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glTF

Fabrice Robinet

COLLADA Working Group Chair.

Patrick Cozzi

Analytical Graphics Inc, and University of

Pennsylvania.

graphics library Transmission Format https://github.com/KhronosGroup/glTF

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Overview

•status

•motivations

•design principles

•glTF pipeline

•scope

•early support and adoption

•demos

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Status

•COLLADA Working group initiative.

•Work in progress - Not a ratified specification yet.

•Community feedback welcomed on GitHub.

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Motivations

•Bridge the gap between 3D formats and GL based APIs.

•Reduce duplicated effort in content pipeline.

•A common format for contents providers.

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Design principles

•Streamline rendering: size, speed and ease of implementation

•Offload processing from runtime.

•Maps well to GL APIs and Typed Arrays.

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Delivery Author Interchange

glTF Pipeline - overview

API

Maya

Blender

..

COLLADA glTF

OpenGL/ES

WebGL

OpenGL

COLLADA2GLTF

Converter

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glTF Pipeline - overview

OpenCOLLADA Compression

COLLADA2GLTF C++ Library

Rapidjson

COLLADA2GLTF command line tool

Rest3D transactions & access to 3D assets

COLLADA2GLTF Delivery Author Interchange API

Maya

Blender

..

COLLADA glTF

OpenGL/ES

WebGL

OpenGL

Converter

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glTF Pipeline - COLLADA2GLTF

• Triangulate

• Unify indices

• Split meshes

• Generate shaders

• Axis up conversion

• Minify shaders

• Flatten hierarchy & combine meshes

• Convert images

• Compress meshes

• Interleave vertices

• ... Suggestions welcomed !

Mandatory transformations

Planned optimizations & transformations

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Scope

•1.0

- node hierarchy with geometry, materials/lights (shaders), and

cameras

- Key-frame animations

- Skinning

•Mesh compression discussions engaged with partners.

•Target feature complete draft for late summer 2013.

•Community feedback welcomed on GitHub !

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Early support and adoption

•Montage.js: http://montagejs.org & https://github.com/montagejs/

Implementation and JS API on-going.

•Cesium: https://github.com/AnalyticalGraphicsInc/cesium

•Sample Three.js loader in glTF repo:

https://github.com/KhronosGroup/glTF

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Demos

•Model Viewer: Fabrice Robinet.

awesome cloud shader by Iñigo Quílez

•WebLVC Viewer using Cesium: Patrick Cozzi. http://video.weblvctestbed.com/cesium-VR-TheWorld/Apps/SimSpy/index.html?wsPort=80

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Thank you - See you on GitHub !

Specification : https://github.com/KhronosGroup/glTF/blob/master/specification/README.md

Converter: https://github.com/KhronosGroup/glTF/wiki/converter