Graphics Reference
In-Depth Information
2
V
glTF: Designing
an Open-Standard
Runtime Asset Format
Fabrice Robinet, Remi Arnaud,
Tony Parisi, and Patrick Cozzi
2.1 Introduction
This chapter presents work by the COLLADA Working Group in the Khronos
Group to provide a bridge between interchange asset formats and the runtime
graphics APIs. We present the design of glTF, an open-standard transmission-
format that bridges the gap between COLLADA and engines based on WebGL,
OpenGL, and OpenGL ES. glTF strives to provide a common foundation for
developers to eciently load assets into their engine. We discuss the format
itself, the open-source content pipeline tool that converts COLLADA to glTF,
andREST-basedcloudservices.
2.2 Motivation
Art assets account for a significant amount of the development costs of mod-
ern games and graphics applications. In 2003, the effort to provide a common
asset description format for content pipeline tools started at Sony Computer
Entertainment, and led to the COLLADA spec a few years later. Although the
compatibility of assets among modeling packages is now largely solved, engine de-
velopers still need to build their own content pipelines and transmission format
to produce optimized assets for their engines.
While work on COLLADA continued, the Khronos Group released new specifi-
cations for runtime APIs to provide hardware accelerated graphics. This includes
WebGL, OpenGL, and OpenGL ES. Even though the asset format and GL APIs
