Archive notice: This article was originally published on May 10, 2019. Links and embedded videos are preserved as part of the historical record.
Dylan Sisson (Technical Artist, Pixar) was also at FMX 2019 last week and announced the release of RenderMan 22.5 there in several sessions, among other things. Anyone who could not be at FMX can once again view a short summary of 2019 here. In his talks, Dylan also provided insights into the Toy Story 4 film, as well as new information about the development of Pixar’s XPU variant (CPU & GPU) and USD.
Overview of the New Features
The biggest new features of the RenderMan 22.5 update include, among other things:
- The new RenderMan for Houdini plug-in
- Adaptive Sampling improvements
- Interactive Displacement & Volume Density
- OSL acceleration in OSL Networks
RenderMan for Houdini
Houdini users can rejoice: Pixar’s completely rewritten RenderMan for Houdini plug-in (RfH) supports the latest workflows in RenderMan. The improved integration includes, for example, interactive modeling, shading and lighting and more.
The most important supported functions include…
- Geometry: Curves, Points, volumes, Mesh and more
- Interactive editing of geometry, lights, cameras and light filters
- Material Builder shader networks with RenderMan shading nodes
- Rendering in Houdini’s native mplay framebuffer and Renderview
- Texture Manager: Automatic texture conversion into Pixar’s texture format.
- Preset Browser: Import and export shaders, light rigs and HDRI maps
- You can view a complete list of the RfH features here.
More Speed with OSL!
As can be seen in the following examples from the Kitchen Challenge, there is a significant performance boost compared with earlier versions. The first pixels for the older version 21 appear after around 21.5 seconds; for RenderMan 22.5, this happens after only 5 seconds.
Version 21.0 – First Pixel Test
Version 22.5 – First Pixel Test
https://vimeo.com/335448578/115c6945bb
Although the acceleration occurs only in OSL Networks, most RFM nodes are C++ based. As soon as these are replaced by OSL nodes, greater performance improvements can be detected here. Following collaboration with Intel, RenderMan 22.5 offers new hardware acceleration for CPU-intensive OSL processes. In scenes rendered on Intel Xeon CPUs that support AVX2 and AVX-512, an average increase of 15% is said to be achievable. According to our information, this is also intended to apply to AMD processors as long as the respective processor supports AVX2.
Toy Story 4 Use Case
With Toy Story 4, Pixar has the first major film that is and was rendered with the new version. At FMX, we saw initial tests of the improved adaptive path-tracing methods in RenderMan 22.5. According to Dylan, more than 44,000 lights are integrated into the following scene and coordinated with one another. With the new technique, lights are intended to ensure correct light values relative to one another and overall more realistic lighting. Take a look at the test render here:
https://player.vimeo.com/video/335417616
As an example of the use of the new Houdini plug-in, the responsible Pixar team did not simply make themselves scarce: To create a more realistic environment, a tool was created that simulates the formation of dust on surfaces in enclosed spaces. You can view the result in the following images:
Preview: The Future with XPU
The new future hybrid model – RenderMan XPU – is currently still under development at Pixar. The new architecture is intended to make it possible to use either the CPU, the GPU or a combination in the same frame when rendering. According to Dylan, however, no release can yet be promised for this year. The latest major XPU presentation took place at GTC 2019, which you can view online here.
In return, however, Pixar showed us a new preview clip at FMX 2019 in which the XPU version is used for a classic look-dev character. The rendering algorithm uses OSL exclusively here, no textures. OSL allows the exact same shader code to be executed on a CPU and a GPU. The results already look promising so far – but to make a proper judgment, we still have to wait until the first beta versions roll our way.
USD in RenderMan
Universal Scene Description (USD) is Pixar’s open-source file format and API, used to describe and standardize CG scenes and data for pipelines & workflows. The format is now already used in many studios – alongside Pixar, for example, at MPC, Luma Pictures and ILM. A new release on GitHub is planned for the coming month (June 2019), which enables support for third-party tools based on USD’s Hydra imaging framework. By the end of the year, it is also intended to be possible to render USD directly in RenderMan. Pixar will probably provide more information about this at SIGGRAPH 2019. You can find further details about USD and Hydra here.
RenderMan 22.5 Availability
The new release is available now for Windows 64-bit 8.1+, CentOS/RHEL 7.2 Linux and macOS 10.12 on the official website here. There have currently been no changes to pricing. Anyone who wants to test the renderer or is a student can download a free non-commercial license.
Further information: Go to the RenderMan 22.5 release notes
