Things Heat Up As Nvidia Illustrates the Power of Physically-based Rendering
Greg Estes
March 23, 2015

Things Heat Up As Nvidia Illustrates the Power of Physically-based Rendering

Seeing is believing. At last week’s GPU Technology Conference, Nvidia made some pretty bold product announcements, among them an updated product road map for physically-based rendering. 

To give attendees a glimpse of what their announcements meant, Nvidia presented the "Death Ray" demo, which looked at problematic real-world structures and showed how interactive, physically-based rendering saves time and uncovers design flaws. 

What’s cooking in pro graphics: How real-time raytracing can avert a real-life “death ray”

You know something’s awry when your building starts melting nearby cars.

London’s year-old 20 Fenchurch Street tower is a stunner. But the same curved glass that gives the 37-story tower the nickname “The Walkie Talkie” also has a knack for concentrating sunlight.

The result: a hot spot that melted part of a nearby black Jaguar XJ and cooked shampoo in a local barbershop. It’s even been used to fry eggs.

Such “death rays” are growing problem, thanks to a new generation of glass-sheathed buildings with radical computer-designed curves. Those curves reflect – and concentrate – light in ways that have been hard for designers and engineers to predict. Until now.

The demo at Nvidia’s annual GPU Technology Conference taps into the power of GPUs to show how London’s fifth-tallest building came to be called the “Fryscraper.”

A new generation of glass-sheathed buildings with radical computer-designed curves have created some unexpected challenges.

And Iray We Go

Rendering – the process of turning a digital model into an image on a screen – isn’t new, of course. Nor is raytracing, which tracks the way beams of light interact with objects in their environment. What’s new is how Nvidia’s Iray raytracing technology takes advantage of GPUs to render detailed models in real time.

The result is revolutionary: Rather than relying on technology that takes hours to create a single, static image – a snapshot – designers, using Iray, can view rich digital images as they work. And they can see how light interacts with their design over long stretches of time – as the sun moves across the sky at different times of the day and year – rather than just a moment or two.

Nvidia is putting these tools within reach of every designer with plug-ins that will build this capability into the most popular design tools. It’s a move that’s sure to save time. And, potentially, trouble.

Avoiding a deadlier death ray

In fact, Nvidia found the Walkie Talkie building’s solar glare could have been worse. Alter the building’s curves just a nudge or two, and it could create a beam hot enough to melt lead.

Such powerful simulations build on technology the company first demonstrated at last year’s GTC. Nvidia showed, together with Honda, the first interactive visualization of an entire car.

The demo didn’t just spin around a digital prototype. It showed how a person could section the vehicle and peel off layers to view the innards of the car, right down to the silver Accord’s electrical wires and seat springs.

Technology like this promises to solve a huge number of common design problems. And some that aren’t so common.

Challenges of modeling light

Take 20 Fenchurch – its glass curves create a spot where the temperature can rise to almost 200 degrees Fahrenheit. Or the Vdara Hotel, just off the Las Vegas Strip – its concave glass facade creates temperatures by the pool hot enough to melt plastic. Or LA’s extravagant Walt Disney Concert Hall – it heated up nearby condos, driving residents to draw their shades and run air conditioners.

None of this is the work of mad scientists or Bond villains. The structures were created by architects and engineers who lack the tools to predict how their designs will interact with the world around them.

In the past, modeling reflected light has been a time-consuming procedure. It’s usually reserved for presentations of near-final designs. And designers build those presentations around specific lighting conditions. They’re snapshots, not simulations.

Nvidia's Iray technology can model light in ways that just weren't practical before.

Introducing Quadro M6000 graphics cards

Nvidia’s new Iray 2015 rendering technology changes that. When paired with the new Quadro M6000 graphics card – the world’s most powerful GPU – Iray 2015 models the way light bounces around a scene as design teams tweak their models.

And rather than having to wait hours to create photorealistic images that are ready to put in front of a customer, designers can just add more GPUs to create higher-resolution models in an instant.

With eight Quadro M6000 GPUs in the just-upgraded Quadro Visual Computing Appliance (VCA), the level of interactive photorealism is stunning.

Put ther VCA in a data center, and design teams can call on its rendering power when and where it’s needed. Every Nvidia Iray product will include the ability to stream rendering from machines running the Iray Server software.

Same tools, new rules

All this technology works with the tools designers already use. Nvidia is making Iray accessible to millions of users with add-ins for popular 3D creation applications, including Autodesk’s 3ds Max, Maya, and Revit, McNeel’s Rhinoceros, and Maxon’s Cinema 4D.

With this new generation of prototyping tools, designers and engineers no longer have to build detailed physical models. Or create movies of rendered objects. Instead, designers can see their work in real time.

That can save months. Or years. And even save a few Jaguars from the next “fryscraper.”