Megahedron—A 3D Graphics Environment

The world of 3D graphics on Linux has come a long way in the past 2 years. When I first started investigating graphics tools for Linux, there were only a handful of 3D renderers publicly available and almost no 3D modelers. Since then the number of modelers has grown significantly (I can count 5 full-blown modelers currently working plus at least 2 others in development). 3D rendering tools have also seen a vast increase, with POV-Ray and BMRT (Blue Moon Rendering Tools) two of the best modelers available for any platform, heading the list.

Not long ago I came across a new product I had seen announced in the comp.os.linux.announce newsgroup: Megahedron. I hadn't actually used the product (it was, and still is, a commercial product) but I was intrigued by the announcement. I had Megahedron on my “list of things to purchase”, when Linux Journal beat me to it and provided me with a copy to review.

Megahedron is a modeler and 3D graphics engine that uses an interpreted language similar to POV-Ray's scene description language. It differs from POV-Ray in a numbers of areas, such as the ability to do wireframe animations on the fly and built-in network rendering. The package is supported on a number of platforms, including Windows NT (x86 and DEC Alpha), Silicon Graphics and Intel Linux. The $99 list price gets you a CD-ROM containing binaries and complete configurations for each of these platforms. Licensing covers any machine the purchaser uses with Megahedron, but if another user wishes to use it, he must purchase his own copy. It's a fairly unrestrictive license, as far as commercial products go.

The distributable package consists of a single CD in the customary plastic casing. All documentation is in HTML format on the CD. There is a single insert on the CD explaining where to begin in the documentation contained in an HTML file in the root directory named mhedron.htm. This page is a master Table of Contents for the complete documentation.

Installation of Megahedron is simple:

The only problem with installation is that the instructions are listed in the fourth part of the fourth section of the first chapter of the Manual. The Manual is the third heading in the Table of Contents. The second entry in mhedron.htm is a “Quick Tour”. This tour suggests making changes to source code, which can't be done directly from the CD, so you must first do the installation. The installation also says to “decompress [the package] from your hard drive or directly from the CD.” This is not quite correct since the package is not compressed—it's simply a tar archive. Despite these oversights, the installation is relatively straightforward.

Unlike many of the free packages available, Megahedron comes with oodles of documentation, all of it on-line on the CD and formatted in HTML. This is a nice bonus, since you can print the pages of interest from your browser. Most of the HTML documents print out as no more than 7 to 10 pages, which isn't too bad. Most impressive is the sheer amount of information provided.

The master Table of Contents contains links to five other areas: an introduction, a Quick Tour, an art gallery, the user's manual and sample source code. The Quick Tour provides a glance at some of the modeling, animation and procedural aspects of the interpreted language, called SMPL (Simulation and Modeling Programming Language). The tour is rather interesting. I found the train wireframe-animation particularly interesting, since most other tools I've seen don't offer such features (a notable exception is the rendribv program in the BMRT distribution).

The art gallery is not very impressive from an artistic point of view. The images present the modeling capabilities of Megahedron much better than the shading capabilities; future versions should explore the various shading capabilities provided by SMPL. This lack may be simply because the people who created the images are more technically than artistically oriented, but really useful 3D images should present a good blend of technical and artistic aspects. Some of the images from the art gallery are shown in Figures 1 and 2. Listings for the HTML code that goes with them are not printed in this article but are available by anonymous ftp in the file ftp.linuxjournal.com/pub/lj/listings/issue41/2282.tgz

Figure 1. Megahedron Cactus

Figure 2. Megahedron Roadster

An attempt was made to color-code the sample SMPL source, but the result is somewhat limited. There is quite a bit of code for experimentation purposes, although I have to admit I didn't run much of it.

The meat of the documentation is in the manual, a seven chapter document plus an Index, Glossary of Terms and SMPL Grammar Appendices. The seven chapters cover modeling and rendering aspects in fair detail. I'd like to see these two areas broken out into separate areas; Megahedron has merged the modeler with the renderer just a bit too much for my taste. There is also a good deal of material covering the use of shaders.