What Is 3D Rendering? Complete Guide to 3D Visualization

3D rendering is all around us. From huge action movies to car commercials to previews of upcoming buildings or product designs, 3D visualization has become so widespread and realistic that you probably don’t even know it’s there.

In this introductory piece, Chaos’ Ricardo Ortiz explains the basics of 3D rendering, from the computational methods that create imagery to the artistic techniques that create great computer-generated (CG) content and its various uses.

What is 3D Rendering?#

Put simply, 3D rendering is the process of using a computer to generate a 2D image from a digital three-dimensional scene.

To generate an image, specific methodologies and special software and hardware are used. Therefore, we need to understand that 3D rendering is a process—the one that builds the image.

Types of 3D rendering#

We can create different types of rendered image; they can be realistic or non-realistic.

A realistic image could be an architectural interior that looks like a photograph, a product-design image such as a piece of furniture, or an automotive rendering of a car. On the other hand, we can create a non-realistic image such as an outline-type diagram or a cartoon-style image with a traditional 2D look. Technically, we can visualize anything we can imagine.

How is 3D rendering used?#

3D rendering is an essential technique for many industries including architecture, product design, advertising, video games and visual effects for film, TV and animation.

In design and architecture, renders allow creative people to communicate their ideas in a clear and transparent way. A render gives them the chance to evaluate their proposals, experiment with materials, conduct studies and contextualize their designs in the real world before they are built or manufactured.

For the media and entertainment industries, 3D rendering is fundamental to the creation of sequences and animations that tell stories, whether we’re watching an animated movie, a period drama, or an action sequence with explosions, ships from the future, exotic locales, or extraterrestrial creatures.

Over the past few years, the evolution of computer graphics in these industries has replaced traditional techniques. For example, special effects are being replaced by visual effects, which means stunt people no longer risk their lives in car crashes.

In advertising, I would dare to say that 90% of automotive commercials are CG—or even more. In the architecture industry, many traditional techniques to create representations, such as scale models, have been replaced with photorealistic imagery to ensure we can see exactly how something will look once it’s built.

Accelerating processes, reducing costs and the demand for better quality results have helped technology evolve. Hardware is more powerful than ever and the switch to CG was inevitable.

How is a 3D rendered image generated?#

Two pieces of software, with different characteristics, are used to computer-generate images and animations: render engines and game engines. Render engines use a technique called ray tracing, while game engines use a technique called rasterization—and some engines mix both techniques, but we will talk about that later on.