Wednesday, June 5th, 2024 Posted by Jim Thacker

ASWF, Adobe, Autodesk launch OpenPBR 1.0

Originally posted on 3 August 2023, and updated with details of the 1.0 release.

VFX standards body the Academy Software Foundation (ASWF) has launched OpenPBR, a subproject of MaterialX, the open material standard it maintains.

Created by Adobe and Autodesk with “guidance from the MaterialX Technical Steering Committee”, the open-source shading model supersedes the Adobe Standard Material and Autodesk Standard Surface.

OpenPBR is intended to increase interoperability of materials between CG software, with any tool that supports MaterialX supporting OpenPBR automatically.

Unifiying Adobe and Autodesk’s internal material standards
Currently, Adobe and Autodesk maintain separate, but parallel, technical specifications for 3D materials: the Adobe Standard Material and Autodesk Standard Surface.

Both are intended to streamline look development by making it possible to transfer materials between applications, with materials displaying near-identically in each app.

Both also draw on many of the same sources, including Disney’s Principled Shader and Allegorithmic’s PBR shading model, with Adobe even citing the Autodesk Standard Surface as an influence.

However, at present, both are really only supported in the developers’ own software: in the case of Autodesk Standard Surface, Arnold, 3ds Max and Maya, for Adobe Standard Material, the Substance 3D tools.

Automatically supported in any application that supports MaterialX
OpenPBR should unify the two models, making it possible for materials to display consistently across Adobe and Autodesk software.

In fact, materials should display consistently in a much wider range of apps, since OpenPBR is a sub-project of open standard MaterialX, supported in a range of CG software, including Houdini, RenderMan and UE5.

MaterialX materials are also supported in Blender via AMD’s USD Hydra plugin.

A demo shaded using OpenPBR and rendered in Arnold for Maya by Nikie Monteleone.

Updated 6 November 2023: OpenPBR has been released publicly. The initial release, OpenPBR 0.2, includes the specification for the OpenPBR Surface shading model.

Updated 5 June 2024: OpenPBR 1.0 has been released.

The full release introduces a reference implementation for OpenPBR within MaterialX, “meaning that tools in the MaterialX and OpenUSD ecosystem will automatically support OpenPBR” without developers having to build their own implementations.

Licence and system requirements
The OpenPBR specification and source code for the reference implementation are available on GitHub under an open-source Apache 2.0 licence.

On the GitHub repository and on Adobe’s blog, the specification is also referred to as OpenPBR Surface.

Read the Academy Software Foundation’s blog post announcing OpenPBR 1.0

Download the specification and reference implementation for OpenPBR from GitHub

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