Creating Special Effects with Contours Because contour intermediate steps travel concentrically from the control object to the end of the effect, you can accomplish certain things that w
Trang 1Fill Color
If you want to wow your audience, definitely play with Fill Color to create significant changes along the steps of a contour If an object doesn’t have a fill, although you can set a contour color, the contour will not have a fill This creates an interesting effect if you have outline width and colors applied to the base object, but with no fill and no outline set for the base object to which you want to apply a contour, it’s an exercise in artistic futility To set the fill color, click the Fill Color selector and choose a color
Although base objects cannot have a transparency effect in place when you use the Contour tool, you can do some interesting things if you first create a contour, break
it apart ( CTRL+K ), and then apply the transparency effect to the group of objects that used to be a dynamically editable contour Try using Uniform transparency at about 90% in Xor mode on a group of 10 to 20 objects Without a lot of preplanning, you can easily generate a color palette simply by experimenting.
Creating Special Effects with Contours
Because contour intermediate steps travel concentrically from the control object to the end
of the effect, you can accomplish certain things that would take hours or perhaps not be possible using other tools and effects For example, a blend effect is simply the wrong tool choice when you want interior shading in an object, because when you scale an irregularly
shaped object (such as the letter Q), it scales disproportionately As a result, when you blend, say, a Q to a smaller Q you’ve centered inside the larger Q, the intermediate blend
objects scale different areas disproportionately Therefore, a key to creating smoothly shaded objects is to use a contour effect with many steps and a small Contour Offset value Here’s
an example recipe: with the Artistic text tool, type the letter Q (uppercase), choose a bold
font such as Futura, use black as the Fill Color, and make it about 200 points in height With the Contour tool, choose Inside Contour on the property bar, set the Contour Offset to about 0.001", create about 150 steps, and choose white as the fill color The result is a very
smoothly shaded piece of artwork that will print beautifully with no banding, because 150 intermediate steps from black to white within relatively small objects is just about the upper limit for laser printers and most inkjet printers
Grayscale images—those composed only of shades of black—are usually written to
an image file format such as BMP and TIFF as 8-bit-per-pixel images Eight bits of brightness values yield 256 possible shades from black to white, and this number is
a good one to remember when you want to create smooth transitions with the blend and contour effects In theory, you should see no banding in contour steps if you use 254 steps between a white and a black object of small size on your page The greater the distance between blend and contour effect objects, the greater the chance you’ll need to increase the number of steps, but 254 is a good bench value
to begin your work with if a smooth transition is your goal.
Trang 2However, a smooth contour transition might not always be your artistic goal; by using
no fill but only an outline width on objects, a small number of steps, and a relatively high
Contour Offset value, you can indeed design topographic maps, magnetic fields, and other
illustrations in the technical vein In Figure 21-29 you can see an object with the top edge
suggesting a landscape—created by using the Roughen brush The contour objects are white
lines, they have a high Contour Offset value so they’re clearly visible, and then the Effects |
Add Perspective command was used to suggest contour effects that have depth in the illustration
The text also has a contour effect; a Linear transparency was then added from top to bottom
Fountain Fill Color
Contour effects also support the use of certain fountain fills in linear, radial, conical, and
square modes If you’ve applied a fountain fill to your original object, the color fill properties
of the contour group are also applied with the same fill type If you’ve contoured an object that
has a fountain fill, use the property bar to set the last color in the Contour fountain fill; if the
fountain fill uses multiple colors, the Contour fountain fill ignores the transition colors If an
object doesn’t include a fountain fill, the color selector on the property bar is unavailable
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FIGURE 21-29 Make smoothly shaded contour effects or make the effect obvious; the
technique you choose depends on the illustration assignment
Trang 3Copying and Cloning Contour Effects
