Getting Familiar with Paths in Adobe Flash CS4 Professional
Before the introduction of Flash, most popular graphics programs were designed to create and edit bitmap graphics. Flash was one of the first popular programs to rely primarily on vector graphics instead of bitmaps. One of the innovations in Flash was a new set of tools that made creating vector graphics as simple and intuitive as creating bitmap graphics.
Since then, other programs such as Adobe Illustrator have further simplified the process of making vector graphics, but their tools often work differently from those in Flash. You need to become familiar with the unique ways in which Flash handles vector graphics.
The most basic element of a vector drawing is a path. A path can be defined as a series of anchor points connected by either straight lines or curves. Think of the anchor points as a skeleton that gives the path its structure; and think of the connecting lines or curves as skin stretched over the skeleton.
Paths can be open or closed. An open path has a beginning and end, marked by anchor points known as endpoints. A closed path completely encloses an area; it has no beginning and no end (see Figure 1). You create paths by using drawing tools such as the Pen tool, the Pencil tool, and the Brush tool, all of which you'll learn about later in this chapter.
To do anything to an existing path—such as edit, move, or delete it—you must tell Flash which path you want to work with by selecting it with a tool. The two most important such tools are the Selection tool, represented by a black arrow, and the Subselection tool, represented by a white arrow (see Figure 2).
To use these tools, click the item you wish to select. The fundamental difference between them is that the Selection tool is used to select an entire path, while the Subselection tool is used for individual anchor points within a path. A selected anchor point is represented by a filled-in circle; an unselected anchor point is represented by a hollow circle (see Figure 3).
One of the innovations in Flash was allowing a user to work with vector paths without always having to pay attention to anchor points. For example, if you wanted to change a straight line into a curve in a traditional vector drawing program, you'd have to select the anchor points at each end of the curve and manipulate them. (You can still do this in Flash if you want to; I show you how in my book.) In Flash, however, you can turn a line into a curve simply by dragging a portion of the line outward with the Selection tool.
To do this, position the pointer anywhere between two anchor points. A small curve appears next to the pointer, alerting you that dragging from this point will reshape the line or curve (see Figure 4).
If you position the Selection tool over an anchor point, a small right angle appears next to the pointer (see Figure 5). This alerts you that dragging from this location will change the position of the anchor point itself, rather than reshaping the line or curve that connects two anchor points.
To use either of these techniques, you have to make sure the path that you want to edit isn't currently selected. (To deselect a selected path, click somewhere outside it with the Selection tool.)