Editing a Blend
Once you've created a blend, you can edit it in a variety of ways. Because blends are live in Illustrator, you can adjust them even after you apply the blend. Using the Direct Selection tool, click a key object, and then change its color, shape, position, attributes—whatever. Illustrator redraws the blend to incorporate your changes.
You can't select or edit the intermediate steps that Illustrator creates to form the blend. This is an attribute of the live functionality of the blend—you can access the steps only by expanding the blend. (See the later section "Releasing and Expanding Blends" for details.) However, you can control how Illustrator draws blend steps:
- Select the blend and choose Object > Blend > Blend Options to display the Blend Options dialog box.
- Specify the desired Spacing setting (see Figure 4) to determine the number of blend steps that are created:
- Smooth Color. With this setting, Illustrator creates as many steps as necessary to display a smooth and gradual transition between key objects.
- Specified Steps. Use this setting if you want to define exactly how many blend steps Illustrator creates. Using a higher number of steps results in a smoother transition, whereas a lower number allows you to see the individual steps in the blend.
- Specified Distance. This setting controls how far apart each step is from the next.
When you want to create shading techniques using blends, the Smooth Color option provides the best results. When creating steps for a Flash animation, specifying fewer steps improves playback performance.
Figure 4 The Blend Options dialog box offers spacing and orientation options for blending.
- Specify the desired Orientation setting (see Figure 5). The Orientation setting controls the baseline angle of each step in your blend:
- Align to Page. With this setting, each blend step aligns parallel to the bottom of the page, even if the path is curved or diagonal. With this setting, all blends steps share the same orientation.
- Align to Path. Aligns the baseline of each blend step to the angle of the path. With this setting, each blend step has a different orientation.
Figure 5 The blend on the left uses the Align to Page orientation. The blend on the right uses Align to Path.
- Click OK.
Replacing the Spine of a Blend
The path that connects the key objects in a blend is called the spine. The individual steps in a blend follow along the spine as they connect the two outer objects. The spine is an editable path, and you can use the Pen tool and the Direct Selection tool to edit the path if you want to alter the direction of the blend steps. In fact, the position of the control handles on a spine can control how the individual steps are distributed along the spine.
Additionally, you can perform a delicate operation—let's call it a "spine transplant." You can draw any vector path, open or closed, and use it as the spine for an existing blend. To perform this surgery, select both the blend and the path you've created, and then choose Object > Blend > Replace Spine. Illustrator uses the path you created as the spine for the blend, allowing you to customize how blend steps appear.
With a blend selected, you can choose Object > Blend > Reverse Spine to reverse the order of the key objects in your blend. This function is helpful when you want to flip the blend so that it travels in the opposite direction.
Additionally, you can reverse the stacking order of the key objects in a blend by selecting the blend and choosing Object > Blend > Reverse Front to Back. This setting is especially useful when using blends to create animations, which always travel in one direction. Use this feature to play your animation in reverse.