This stop on our tour through CorelDRAW's special effects might be the highlight of the trip for you. It features one of DRAW's most celebrated attributes: its ability to create transparent objects. Unlike effects such as Envelope and Extrude, which influence how an object is shaped, DRAW's transparency tools determine how we see an object. DRAW splits its transparency tools into two categories, each with different functionality: the Interactive Transparency tool and the Lens docker. We suspect that Corel still wants to evolve these features, because there is no apparent reason why the Lens effects couldn't be an interactive set of tools with a property bar, like all the others. This chapter is similarly divided into two; we'll start with the lenses.
New Lenses on Life
Lenses have historically been responsible for more oohs and aahs at trade shows and product demonstrations than any other feature of CorelDRAW. The Lens docker provides access to 11 different camera-like lenses that can be applied to an object. When you apply a lens, the object becomes the lens, filtering your view of all objects that are beneath it. Thus lenses allow objects to become, in essence, transparent- an effect that was impossible prior to their debut in DRAW 5.
In the past, to qualify to be a lens, objects had to be combined into a single curve, but no longer. Now any group of objects - even a multiple selection of separate objects - can act as a lens. An artistic string of text can also be a lens; paragraph text cannot.
You control the lens effect with the Lens docker, shown in action here (28K). You get there from Effects| Lens or by pressing Alt+F3. Here, an inversion lens is being applied to the ellipse in front of a collection of graphics. This lens studies the colors of objects underneath and converts them to the colors that are on the opposite end of the CMYK color spectrum. Red becomes cyan, green becomes magenta, and white becomes black. We intentionally drew the ellipse to hang over the edge of the graphic so you could see that it even turned the white page black.
CorelDRAW's Lenses
Here are descriptions of lenses:
Transparency: This is likely to be the most used effect but the least used lens, and we'll explain what we mean in a moment. Transparency causes the colors of the objects under the lens to mix with the lens object's color, creating the illusion that you've placed a piece of transparent film over the object. In the Rate box, you enter a transparency rate from 1% to 100%. The greater this value, the more transparent the lens object; at 100%, the lens essentially disappears, allowing 100% of the underlying object's color to show through unchanged. However, while transparency is a popular effect, you probably won't reach for Lens to apply it, thanks to the Interactive Transparency tool, discussed later.
Brighten: This lens brightens the colors under it by the factor you specify in the Rate box, between -100% and 100%. At 100%, the colors are nearly white; at 0%, the lens has no effect at all; and at -100%, the colors approach black.
Color Add: The Color Add lens mixes the colors of overlapping objects, adding the color of the lens object to that of the underlying object. This lens has no effect where it overlays white objects, because white already contains 100% of every color.
Color Limit: Color Limit works much like a color filter on a camera, filtering out all colors under the lens except the one you specify in the Color box. For example, if you place a green lens over an object, all colors except green will be filtered out within the lens area. You can also control the strength of the filter by specifying a value in the Rate box. For the green filter, a rate of 100% will allow only green to show through; a lower setting will allow other colors to show through.
Custom Color Map: This lens maps colors using a range that you define. The controls are similar to fountain fills-you choose From and To colors, and specify the direction that the mapping should take. You can map directly between the two specified colors or start with the From color and go through the colors of the rainbow, forward or backward, to the To color.
Fish Eye: Just like the camera lens of the same name, this lens magnifies and distorts the objects behind the lens. The figure here (20K) shows the process of creating a fish eye effect. The Fish Eye lens works when the objects it is distorting are objects drawn in DRAW - it has no effect on bitmaps.
Heat Map: This lens is DRAW's contribution to the electronic psychedelic community. It maps colors to other colors in a predefined palette, creating a heat map or infrared look. Bright (or hot) colors are mapped to other hot colors (yellow, orange, and so on), and dark (or cool) colors are mapped to cooler colors (blue, cyan, and purple). The palette Rotation value determines where the color mapping begins. For example, a value of 0% or 100% causes mapping to begin at the start of the palette (at white) and move to the right (through cyan, blue, and so on). A value of 50% causes mapping to begin halfway through the palette (at red) and move to the right, and then go back to the start of the palette.
