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CHAPTER 7: EFFECTS AND TRANSITIONS ■

3D Warp (Xpress Pro)

Xpress Pro has additional effects that emulate 3D space. Let’s go over some basic con-

cepts and then look at each type of effect.

We’ve already discussed how we can manipulate the horizontal and vertical

axes, respectively known as X and Y. Now let’s focus on the depth axis, known as Z.

To give objects depth on the screen, the Z axis can be adjusted so that what normally is

a flat item (such as a video image, which is flat) needs to be manipulated so that pixels

emulate the effects of a third axis, showing depth.

We emulate a third axis frequently when using the scale parameter of an effect.

For example, if we want an image to fly from infinity to full screen, we can adjust a

resize effect so that an image enters at zero size and increases to 100 percent, giving us

the impression that it is coming toward us.

But the problem with this type of faux 3D effect is that there is nothing to indi-

cate that there is any true depth of space in the picture. The scaled image is flat, so

there is nothing to show that there is a true dimension. As a result, these effects seem

rather tired.

To allow us to create that third dimension of depth, 3D on Xpress Pro takes

form in three different shapes: page folds, balls, and slats (see Figure 7.22).

Page Fold Page folds have been used in video effects for decades. They give the impres-

sion that a page from a book is being turned, complete with the sense of depth in the

curled portion of the video. Video editors have commonly used this effect to indicate a

change in subject or scenery.

Balls A 3D ball is not just a circular wipe: It can show portions of a picture with a

true Z axis, forming what appears to be depth in the picture. The image is distorted in

a circular fashion to express depth, and it can be spun, to a degree, to implicate a ball

shape. The parameters within the Shape parameter can further affect the 3D look of

the 3D ball, changing the amount of distortion that is applied and other parameters.

Slats Without a Z axis, the slat shape would appear to be a horizontal wipe. The dif-

ference here is that as the slats come onto the screen, the image is distorted so that

there appears to be some depth from the “front” of the slat where the image is closer

to us, and the “back” of the slat, where it is farther away.

Figure 7.22 Left,a page fold; center,a ball; right,a slat

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