10, Photoshop rounds the path and uses few points. If you plan on editing the path, you probably won't want to venture any lower than 2.0, the default setting.

To bypass the Make Work Path dialog box and turn your selection into a path using the current Tolerance settings, click the make path icon at the bottom of the Paths palette. (It's labeled back in Figure 8-24.)

Saving paths with an image

As I mentioned at the beginning of the paths discussion, saving a path is an integral step in the path-creation process. You can store every path you draw and keep it handy in case you decide later to reselect an area. Because Photoshop defines paths as compact mathematical equations, they take up virtually no room when you save an image to disk.

You save one or more paths by choosing the Save Path command from the Paths palette menu or by simply double-clicking the italicized Work Path item in the scrolling list. After you perform the save operation, during which you name the path, the path name appears in nonitalicized characters in the palette.

A path listed in the palette can include any number of separate paths. In fact, if you save a path and then set about drawing another one, Photoshop automatically adds the new path in with the saved path. To start a new path under a new name, you first must hide the existing path. Or click the new path icon — the little page at the bottom of the Paths palette — to establish an independent path. To hide paths, you can click the empty portion of the scrolling list below the last saved path name. You can even hide unsaved paths in this way. If you hide an unsaved path and then begin drawing a new one, however, the unsaved path is deleted, never to return again.