Saving Space and Time with Symbols

Sometimes, a project calls for a range of repeating design elements. For example, when creating a map of a park, you might use icons to indicate restrooms or picnic areas. And when designing an item of clothing, you might draw the same button in several different places. Illustrator has a feature that was created specifically to manage repeating graphics in a file, called symbols.

You can think of a symbol as a master art item, which is defined once per Illustrator document. Once created, you can place multiple instances of a symbol within a document. Each instance is simply an alias or a placeholder that points back to the original defined symbol. Using symbols in a document offers several benefits. First, if you edit or modify a symbol, all instances of that symbol are automatically updated as well. Second, because Illustrator only stores a single copy of a symbol per document, you can take advantage of smaller file sizes. Smaller file sizes translate to faster open and save times, faster print times, and faster server transfer times.

Designers who create certain kinds of Web graphics can also take advantage of using symbols. In Chapter 10, Illustrator and the Web, we'll discuss how symbols can be used to generate smaller file sizes when creating SWF (Flash) and SVG files.

Working with Symbols and Instances

Defining a symbol is quick and easy. Select any artwork on your artboard and drag it into the Symbols palette. Double-click a symbol in the Symbols palette to give it a unique name. Unlike brushes, which are limited in the kinds of artwork they can contain, you can use any kind of artwork to define a symbol with the exception of placed-linked images (for more information on linked images, see Chapter 8, Mixing It Up: Working with Vectors and Pixels). Objects with live effects applied, and even editable text, can be stored inside a symbol in Illustrator. Once you've defined a symbol in the Symbols palette, you can delete the artwork that you used to create it if you'd likea complete copy of the artwork is stored inside of the file.

Dragging a symbol from the Symbols palette out onto the artboard creates a symbol instance. Alternatively, you can select a symbol in the Symbols palette and click on the Place Symbol Instance icon to create a symbol instance at the center of the document (Figure 5.14). Once on the artboard, you'll notice that a symbol instance cannot be edited, even when you're using the Direct Selection tool. A symbol instance doesn't give you access to the actual artwork because it is simply a placeholder (Figure 5.15). However, you can use any of Illustrator's transformation tools and functions with symbol instances. For example, you can scale or rotate a symbol instance as necessary. Additionally, you can specify transparency features and even apply live effects to symbol instances. You can place as many symbol instances in a document as you desire and each instance can be scaled or transformed differently. You can copy and paste symbols between documents as well.

Figure 5.14. You can use the Place Symbol Instance icon to place symbols on the center of your screen.

Figure 5.15. Even though a symbol may be made up of vectors, you can't edit symbol instances on the artboard.

Pressing Command-Shift (Ctrl-Shift) while dragging artwork into the Symbols palette defines a symbol and at the same time turns the art on the artboard into a symbol instance.

Replacing Symbols

If you think about it, a symbol instance is really an empty box, which references real artwork that resides in the Symbols palette. With this fundamental understanding, it should be possible to take a symbol instance that references one symbol, and change it so that it references a different symbol that you've defined. In Illustrator, the ability to switch an instance to point to a different symbol is called replacing symbols.

Although you can't include linked images in a symbol, you can include embedded images. Because you can use symbols many times in a document with no adverse effect on file size, it makes sense to think about creating symbols from an embedded image if you need to use them often in a file.

To replace a symbol instance, select it on the artboard and then click the symbol in the Symbols palette that you want to replace it with. With both the symbol instance and the new symbol selected, click the Replace Symbol icon in the Symbols palette or choose Replace Symbol from the Symbols palette menu. The selected symbol instance updates accordingly. When replacing symbol instances, any transformations or effects that you've applied to any individual instances will remain intact.

Modifying Symbols and Instances

At any time, you can click the Break Link to Symbol icon in the Symbols palette to "expand" the instance. Doing so gives you access to the individual objects that were used to define the symbol (Figure 5.16). Once you've broken a link to a symbol, the artwork is no longer tied back to the symbol and any benefits of using symbols no longer apply to that art. Updating or modifying the symbol does not update the art.

Figure 5.16. Once a symbol instance has broken its link, the paths and objects are available to edit.

Modifying a symbol is much like modifying a swatch or a brush. Select both the new artwork on the artboard and the symbol in the Symbols palette that you want to modify. Hold the Option (Alt) key down and drag the artwork onto the symbol in the Symbols palette. When you do, a black border appears around the symbol indicating that you are about to modify it. Alternatively, you can select both the art and the symbol and choose Redefine Symbol from the Symbols palette.

When a symbol is redefined, all instances on the artboard that reference the symbol are updated to reflect the change. Any attributes or transformations that were applied to the instances are preserved.

When you redefine a symbol in one document, it does not update other files that may use the same symbol. The change is local to just the document that is open and being worked on.

Uses for Symbols

When you take a moment to think about your project before you start working on it, you might be able to determine whether using symbols would benefit you. Here is a list of several ways symbols can be used to help build better files:

• Although Illustrator's doesn't have master pages, symbols can act like miniature "master art elements" in a file. For example, when creating several different ideas for a packaging concept, use symbols as the base for each design, (i.e., ingredients, nutrition info, weight, etc.). Updating a symbol then instantly updates all of the design comps in the file at once.