You can also copy and clone contour effects to other objects, just as with blends as discussed earlier To perform either operation, the effect you want to copy or clone must be in view on your screen at the same time as the object to which you want to copy or clone the effect To copy an existing contour effect to your selected object while using the Contour tool, first click a target object to which you want to copy the effect Then click the Copy Contour button on the property bar, and use the targeting cursor to click an existing contour effect You can also use the Attributes eyedropper tool when you’ve checked the Blend entry in the Effects drop-down list on the property bar While using the Pick tool, select the target object first, and then choose Effects | Copy Effect | Contour From, and use the same targeting operation To clone a contour effect to a selected object, use the Pick tool and choose Effects
| Clone Effect | Contour From, and target the existing effect
Controlling Contour Acceleration
Just like blends, Contour Acceleration options have the effect of either increasing or
decreasing the rate at which the contour group objects change shape (and color) as they progress between the control object and the final object You can choose Object and Color Acceleration options on the property bar when a contour effect object is selected in the drawing window When a default contour is applied, both these settings are at a default midpoint—the contour objects change in color and size evenly Change both acceleration rates simultaneously (the default) while the two options are linked, or change them
individually by clicking the unlink acceleration (lock icon) button, shown here
Ill 21-13
To access acceleration options, click the Object And Color Acceleration button in the property bar, and adjust the slider controls and/or choose the unlink acceleration button Moving sliders to the left of the center position reduces (or slows) the acceleration rate between the control object and the final contour in the effect Moving sliders right increases the acceleration While the two acceleration options are unlinked, changing the object acceleration affects only the progression of shapes in the contour group Figure 21-30 shows the effects of increasing and decreasing acceleration
When the Object Acceleration slider is unlinked, changing the Color Acceleration affects only the change in progression of the fill and outline colors between the control
Click to unlink Object and Color Acceleration sliders.
Trang 4object and the final contour in the effect, leaving the object shape acceleration unchanged.
Moving the sliders (or interactive markers) left or right increases or decreases acceleration
between the control object and the final contour Figure 21-31 shows the results of changing
the Color Acceleration rates while unlinked from the Object Acceleration values
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FIGURE 21-30 Acceleration rates can dramatically change the look of an object that has a
contour effect
Object Acceleration increased, slider moved right of center.
Object Acceleration decreased,
slider moved left of center.
FIGURE 21-31 Acceleration rates are unlinked; you can increase and decrease the
illustration’s contrast by changing only the Color Acceleration
12 contour effect steps;
default Color Acceleration
The same 12 contour steps;
Color Acceleration increased, slider moved right of center
The same 12 steps; Color Acceleration decreased, slider moved left of center
Trang 5Changing the Color Acceleration also affects the color properties applied to outline paths of objects.
Using Contour Presets
Up to this point, you’ve learned about the effects of changing contour direction, steps, offsets, color rotation, and pen and fill colors of applied contour effects Next, it’s only natural to save your efforts as presets to apply to other existing contours using the Presets options, as shown here:
Ill 21-14
Contour presets are used in the same manner as other preset effects Contour presets can
be saved and quickly reapplied to different objects
Using the Contour Docker
Although the Contour tool is the most intuitive way of applying contours, you can still apply them using the old Contour docker as an alternative
To open the Contour docker, shown next, choose Effects | Contour, or choose Window | Dockers | Contour (CTRL+F9) The Contour docker is organized into three areas accessed by clicking buttons for Steps, Color, and Acceleration The docker’s options are organized a little differently than on the property bar, but the same options are found here One advantage
to using the docker is that as with the Blend docker, you can choose all your options before applying them
Contour preset list
Click to add selected contour effect as preset. Click to delete selectedcontour preset from list.
Trang 6Ill 21-15
In this chapter you’ve seen where to find the options for controlling and customizing
blends and contours, so you know where things are, but as with operating heavy machinery:
● You don’t take prescription medicines an hour before beginning
● You turn the key and the real fun begins!
