PresenZ: Volumetric VR without a game engine

PresenZ: Volumetric VR without a game engine
James Batchelor

By James Batchelor

August 18th 2016 at 2:53PM

Nozon and Chaos Group on its ambitious new virtual reality technology

Two companies have teamed up to create a form of virtual reality that artists will be able to use without the need for a comprehensive game engine.

PresenZ is the brainchild of post-production specialist Nozon and computer graphics technology firm Chaos Group, and enables the create of "pre-rendered volumetric VR". The plug-in was showed off at this year's SIGGRAPH and allows free movement without the fear of motion sickness.

Watch the video below to find out more:

PresenZ for V-Ray from NOZON 3D/Vfx on Vimeo.

We spoke to Matthieu Labeau, chief commercial officer at Nozon, and Lon Grohs, business development manager at Chaos Group, to find out more about the technology.

What is volumetric VR? How does it work?
Labeau: Volumetric VR stands for content created in CG or captured with a camera rig and that allows for six degrees of freedom at playback time. The user can move freely inside the images.

Some companies focus on the capture, we focus on pre-computed rendering and on the format. We can easily integrate the captured content in our format.

Where did the idea originate and how did work begin on this?
Tristan Salomé, is at the origin of the project. He is one of the founders of Nozon.

He graduated as biochemical engineer then worked on AI and then VR in 1990s – even though at the time, the promises of virtual reality were already there, the hardware wasn't mature. The headsets weren't up to scratch and the graphic units were not fast enough. As a result, most of the users were sick inside the simulations.

By linking PresenZ to V-Ray, game devs will be able to blend production-proven, photorealistic rendering that's been honed across a number of industries.

So Tristan turned to pre-computed images, starting Nozon 18 years ago as a 3D animation and visual effects. Since then, we made numerous high-end commercials and two animated feature films.

At the beginning of 2014, his attention was drawn by the Oculus Crystal Cove prototype, because based on the technical specifications it seemed that they had solved the main problems he'd had with VR hardware in the '90s. So, based on his past experiences, he wanted to create something at the crossroad of virtual reality and movies.

What is each company bringing to the table? How does the collaboration work?
Labeau: PresenZ allows V-Ray users to produce volumetric renders directly from V-Ray. They don't have to change their pipeline and can reuse assets. Nozon provides the plug-in and did the porting. But the technology is not stand alone and needs a ray-tracer to work. We chose to work with V-Ray for different reasons: the reputation of the company, the dynamism of its community of users; the interest that Vlado and Christopher showed towards our solution since the beginning, the support we've got from Chaos Group from the first meeting until now. 

Grohs: When we saw what Nozon was doing with PresenZ, we knew this was something our users would love. By linking PresenZ to V-Ray, game devs will be able to blend production-proven, photorealistic rendering that's been honed across a number of industries (VFX, architecture, advertising, automotive), with an incredibly simple way to add VR movement. Since every VR application doesn't require a game engine – marketing, for instance – this should open up more avenues for artists who want to create high-quality VR with movement with the traditional 3D toolset they are used to.

How does positional tracking overcome the danger of motion sickness for VR users?
Labeau: Motion sickness in VR is caused by the discrepancy between the motion that the user experiences in VR and what the vestibular system registers from the real physical motion. A solid tracking that matches VR motion with the real movements of the user is essential to overcome motion sickness. This is why 360-degree movies without tracking cause motion sickness while watched on a VR headset. 

We are also focusing on the content. Content is as important as the hardware to have a comfortable experiences. We have tested a lot camera movements at Nozon studios. We are advocating the use of teleportation more than translations in VR. We see now that  more movies/experiences as games are using teleportation.

How does PresenZ go beyond the visual limitations of VR rendered through a game engine? What holds the engines back?
Labeau: They are limited in terms of image quality and scene complexity, basically they look like a video game. It's directly linked to the real-time rendering, which means that the images have to be computed at the same pace as they are displayed.

In Virtual Reality, this translate to about 5 milliseconds per image. Compared to the several hours of computation taken by a single image in a Pixar movie, you can easily imagine the difference in quality and scene complexity that you can render. 

For filmmakers and designers, it also involves a complete change in the movie and image making pipeline. You will have to learn new tools, get new software and acquire some specific Know-how to handle real-time graphics properly. 

You mention the potential for 360-degree movies, but what are the gaming implications here? How will this benefit games developers?
Labeau: We're also working on integrating the PresenZ player as a plugin in video game engines. Realtime graphics can be mixed with PresenZ. For instance an openGL object  going behind an element in the PresenZ scene will be occluded.

So by incorporating PresenZ inside a game engine, we'll be able to have representation of your own avatar or others viewers avatars, or add some interactive objects inside the movie. The logic of the game engines could also be used to branch between different movie clip depending on the user actions.

Or the opposite can also be done, game developers will be able to integrate, for example, backgrounds  in their scenes in order to lower to load on the GPU and reach more photorealism.

Since every VR application doesn't require a game engine – marketing, for instance – this should open up more avenues for artists who want to create high-quality VR with movement with the traditional 3D toolset they are used to.

Why is it important to equip artists with VR tools, as well as games developers?
Labeau: VR is an incredible media, but not only for gaming. B2B firms can profit deeply from this media: architecture, design, health, entertainment in general etc. I'm not saying anything new here when I say that a new media needs tools that are adapted to it. We are working on making PresenZ part of an entire pipeline dedicated to VR and plugging in existing tools at different levels (3D creation, rendering, compositing). The goal is to make high fidelity VR as easy to create as possible.   

The technology is currently in beta. What’s the next step for PresenZ?
Labeau: The next step will be to fully integrated in V-Ray and included in the V-Ray package. Regarding development of the technology itself, we are working on temporal compression that reduce the size of the files from 500 Mb a second to 30Mb/sec; on a plugin to video game engine, on compositing tools etc.