CompuServe Messages

Lee, Imagine's Forms Editor lets you create objects by defining a series of key cross-slices and having the program interpolate them to the desired precision. Like (almost) all 3-D programs, it has a Front, Top and Side window, plus a Perspective window which will display the object from any angle. If your object was constructed as a series of horizontal slices, running from top to bottom, you could zoom in the Top window to full-screen and use any PD screen-capture program to create a series of IFF images, which could then be printed. This basically sounds like what you want to do. i A CAD program is a geometrically-oriented drafting program. Its strengths lie in the absolute precision with which you can size and place your elements. All good CAD programs let you define up to 255 layers, which can be viewed or printed separately or in any combination. Many CAD programs work in three dimensions. Ray-tracing is simply a method used by the computer to render a view of a 3-D scene. In ray-tracing, the computer casts a series of light rays that start at the observer's "eye" position, pierce the computer screen at each pixel, and then are let free to bounce off and penetrate objects in the scene beyond the screen. This allows the computer to fully represent shadows, illumination, reflections and refraction. It also takes a long time to produce an image — from an hour to a day is typical for a non-trivial scene rendered on a fast Amiga. Another method is called scanline rendering, which still gives you the perspective, transparency and illumination effects, but doesn't take into account refraction or the reflections of objects onto one another. (You can have objects reflect a "world map", an image of the environment such as clouds and ground, which gives you a more realistic picture) Scanline rendering is much faster than ray-tracing, and thus more often used. Blaq!