What is 3D Rendering?

3D rendering is the form of digital art that I do. I wrote this quick primer on it a few years back, but if you have an hour to kill, I also have a youtube video that covers all the fundamentals.

Overview

Rendering, also called “digital rendering” or “3-D rendering” is a new form of art made possible by the existence of computers. Essentially, it is the creation of two-dimensional artwork using a computer to generate an image. The artist describes the scene in a way that the computer can understand. The computer then uses that description to simulate a 3D reality from which it takes a virtual snapshot. That snapshot can then be left in digital format or be printed out by the artist.

Modeling

The first step in creating render art is the creation of a virtual model. This is analogous to sculpting a model from clay in the real world. The artist begins with a virtual lump of clay, often a sphere or cube, then molds model by stretching it, twisting it, and adding on to it. The process can get rather elaborate. Model making software can cost thousands of dollars, but there are some free applications, such as Blender 3D (which I use) that are quite capable of producing high end models.

Skinning

A virtual model really only defines a shape. Generally, modeling software will let you define how the surface of that model appears (color, texture, reflectivity, etc.) but, more complex models call for skinning. Skinning is the process of creating of what is known as a UV Map. A UV Map is a special picture file that can be wrapped around a model to give it a surface. It’s sort of flattened version of the model analogous to the pattern one uses to cut material for clothing. Modeling software will help to create the UV Map, but I use image editing software, such as Photoshop or GIMP, to actually color in the UV Map.

Rigging

Certain complex models might call for something known as rigging. Rigging allows the artist to reposition certain parts of a model rather than having to remold a whole new one. For instance, if I create a model of a human form, I may want to be able to reuse that model in different poses. Rather than shaping a new model for every pose, I can rig a single model virtual skeleton. I assign groups of polygons to certain “bones” and then define how those bones can move in relation to one another.

Layout

The layout stage of rendering is where the artist defines the spatial relationships between objects in a scene. The objects are models created in the prior steps. This step also includes defining the light sources for the scene as well as atmospheric aspects of the image such a haze and fog.

Rendering

This is the step that is handled by the computer (or network of computers – called a render farm). The computer uses advanced mathematical algorithms to simulate the effects of the light and atmosphere upon the objects set up during the layout phase. This can take anywhere from a few minutes to many days depending upon the complexity of the screen. The final product is a CGI, computer generated image, usually in the form of a bitmap or JPEG file.

Post Production

This is the part that would be more familiar to traditional artists. In the post production phase the image is loaded into image editing software such as Photoshop, Corel Painter, or GIMP. The artist then makes adjustments to the image ranging from simple color changes to painting new parts.

Printing

The final step in the rendering process is the production of the physical work of art. This is done by using any number of computer printers. They can be a simple standard inkjet printer printing on photo paper or monstrous wide format printer printing on canvas. I prefer the latter. High quality prints on canvas are often called giclées, though now, most places just call them canvas prints.

Hope this primer helps a few folks!

Daniel

P.S. Don't forget to check out my gallery.