Simple RealPix Trix: The Flyby
by Tim Kennedy
February 24, 1999

If you have been writing SMIL for the RealNetworks G2 player, you have probably mastered the basics of their streaming pictures format called RealPix. Creating a slide show in RealPix is one of the most basic SMIL authoring skills. It is a great format. Streaming still images consumes less bandwidth than video. But after working with the format for a while, you may find RealPix limited. Indeed, there is only so much that you can do with still images that fade or wipe in the player window.

With a few simple approaches, however, you can create RealPix effects that offer more pizzazz. In doing so, that limited set of fades, dissolves, and wipes can offer more production opportunities than you might have realized on first glance.

In our first tutorial of our RealPix Trix series, we are going to create a simple moving flyby of a formation of Blue Angels planes. The planes will appear to move from left to right across the screen as if they really were moving. In a future RealPix Trix tutorial, we will add that effect in to a more complex panoramic scene.

Before we get started, let's talk about how we are going to get to our end destination. RealPix offers a tag called <wipe>. It allows you to wipe an image on the screen or off. It comes with two flavors. A normal wipe moves a new image in over the current image that remains stationary. A push wipe pushes the current image in while the old image is being pushed out. In this case, both images appear to move. For this tutorial, we will want to take advantage of the push wipe.