POV / ForeSpace OS/2 - by Dr. Dirk Terrell

he Persistence of Vision raytracer, or POV-Ray for short, is a very popular cross-platform raytracing tool that dispels the myth that free software is somehow inferior to commercial software. Written in portable C code, POV-Ray is available for just about every major platform from DOS to Unix, and the source code is available so that people can port it to any system not officially supported by the POV-Ray team. Not surprisingly (to this veteran OS/2 user anyway), the POV-Ray team does not (yet) have an "official" OS/2 port, but others have taken the source code and produced OS/2 executables.

POV-Ray is a very powerful tool for producing photorealistic 3D images, and is capable of producing some startling images in the hands of talented artists. Unfortunately, the program has one hindrance for casual users: it has no graphical interface.

Interfaces

However, there are third party programs that make the creation of input files for POV-Ray much easier for beginners. One such front end for OS/2 is ForeSpace OS/2 (note that by "front-end" here I mean a modeler for building scenes and not just a graphical front end to executing POV-Ray, of which there are also several for OS/2, such as POVFront). Without a graphical modeler, you would have to create POV-Ray input files in a text editor and do trial and error traces to get things the way you want them. As you can imagine, REXX is a very powerful tool when used to create input files and execute POV-Ray.

Objects and Tools

Like all good 3D raytracers, POV-Ray has a selection of basic objects such as spheres, boxes, cones, cylinders, planes, and quadric surfaces (among others). It also has some very powerful functions for combining objects as unions, intersections, differences, etc. by using Constructive Solid Geometry (CSG). For example, creating a box with a hemisphere cut out of it is a trivial task with POV-Ray. One of POV-Ray's most flexible objects is the height field, which enables you to make some very realistic natural scenes such as landscapes by using a 2D image whose colors represent the height of the landscape at each pixel.

POV-Ray also has some more advanced types of objects such as tori, bezier patches, blobs, smooth triangles, text, fractals, superquadrics, surfaces of revolution, prisms, polygons, lathes and fractals. In short, just about any shape you can imagine can be modelled with POV-Ray.

Of course, the shape of an object is, if you will, only part of the picture. The texture of an object (its color and other surface properties such as roughness, reflectivity, etc.) plays a crucial role in the realism of a rendered scene. And POV-Ray gives you just about every conceivable control of textures. You can control, among other things, color, transparency and index of refraction, reflectivity, and normal (bumpiness, wrinkles, waves, etc.).

The latest version of POV-Ray (Version 3) added a long-awaited texture called a halo. A halo texture enables you to simulate the interaction of small particles with light. Some examples of this would be a room with lots of dust floating around or a nebula in space.

(Click the image for the full-size version, but be advised that this image is rather large at 354K.)

Light sources are obviously important in raytracing and POV-Ray supplies several types: point sources, spotlights, planar (area) lights and cylindrical lights. You can also control whether a light casts shadows. Shadowless lights (or ambient lights) are useful when you need to fill in some dark areas of an image but you don't want it to look like there is a light source present. You can even make a light source that looks like another object, convenient for things like light bulbs.

ForeSpace OS/2

So, POV-Ray is very powerful raytracing engine, although its command line interface will unfortunately cause most people to dismiss it. These days people don't want to use text editors and batch files to accomplish tasks. Fortunately, people have created modelers for POV-Ray that eliminate a lot of the drudgery of using POV-Ray. ForeSpace OS/2, by Sean Ryan, is a modeler that enables you to graphically create and edit objects and their textures, and composite them into scenes that can be rendered with POV-Ray. I frequently use ForeSpace OS/2 to lay out a scene, and then manually edit the POV-Ray input file that it creates to put the final touches on it.

Although ForeSpace OS/2 is still in the development stage, it is already very useful in its current state. You can add objects to a scene and edit their properties (size, shape, etc.) as well as edit textures for the objects. But since the product is in development, you may run into problems as the development continues, such as old scene files being incompatible with new versions of the program.

ForeSpace OS/2 has been around for a while, but development progressed slowly as the development environment was changed to the VisualAge compiler. Recently, though, progress has been made, and ForeSpace OS/2 is turning into a very nice tool (although it is still incomplete). I encourage you to take a look at it, and if you like it, give the author some feedback and support. Projects like this thrive or die on the feedback from users.

Conclusions

If you are looking for a professional, commercial quality 3D modeler for OS/2, then NeoN GRAFIX 3D is for you. If you are on a more constrained budget or perhaps just want to play around, take a look at POV-Ray for OS/2 and ForeSpace OS/2. They lack the polish and some of the features of NeoN GRAFIX 3D, but they are free to use and powerful enough to do just about anything you can imagine. Some of the work I've done with POV-Ray can be found on my personal page if you'd like to see what can be accomplished on an OS/2 machine.

POV-Ray

by the POV Development Team
download from the POV-Ray FTP site (ZIP, 1.5M)
Registration: FREE

ForeSpace OS/2

by Sean Ryan
download from Sean's web site (ZIP, 1.3M)
Registration: FREE

Dr. Dirk Terrell is an astronomer at the University of Florida specializing in interacting binary stars. His hobbies include cave diving, martial arts, painting and writing OS/2 software such as HTML Wizard.

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