Dig into blend and contour effects; add shading to simple objects to make workaday
illustration work an inspiring endeavor and to reap the reward of the automation that’s
possible within CorelDRAW You can knock off 20 signs an hour using these effects instead
of only two or three Don’t forget, either, that you can break these effects into groups
(CTRL+K), ungroup the objects (CTRL+U), and rearrange the objects to suit your specific
assignment Blends and contours are one of the best ways to generate scores of similarly
shaped objects, so fill your page with tiny drawings to make patterns, charts, you name it
Chapter 22 continues with a survey of CorelDRAW effects, turning now to applying
photographic qualities to your drawings through transparency, shadows, glows, and lens
effects Bring along some drawings you want to spruce up, and also bring your thinking cap
Specifically, your lens cap.
You can groan now…
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Steps
Color Acceleration
Trang 8Lens Effects, Transparency, Shadows,
Glows, and Bevels
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Trang 9When you need something more than distortions, blends, and contours, but your
design doesn’t require a full-blown 3D extrude look, elements of photorealism can
push a design in your intended direction This chapter takes a look at automated—and a few manual—techniques you can use to add shadows, an engraved look, and reflections and highlights to a composition You’ll also learn to use the Lens docker, a device for color correcting both vector and bitmap artwork Many looks you’d like to achieve that use transparency, or a distorted, colored look through a virtual camera lens are easily
accomplished with lens effects The only hard part is deciding what type of effect works best in your illustration!
Download and extract all the files from the Chapter22.zip archive to follow the tutorials in this chapter.
What’s Behind a Lens Effect
Looking at your drawing with a lens effect object resting above it is like looking through a window or a magnifying glass What you see through the lens effect object is influenced by
the properties of the glass For example, tinted glass in the real world makes objects in the
distance appear darker—this phenomenon can be easily simulated by using the Color limit lens applied to a 50% black object
The remarkable thing about lens effects is that this feature doesn’t care whether a lens effect object is over a vector drawing or a bitmap—you’ll get the same results One of the more popular uses of this feature is to partially overlap a shape possessing a lens effect over
a drawing area, to see affected and original areas at once In addition to putting a lens effect shape over a drawing area, you can freeze the lens object, capturing whatever’s underneath the lens, and then move the lens object around, retaining the original view within the object
Using the Lens Docker
Later in this chapter the Transparency tool is covered; this tool can create wonderful shading effects, and its function slightly overlaps some of the lens effects features Let’s start with
the easier of the two effects, which is called in sections to follow simply the lens.
The only way to apply a lens in CorelDRAW is through the Lens docker, opened by choosing Effects | Lens (ALT+F3) Figure 22-1 shows the Lens docker, whose options change depending on the function you choose The way to operate the Lens docker is to first place
an object—which becomes the lens object—over a different object (or several objects, vector
or imported bitmaps), pick a lens type from the drop-down menu, and then choose among different property options
When an object is selected, the Lens docker preview window shows a thumbnail of what you’re about to apply; if no objects are targeted for the effect, the preview window features a graphic of a circle over a rectangle Options are covered in following sections, but for now, let’s take the Lens docker out for a trial spin
Trang 10Selecting the Lock button on the Lens docker causes lens effects to be applied
immediately with no need to click the Apply button.
Working with a Lens Effect
1. Create a rectangle and then with the Interactive fill tool, click-drag to create a
default linear fountain fill from black to white This rectangle will serve for this
demonstration; you’ll most certainly get better effects using artwork of your own
2. Create an ellipse and then with the Pick tool arrange the ellipse so it partially
overlaps the rectangle, so you can better see the creative possibilities of applying a
lens to the ellipse object
3. With the ellipse selected, open the Lens docker (ALT+F3)
4. Choose Custom Color Map from the docker’s selector drop-down list Choose a
deep blue from the From mini-palette, and then choose a bright green from the To
mini-palette
5. Click the Apply button The lens effect has remapped deeper shades in the rectangle
to blues and remapped lighter shades to greens But areas of the rectangle not
covered by the ellipse are still a black to white fountain fill
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FIGURE 22-1 The Lens docker is where you customize effects to create a specific type of lens
you need
Preview window
Lens selector
Lens options
Viewpoint options Lock button
Click to apply selected lens