• Create symbol libraries to store commonly used logos and icons. (Back in Chapter 1, The Illustrator Environment, you learned how to save and load libraries.)

• Create symbol libraries to store collections of fashion elements like buttons, zippers, or labels, or other specific art elements, like architectural elements or cartography symbols.

• The use of symbols is required in order to perform certain features in Illustrator, including the ability to create custom 3D bevels and artwork mapped onto the surfaces of 3D objects. This functionality is covered in Chapter 7, 3D and Other Live Effects.

Be sure to check out Ivan Torres's Symbols example in the color insert.

Of course, there are plenty of other ways you can use symbols in Illustrator. The next section deals with some special tools created specifically for working with symbols: the Symbolism tools.

Having Fun with the Symbolism Tools

So you've been reading along and totally get the benefits of using symbols where possible to create more efficient files. Say, for example, that you are going to create a night sky for an illustration and need to fill the sky with stars. So you create a symbol of a nice star with a cool glow effect and define it as a symbol. One by one, you drag out symbol instances and scale and rotate each star to achieve a more natural look (Figure 5.17). As you drag out yet another symbol instance, you think, there's got to be a better way to do this. The good news is, there is. The great news is, the better way is extremely fun!

Figure 5.17. Dragging out and editing individual symbol instances can be tedious.

In the Toolbox, you'll find the Symbol Sprayer tool. Hidden beneath it, you'll find seven more tools; together, these tools are referred to as the Symbolism tools (Figure 5.18). The reason for the name is that these tools all work using symbols, and not by any coincidence, the tools all begin with the letter "s" (See? Adobe actually does pay attention to detail).

Figure 5.18. The Symbolism tools all appear grouped in the Toolbox with the Symbol Sprayer tool.

Creating a Symbol Set

The Symbol Sprayer tool was created to easily add multiple symbol instances to a document. Choose the Symbol Sprayer tool from the Toolbox and then click any symbol in the Symbols palette. Because the Symbol Sprayer tool only works with symbols, it's important to first select a symbol to work withotherwise the Symbol Sprayer won't work. Click and drag on the artboard while holding the mouse button, and you'll begin to see the Symbol Sprayer adding symbols to your page (Figure 5.19). When you release the mouse button, a single outline appears around the perimeter of the symbols. What you have actually created is a symbol set, which is a collection of symbol instances (Figure 5.20). If you switch to the Selection tool, you'll find that you can't select the individual symbol instances, but you can move the entire symbol set as a whole.

Figure 5.19. As you click and drag with the Symbol Sprayer tool, instances appear to flow onto your artboard.

Figure 5.20. Once you release the mouse, the symbol instances appear united in a single symbol set.

Although it may seem silly that you can't select individual instances within a symbol set, that notion quickly changes when you realize that the Symbol Sprayer tool is interactive. Select the symbol set and switch back to the Symbol Sprayer tool. If you click and drag, the Symbol Sprayer tool adds more symbol instances to the set. If you press the Option (Alt) key while dragging, you remove symbols from the set. In addition, the Symbol Sprayer tool has support for pressure-sensitive tablets, so the harder you press, the faster the instances appear.

It's certainly fun to spray symbols all over your document, but there is a way that you can control the individual symbols that appear inside of a symbol set. To do this, you need to employ the Symbolism tools.

Using the Specialized Symbolism Tools

Once you've created a symbol set with the Symbol Sprayer tool, you can switch to any of the other Symbolism tools to adjust the symbols within the set. It's important to realize that symbol sets are intended to create a natural collection of symbol instances. You'll find that you can't position symbol instances precisely with the Symbolism tools. On the contrary, the Symbolism tools are meant to offer Illustrator users a more free-flowing style, and it almost feels as if you are suggesting a particular movement or behavior to symbol instances rather than performing a definitive action to them. As you try each of these tools, you'll get a better feel for how they function, and for how you might be able to use them for your projects.

You can add different symbols to the same symbol set. Once you've created a symbol set using one symbol, choose another symbol from the Symbols palette and add more symbols to your symbol set. You can add as many different kinds of symbols as you want to a symbol set.

For each of these tools, you'll notice that a circle appears, which indicates the diameter of the tool's area of influence (Figure 5.21). You can make this area larger or smaller by pressing the bracket keys ([/]) on your keyboard (similar to Photoshop's keyboard shortcut for changing brush size).

Figure 5.21. You can resize the circle area, which indicates the tool's area of influence, to be bigger or smaller.

• Symbol Shifter tool. The Symbol Shifter tool moves symbol instances around. Clicking and dragging this tool pushes symbols in the direction of your cursor (Figure 5.22). If you hold the Shift key while dragging, Illustrator brings the symbol instances from the back of the symbol set's stacking order to the front.

  Figure 5.22. The Symbol Shifter tool allows you to reposition the symbol instances within a symbol set.

