What Is Iray Anyway?

NVIDIA Iray rendering technology isn’t just for graphics pros.It’s a true engineering and design tool.

For many in the engineering field, the rendering tab in our CAD applications is a foreign environment. Rendering has been the domain of visual artists and those people who make Pixar movies, not for mechanical designers. In fact, at times, rendering has seemed downright daunting. But things are changing in the world of rendering, especially when it comes to CAD and design.

One of the biggest reasons for change has been the development of render engines and CAD-integrated rendering environments that are powerful and easy to use. One of the most powerful of these rendering engines is NVIDIA Iray.

Though the Iray rendering environment is included in a number of modern CAD tools (including SOLIDWORKS Visualize and Dassault Systèmes CATIA), engineers might not know how to use a render engine or that it has benefits beyond creating photorealistic images for the marketing department. But before we dive headlong into what rendering can do for an engineering workflow, let’s take a look at how the NVIDIA Iray rendering engine works.

What Is Iray?

A sample of materials available in Iray. (Image courtesy of NVIDIA.)

A sample of materials available in Iray. (Image courtesy of NVIDIA.)

Iray is a physically based render engine that simulates how light works in the real world. To create photorealistic images from CAD models, Iray samples how light interacts with materials and object volumes to create accurate reflections, caustics and other light phenomena. Though older render engines were able to do this kind of work in the past, users had to have a ton of computer graphics know-how and a knack for faking natural light to achieve good results. Iray simplifies the rendering process by using preconfigured light setups, drag-and-drop material controls and the ability to render an image quickly and in real time. No computer graphics degree necessary!

Although having preconfigured lighting environments is a huge benefit to designers, materials also play a critical role in creating photorealistic renders. To ensure that a render delivers the same properties that a viewer would see in the real world, Iray comes equipped with a verified materials library.

This library is a large set of common materials like glass, metals, plastic and more, all of whose properties have been finely tuned so as to be indistinguishable from their real-world analogs. By dragging and dropping any of these materials onto a model, engineers can ensure that the image produced by Iray will be as accurate as possible.

Another benefit that Iray offers users is its real-time rendering feature. In the past, designers would have to apply materials to their model, set up a lighting scheme, hit “Render” and then wait. And sometimes those waits could be long. Really long.

“Engineers shouldn’t wait an entire lunch break to get their renders,” said Phillip Miller of NVIDIA. “Rendering should be instantaneous and fun and serve as a tool to help a team make better design decisions.”

With Iray’s real-time renderer, designers can quickly change materials, lighting setups and other settings and see what their render will look like in a matter of seconds. No wait needed.

To achieve this result, Iray takes advantage of the thousands of cores that are packed into the GPU inside of a workstation. Once a change has been made to the render scene, a GPU is called into action, and it begins to calculate all of the lighting properties being created by the volumes, material and lights in a scene. What’s most impressive about Iray’s technology, though, is that the GPU can continue to refine a render into infinity, subtly turning a digital scene into an ever-more realistic image. While that type of calculation might not be necessary for many renders, when it comes to cutting-edge engineering, the more accurate the render, the better.

Rendering’s Use as a Design Tool

One of the most powerful examples of how rendering can enhance an engineering workflow comes from Honda.

Honda vehicle rendered using Iray. (Image courtesy of NVIDIA.)

Honda vehicle rendered using Iray. (Image courtesy of NVIDIA.)

Honda prides itself on creating quality cars that are both economical and stylish. Honda’s engineers are actually so dedicated to the details of their automotive designs that they’ve taken to using Iray as the gold standard for verifying what their cars will look like when they roll off the assembly line and into the real world. But aside from concentrating on the curvature of each panel, Honda uses 38 GPU servers to dig deep into its designs to discover designer flaws that most companies might miss.

What does that mean?

In one of their recent models, Honda’s engineers noticed that the housing in their brake lights wasn’t behaving as it should. When the brake light was engaged, the light from the brake light chamber would leak into other areas of the rear light housing, creating alight spillage that was unsightly and unacceptable. After noticing the light leak, Honda’s engineers took a deeper look at the problem area by creating a few more renders. With those renders in hand, Honda’s design team went back to its model and fixedits brake light housing flaw before it was shipped out for tooling. Because Iray accurately predicted the final results of a design,Honda was able to catch a flaw that could have cost the company tens if not hundreds of thousands of dollars in faulty parts and manufacturing delays.

Iray is not only a tool for visual artists and the marketing team. Its photo real rendering capabilities can be a powerful design evaluation tool that can save time and money while also leading to better designs.

Click here to learn more about NVIDIA Iray.

NVIDIA has sponsored ENGINEERING.com to write this article. It has provided no editorial input. All opinions are mine. —Kyle Maxey