BRYCE MODEL We can easily produce stereo views like this from any 3d model in any 3d software. I have been doing this with Bryce v.2.1 for several years. Although theoretically a very simple process - creating two renderings, one viewpoint for each eye - the devil lurks in the details. Two concepts are very important to understand: parallax and the stereo window. The most common errors made in the creation of stereo pairs involve the development of too much or too little parallax, and improper placement of the stereo window. Parallax is the rate at which apparent disparity increases with real depth. When you create stereo pairs, parallax is determined by the distance the camera is moved between the two viewpoints (the stereobase) and by the field of view of the camera. This tutorial gives you a "seat of the pants" method for controlling parallax, that automatically incorporates both of these variables. The stereo window is the apparent frame through which the three dimensional image is perceived. Just like looking through a real window, it is pleasing for the mind to see most, if not all, of the scene behind the window. Things may poke through the window towards you (just as the ice grass does in our lead image), but it is disorienting for the mind to see things in front of the window, that are also cut by any edge of the frame. Objects that will touch or be cropped by the stereo window must appear to reside behind the window. But what does this mean in practice? Look out any window, right now. Without moving your head, notice the bounds that the window places on the scene outside for each eye. The left eye sees less along the left edge, and the right eye sees more along that same left edge. Keep this in mind for when we set the stereo window in Bryce. Preparing to Generate Stereo Rendering of Bryce Model Let's start with the simplified Ice Pond model here <http.etc>. The model is for Bryce v.2.1, but can be used in v.3 or 4 (some textures may not translate). The model is already set up to render the left viewpoint. The field of view is normal (35 deg.) Before we move the camera laterally, we need to take note of three visual landmarks. This is necessary to set a good stereobase, and then to set the stereo window. The first two landmarks will be the nearest and farthest objects in the scene. I say these are the upper tip of the nearest ice grass bush (tip of blue spike A) and the green rock at the top of the page (B). A happens to be vertically aligned with the right edge of B. (Figure 1.) Figure 1. The third landmark will be any object that you want to be in the plane of the stereo window. Everything further away than this object will be behind the window, and anything closer will appear in front of the window. Because of the design of this scene, this should be something coplanar with the water near the bottom of the image. I've marked a floating leaf red C down in the right corner to serve as this landmark. The only things closer to the camera than this leaf are the near ice grass blades - these will poke through the stereo window. Continue to Stereobase.

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