NVIDIA Iray has long been part of CAD software such as Autodesk Maya and 3ds Max. Iray was introduced to sit alongside mental ray, the well-known rendering package that seamlessly integrates with supporting Autodesk products. With a large number of parameters, mental ray required a level of setup that some users may struggle to incorporate into their workflow, especially designers who just want to design and not worry about render settings. Iray changes all that with a simple interface to aid the designer. It is a physically based ray tracing renderer with accurate lighting and materials based on real world values. Rendering is simple with little to no setup using either the CPU, GPU or both.
Iray has been coupled with software applications for some time which meant updates and improvements came during the infrequent service packs. This allowed other alternative renderers to excel as they had the freedom to update as and when required, this quickly left Iray outdated. Now for the first time ever NVIDIA are offering their new Iray+ renderer as a separate plugin for supporting CAD software. NVIDIA can now deliver their latest technology smarter by offering rapid feature exposure and build a direct relationship with their customers through online forums, something they have been unable to do fully whilst being kept under Autodesk supervision.
Iray+ is currently available for Autodesk 3ds Max with support for Maya, Revit and Rhino to follow. It will cost $295 per year giving the user a single license which can be applied to a workstation or a node as well as transfer between the different supported CAD software. Each additional workstation or node would require an additional license, however there are no restrictions on the number of processors. Therefore a multi GPU workstation or node will only be a single license. Paying $295 a year for something that was previously part of a software package may not appeal to some users initially but it does however fall in line with what other renderers have already been offering for some time whilst building a loyal and respectable fan base. This is something NVIDIA wish to do and what they bring to the table with the Iray+ is impressive, so certainly worth the annual fee.
Some of the main features include render queuing and streaming using Iray Server, as well as a large library of NVIDIA certified materials known as vMaterials that are built using NVIDIA’s latest Material Definition Language (MDL). These are physically based materials that can be shared between supporting software applications. There is also Light Path Expressions (LPE) which gives the ability to save out individual light contributions from the final render and composite them separately in post-production. This gives the user full control over adjusting each light independently.
NVIDIA offers a 90 day free trial of Iray+ with no restriction which is easily enough time to get stuck in and have a play and there are a couple sample scenes as well to get to grips with. We had the opportunity to test an early version of Iray+ inside Autodesk 3ds Max using an NVIDIA Quadro M5000 professional workstation GPU which has 2048 CUDA cores and 8GB of GPU memory. Here are our thoughts on some of the key features.
Iray+ has two renderers, Iray+ and Iray+ Interactive. The Iray+ renderer delivers the most accurate results and is intended as the production renderer. Iray+ Interactive provides fast feedback via ActiveShade when adjusting lighting, materials and geometry. This offers the perfect preview in no time at all thanks to its advanced approximation algorithms. Both renderers work to clean noise as quickly as possible reaching either the set number of passes or minutes per frame.
The purpose of Iray+ is to deliver physical accuracy. Realistic photometric lighting and sky systems combined with NVIDIA’s Material Definition Language (MDL) delivers realistic imagery with a real-world approach to materials, lighting and exposure. For those who wish to break away and deliver an individual style, there are simple to use tone mapping controls built into the Iray+ UI. Here the user can adjust exposure, highlights, shadows, saturation and white balance. Tone mapping also works with Iray+ Interactive and updates in real time which is great for getting that final look before committing to production. Moving over to Iray+ from interactive mode is a simple switch with Iray+ Interactive being a close representation of the physically accurate production result.
A new and exciting feature from NVIDIA is Iray Server. It has two main features, queuing and streaming.
Queuing enables the user to send render jobs to Iray Server and continue working, allowing the user to render them later on using the same workstation or send them to another render node or NVIDIA VCA. The queue interface can be accessed via a web browser and there are options to control and view render progress as well as add and remove users with permissions. The UI is clear and informative and can be accessed anywhere on the network making the managing of jobs a simple task.
Streaming allows the user to continue working locally on a client machine without disruption whilst the rendering is processed by an external machine running Iray Server. It is delivered through ActiveShade leaving the local processing power of the client machine untouched. An NVIDIA Quadro GPU is required to be present in the server machine to run streaming but any NVIDIA GPU can be used in the client machines and there is support for multiple GPU architectures.
Iray+ comes shipped with access to over 200 vMaterials that have been checked and certified by NVIDIA for their physical accuracy. These materials are based on MDL which forms the building blocks for creating real world materials. A vMaterial is made up of individual layers that are flexible by design and consist of either a core base layer for a material or an emissive object layer for things such as a light bulb or TV screen. Surface, coating and decal layers can be added on top in any order at a multitude of 16 times. When creating a new material from scratch there are base pre-sets for various material types such as woods, metals and plastics. The concept of having a material library is something users have requested from various leading rendering software packages. Therefore to have a library to start with and the option to build from scratch does cater for both the designer who wishes to use pre-set materials for speed and the material enthusiast who wishes to be creative and tailor materials to the project.
One feature we really liked is the procedural dust, dirt and scratches layer. It is easy to use and adds that extra realism to any material. All vMaterials are setup to use real world scale so it minimises setting up mapping coordinates which speeds up the workflow even further. MDL is designed to be a standard format that can be used across various design software as well as across multiple rendering packages. Chaos Group V-Ray will support MDL which gets the big thumbs up from us as sharing materials between rendering packages has never been easy.
There is support for 3ds Max standard and photometric lights but Iray+ also comes with its own set of lights that deliver further physical accuracy. These include artificial lights with photometric support and natural lighting simulation either through the Physical Sky or Image Based Lighting (IBL). IBL comes with some helpful tools such as ground shadow and reflection, so there is no need to add an extra surface to catch them. Adding a HDRI is simple and there is an option to preview the HDRI in the viewport as a spherical or hemispheric environment, a nice touch as it avoids having to guess where the main light source is coming from making it easy to position the HDRI. Another useful feature is the active environment light switcher in the rendering settings. This is useful if multiple lighting setups are required for day and night or switching from a basic physical sky setup to a more advanced IBL setup. The user can switch between them via a handy list.
There is currently no support for the latest 3ds Max 2016 physical camera and the accompanying exposure controls, it already works seamlessly with Chaos Group V-Ray so to have the same support from NVIDIA Iray+ would allow for a much easier transition between rendering software and from user to user.
As with previous versions of Iray, Iray+ is well integrated with 3ds Max giving the user a familiar interface to work with and most features are supported as well as Iray+ offering some of its own without overcrowding the user interface. Iray+ is built for the designer, so less time is spent on render settings and more time spent on the design process. Iray+ delivers quality results with minimal effort and there are well-placed tools that make the workflow that extra bit smoother. Iray+ focuses on the critical components of a renderer that a designer needs which are interactivity, materials and lighting.