Invert: With Invert, you can switch the colors under the lens to their complementary colors, based on the CMYK color wheel. We used Invert to show the Lens docker mentioned earlier.
Once a lens is applied, you can select colors from the on-screen color palette or the Fill docker to change the lens tint. That way, if the docker is closed, you don't need to reopen it to change the lens.
Magnify: This lens causes the objects under the lens to be magnified by the factor you specify in the Amount box, so it looks like you've placed a magnifying glass over the drawing. The maximum magnification factor is 100. Be careful when using this lens with bitmaps; at twice or three times the magnification, most bitmaps will look very jagged. However, with a vector object, like the coin shown here (38K), the effect is useful and realistic.
Tinted Grayscale: Objects under this lens appear to have had a tonal scale setting applied - the underlying objects appear in monochromatic tones of the lens color. Colors under the lens are mapped to an equivalent tone of the color of the lens. For example, a blue lens over a light-colored object creates light blue and the same lens over a dark-colored object creates dark blue. This lens is very handy for decolorizing a drawing or an imported bitmap, for proofing, or for actual printing. To do this, simply cover the entire object with a rectangle or other closed curve, choose Tinted Grayscale, and set the color to Black.
Wireframe: This clever lens is like switching to Wireframe view, but for just a portion of your screen. Try it on the included file "lenstour.cdr" and you'll see instantly how it works. All objects are reduced down to one fill and one outline color, both of which you designate from the Lens docker.
No Lens Effect: Selecting None removes the lens from the selected object and returns the object to its normal state.
Using Brighten to Create Text Backdrops
Another popular technique used in many publications is to brighten or "wash out" part of an image to place text over it. The Brighten lens makes it easy to accomplish this.
The Miracle of Interactive Transparency
Our lead author relates a recent experience at a California seminar:
I was on a tour of six cities, in which I met over 300 CorelDRAW users. Most everyone exhibited symptoms of version-itis, an uncommon, but rarely fatal condition in which software users develop the inability to recall which version brought about which new features. I, too, am not immune, regularly failing to remember if PowerClip was introduced in version 4 or 5, and when DRAW began supporting page sizes over 30 inches.
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CorelDRAW users are the most susceptible, given the dizzying pace with which Corel Corp. develops new versions. I was particularly struck by the amazement that greeted me from skilled version 7 users who attended these seminars to learn more about version 8. They encountered several features they had never seen before...only to learn that version 7 sported them also.
This was most widespread with Interactive Transparency. At each city, when I melted one image into another - an effect normally reserved for Photo Paint users - legions of seminar attendees began gasping and taking frantic notes. "And how much RAM does version 8 need to do this?" was one of several typical queries. "No more than you have now. This effect is available within version 7." Stunned silence was often the last word of this exchange.
Here it is version 9, and we suspect that many of you are still just getting to know this incredible tool. It does not produce as many effects as the Lens does, concentrating instead on the one lens effect, transparency, used by most users. As an interactive tool, it offers several usability advantages over the docker; and as a more refined tool, it offers functionality that the Lens can't touch.
Interactive Transparency, the 10th icon in the toolbox, operates like all of the other interactive tools that you have read about:
- Select an object.
- Activate the tool.
- Work the controls on screen or on the property bar.
To use Interactive Transparency effectively, remember the following points:
- No More Docking and Applying: You can dispense with the Lens docker for standard transparency effects, as Interactive Transparency works straight off of its property bar. No more having to fetch the docker, and no more incessant clicking of an Apply button.
- Just Like Filling an Object: Interactive Transparency works just like the Fill tool in its range of possibilities. But instead of applying a color, shade, or pattern to an object, you are applying a degree of transparency to it. (Technically, the same engine is used: when you apply transparency to an object on top, DRAW creates the effect by changing the fill pattern of any objects underneath.) Forget the nerdspeak; the essential point here is that you can create transparencies that are themselves fountains, patterns, or textures. The latter two are risky and carry a very high ugliness quotient, but fountain transparencies are very useful and potentially dramatic.
