Issue link: http://digital.copcomm.com/i/1144162
s u m m e r 2 0 1 9 c g w 4 9 tures, and colors to be defined in a portable, application-independent fashion. For look development, however, there was no existing standard that could represent the rich, networked materials that artists were authoring in tools such as Foundry's Mari, Allegorithmic's Substance Designer, and Foundry's Katana, and these assets were greatly restricted in their usage and compatibility over time. As a potential path forward, the Unified Asset team was drawn to an early, internal specification named MaterialX, which had been pro - posed by Smythe in the previous year. This technical proposal seemed like an ideal starting point for a new, unified mate- rial standard, and Stone began working with Smythe to extend the specification to cover real-time as well as off-line rendering. Work began immediately on a C++ and Python codebase for common functionality such as material import, material export, and the editing and traversal of material graphs. The first show to leverage this new code - base was Transformers: Age of Extinction, for which MaterialX was integrated with Lucasfilm's look-development framework in Mari. This gave artists the ability to transfer material content between individual material layers and also between geometries. These new features proved popular and gave Lucasfilm a sense of how experienced artists could use fine-grained material transfer functionality in new and creative ways – as well as give them valuable experience with the new codebase in a complex production environment. By the time Star Wars: The Force Awak - ens entered pre-production in late 2013, Lucasfilm was ready to test MaterialX as a canonical material format for the entire show, from the initial prototyping of mate- rial libraries to the end-of-show archiving process. For the first time, libraries of Ma- terialX presets based on Lucasfilm's new unified shader were authored in Katana and used for painting in Mari, with com- pleted material assets being archived as networked MaterialX files in the Star Wars franchise digital backlot. This general ap- proach has been used on all subsequent ILM shows, with support for additional tools and pathways being developed in the years that followed. In parallel, Lucasfilm began leveraging MaterialX as a vehicle for transferring mate - rial content from the ILM CG visual effects pipeline to the real-time technologies pow- ering interactive experiences such as Star Wars: Trials on Tatooine. This transmedia sharing of materials took a significant step forward on Rogue One: A Star Wars Story, for which three shots of K-2SO were rendered in a custom build of Epic's Unreal Engine 4. Rogue One production leveraged MaterialX for the transfer of materials between the film and real-time pipelines. A similar material transfer approach was used by ILMxLAB and The VOID on the real-time immersive experience Star Wars: Secrets of the Empire. MaterialX was also used for production of the Millennium Falcon attraction for Star Wars: Galaxy's Edge at Disney Parks. THE PATH TO OPEN SOURCE Lucasfilm's previous open-source projects, OpenEXR (2000) and Alembic (2011, with Sony Pictures Imageworks), had been important steps forward for production computer graphics, and consideration for an eventual open-source release was factored into even the earliest days of Ma - terialX development at ILM and ADG. Only by making MaterialX an open standard and codebase would it be able to evolve along with the larger industry, allowing develop- ers to embed support for MaterialX in new tools and pipelines as they are built, and to contribute improvements and ex- tensions as they are needed. IN ROGUE ONE, K-2SO WAS RENDERED IN A CUSTOM REAL-TIME ENGINE, WITH MATERIALX USED TO TRANSFER MATERIALS BETWEEN FILM AND REAL-TIME PIPELINES.