With the emergence of powerful next-generation platforms such as PS2 and X-BOX, game artists have been given unprecedented power to create realistic manifestations of their creative vision. No longer do characters, vehicles and other game objects and environments have to be represented by blocky, low-resolution geometric parodies of the desired design. Ultra-high poly-counts and adaptive tessellation of spline-based models allow for highly sophisticated organic surfaces. Real-time reflection, specular and environment-mapping allow light and reflection to perfectly describe every subtlety of an object's shape. We are rapidly approaching the point where sophistication of form won't be lost in the translation to real-time models. Rather, the lack of subtlety in how form development is approached will begin to mark the difference between good design and bad, much as it does in the product and automotive industries. More than ever before it behooves the designer to truly understand the three-dimensional nature of the forms he or she is creating, and to properly communicate to whomever may be executing the design the important relationships, resolutions and proportions of form that they are instinctively instilling into their designs.
The goal of this paper is to give designers the ability to think of organic three-dimensional shapes in a structured way, rather than as abstract "blobby" form. As well, an understanding of how form affects light and reflection, and how to apply that knowledge to drawing, will be covered. Armed with this knowledge, artists should be better equipped to control the forms in their designs, illustrate them accurately from any number of angles, and communicate the underlying structure (and thereby a way of approaching them) to whomever (including themselves) may be tasked with making the design 'real'.
To sum up, this article could be called: "Making rounded shiny things that look good."
Describing Organic Form
As this is for a relatively "advanced" audience, I am not going to get into the basics of defining volumes or proportion. I am also not going to deal with simple geometric forms, such as planes, or cubes, or cylinders, except in terms of how they help us to understand more complex forms. This article will focus on organic surface: the type of surface that cannot be easily described mathematically, or drawn readily with rulers and circle guides. The type of surface that is shaped intuitively by the free flowing hand and controlled by the eye.
There are many methods of describing organic form in general terms: simplifying the shapes to intersecting stretched spheres; starting with primitives and then 'softening' them into more 'rounded' shapes; stringing together a series of evenly-spaced two-dimensional cross-sections. The first two are useful to describe the volume of the form, but lack enough sophistication to describe the surface. The last is of obvious use, but assumes an intimate knowledge of the surface in order to generate it in the first place. It is no coincidence, by the way, that all of these methods have been used in the past in 3-D modeling. Needless to say, there are many others.
The approach that I prefer to use is to concentrate on the surface. When broken down, any organic form can be described as a of combination of convex and/or concave surfaces, either intersecting to form edges, or blended together through tangential transition surfaces, themselves either convex or concave. Breaking down a given surface becomes a process of identifying where one surface ends and the next begins, and then describing the character of those individual surfaces. And when it comes to describing things, the first thing you need is a vocabulary.
As a means of conveying the understanding of form, I will be drawing on some of the vocabulary that designers, primarily in the automotive industry, have been using to control and communicate sophisticated organic form for the past few decades. Car bodies have arguably the most sophisticated surface development of any man-made object, and present an extreme case of highly controlled, yet difficult to describe forms. Geometric forms are simple: they can be described in very precise mechanical terms. Completely natural forms, such as animals or plants, are more difficult, but allow for natural imperfections, asymmetricality and irregularity. Manufactured organic form such as automotive styling, on the other hand, is at once free-form and rigorously precise.
In order to communicate design intent between stylists and clay modelers, automotive designers over the years have developed a language of form and corresponding terms, much of it borrowed in turn from older disciplines such as cabinetmaking, sculpture, shipbuilding and coach-building. This short-hand makes it easier for design teams to communicate succinctly and accurately what a form is doing, without resorting to vague description in the vein of : "it's sort-of flat, but not quite, with more of a roundness at the end". These terms also describe fundamental elements of three-dimensional form, such that the use of them enables the designer to break complex surfaces down into controllable elements and intersections.