- Transparent Anything: Prior to version 7, you could only apply transparency to vector objects created in DRAW. In addition to its interactive qualities, version 7 also introduced the capability of applying transparency to any object on a page, including imported bitmaps (thank you, Xara, the diminutive drawing program that scared Corel so much, the company bought the licensing rights to it). Simply put, if you can select it, you can apply transparency to it, the lone exception being an imported placeable .eps file.
Thanks to Interactive Transparency, amateur and semiproficient DRAW users can create effects that they would never have dared to attempt in the past. We include our lead author in that category. "Producing surreal effects has always been well outside of my artistic resume," he says, "requiring expertise with image-editing software or the wherewithal to be able to communicate my vision to the camera people at my printer. But now that DRAW can do it...I can do it."
The figure here (28K) is a relatively simple example - one of countless advertisements that attempts to mix baseball with patriotism. You are looking at two distinct imported photographs - the flag's background has been removed. With the flag selected, the Interactive Transparency tool can apply any degree of transparency to it, in this case, 75% transparency.
This entire effect can also be produced in Photo Paint. In fact, some would argue that it's easier to do it there. We won't participate in that argument because it is a moot point to many. Despite the big upswing in Photo Paint interest, many DRAW users feel more comfortable in the vector environment. The fact that this effect can be produced in DRAW is front-page news to these users.
The Downside...
As with all of DRAW's effects, transparency can be dangerous if it falls into the wrong hands. First off, if you place transparent objects on top of bitmaps, you can end up with gigantic files (particularly if the transparent object is itself a bitmap). DRAW might lull you into a false sense of security if you save the .cdr files with bitmap compression turned on; when you create your print files, be ready for the dam to burst. Transparency is a complex effect, and aside from large print files, they are a leading cause of RIPing problems at service bureaus. If you encounter this, try converting the transparent effect into a bitmap. This might sound strange - converting a bitmap into a bitmap - and removing the intelligence from DRAW's tools is not exactly what you had in mind when you adopted the program.
But a little bit of dummying down can be a good thing. When you convert a transparent bitmap effect into a static bitmap (done by selecting the objects and going to Bitmaps| Convert to Bitmap), you essentially freeze the effect in time - you are taking a snapshot of what the effect looked like at that moment. In so doing, you greatly simplify the work. Now it's just a bunch of pixels, and any old Mac-myopic service bureau can RIP a bunch of dumb pixels.
We regularly employ the following routine when preparing print files that might contain troublesome effects:
- We save.
- We convert any suspect effects to static bitmaps.
- We create the print file.
- We close without saving.
Now any changes that need to be made to the effect can easily be done as the effect is still live. Once we make the change, we repeat the four steps.
DRAW 9 adds a print option to rasterize an entire page, essentially converting all elements to bitmap. This is more convenient because it doesn't involve your converting any of your elements (it's done transparently at print time), but its downside is that it converts all elements, including your text. This should be considered a drastic measure.
The second major risk to all of this is ugliness, and there we have no quick fixes to offer, except to suggest that you try to avoid it. As with all of DRAW's effects, transparency will haunt you and taunt you into using it just for the sake of using it. You must resist with all your might the use of transparency simply because it's there.
But when it's used at the appropriate time, it can be terrific. It is one of the tools that can truly take you to another level of design as it allows you to create effects that you might have envisioned but never knew how to create.
Now you can...
This is an excerpt from Rick Altman's upcoming book from SYBEX Inc., Mastering CORELDRAW 9 (ISBN 0-7821-2520-4), available now. For more information or to place an order, visit Sybex's "Mastering..." series page.
Have an opinion? Share it with the Corel community at the CorelWORLD Forum. Lots of participation and regular visitors, so please join in.
Copyright 1999, All rights reserved. R. Altman & Associates.
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