  

  
  

  

  Although the Symbolism tools aren't meant to work on just one symbol instance at a time, you can make your area of influence small enough so that you can affect a much smaller area, or even individual symbols.

  
  
  
  

• Symbol Scruncher tool. The Symbol Scruncher tool moves symbol instances closer together, making the appearance more dense. Clicking and dragging with the Symbol Scruncher tool causes instances to become attracted to your cursor and to slowly gravitate toward it. If you hold the Option (Alt) key while dragging, the reverse effect applies, and instances move further away from your cursor.

• Symbol Sizer tool. The Symbol Sizer tool scales symbol instances within a symbol set. Clicking and dragging with the Symbol Sizer tool causes instances to become larger. If you hold the Option (Alt) key while dragging, the reverse effect applies, and instances become smaller.

• Symbol Spinner tool. The Symbol Spinner tool rotates symbol instances. Clicking and dragging with the Symbol Sizer tool causes instances to rotate toward the direction of your cursor. As you drag, arrows appear that indicate the direction in which the instances will rotate (Figure 5.23, next page). Instances that appear closer to the center of the area of influence rotate at a lesser rate than objects toward the edges of the area of influence.

  Figure 5.23. When dragging with the Symbol Spinner tool, arrows appear, helping you get an idea of how the instances will rotate.

  

  
  

  

  When using the Symbolism tools, you'll often find yourself jumping from one Symbolism tool to another. You can either tear off all of the Symbolism tools to access them easier, or you can use a special context-sensitive menu. If you're on a Mac, with any of the Symbolism tools selected, press Control-Option and click with the mouse. If you're on Windows, press Alt and right-click with the mouse to access a circular contextual menu that contains all of the Symbolism tools (Figure 5.24). Mouse over the tool you want and release the keys to switch to the Symbolism tool you have chosen.

  
  

  Figure 5.24. The Symbolism contextual menu makes it easy to switch between the tools.

  

  
  
  
  

• Symbol Stainer tool. The Symbol Stainer tool applies color tints to symbol instances. To use the Symbol Stainer tool, you must first select a color from either the Control, Swatches, or Color palettes. Once a color is selected, clicking and dragging with the Symbol Stainer tool gradually tints the symbol instances. If you hold the Option (Alt) key while dragging, the reverse effect applies, and the instances will gradually return to their original color.

• Symbol Screener tool. The Symbol Screener tool applies opacity to symbol instances. Clicking and dragging with the Symbol Screener tool causes instances to become transparent. If you hold the Option (Alt) key while dragging, the reverse effect applies, and instances become more opaque.

• Symbol Styler tool. The Symbol Styler tool applies graphic styles to symbol instances. To use the Symbol Styler tool, you must first select a graphic style from the Graphic Styles palette. Once you've selected a style, click and drag with the Symbol Styler tool to gradually add appearances from the style to the symbol instances. If you hold the Option (Alt) key while dragging, the reverse effect applies, and the instances gradually return to their original appearance. Note that using this particular tool can result in extremely slow performance, especially with complex symbols.

Double-click any of the Symbolism tools to see the options for the entire Symbolism toolset (Figure 5.25). The Intensity setting controls how quickly the Symbolism tools work, and choosing Pressure for the Intensity setting if you have a pressure-sensitive tablet makes it easier to control the flow of symbols and the edits you make to them.

Figure 5.25. In one dialog, you can set the behavior and view options for all of the Symbolism tools.

Expanding a Symbol Set

You can reduce a symbol set to a group of individual symbol instances by selecting the symbol set and choosing Object > Expand. Although the Symbol Sprayer only works with symbol sets, the remaining Symbolism tools work on individual symbol instances. You can also select several symbol instances and use a Symbolism tool to adjust them all at once. Still, you'll find that most times, you'll be using the regular Scale and Rotate tools to adjust individual symbol instances, and the Symbolism tools for when you're working with symbol sets.

If you add multiple symbols to a single symbol set, using any of the Symbolism tools only affects the symbol that is currently selected in the Symbols palette.

Featured Match-Up: Scatter Brush vs. Symbol Sprayer Tool

You may be wondering why there's a Symbol Sprayer tool in Illustrator, since you know that earlier in the chapter, we discussed the Scatter Brush, which allows you to distribute graphics along a path.

Although the concept of creating multiple copies of art is common between the two, the differences end there. A Scatter Brush is limited by what can be defined as a brush, whereas there are far fewer limitations when you are defining symbols. Additionally, using a Scatter Brush to add many shapes to a file increases file size and adds complexity to the file. The Symbol Sprayer tool can spray hundreds of symbols onto a page without you having to worry about files getting too big or too complex to print.

Of course, you can adjust symbol sets that are created with the Symbol Sprayer tool using a range of Symbolism tools. This allows you to tweak and massage a design until you're happy with the results. In contrast, when using a Scatter Brush, you've already specified the settings of the brush before you've created the path. However, a Scatter Brush can follow a specific path, whereas the Symbol Sprayer tool is harder to control if you need art placed at specific intervals.