glTF Reader

The glTF Reader provides access to visualization data stored within a particular glTF file. A file does not need to have a particular extension to be read correctly by HOOPS Exchange; however, the file extensions of glTF files that you can expect to be loaded by HOOPS Exchange are:

• .gltf

• .glb

Our readers are updated to the latest released version within 90 days of the release of the authoring software. You can see the exact version supported in the current release here.

Physically-Based Rendering Material

As of version 2019 HOOPS Exchange now supports physically based rendering (PBR) materials with A3DGraphMaterialData structure. PBR related information are read from glTF formats.

Miscellaneous

Supported

• Version 2.0 files only (tinygltf limitation; only “asset” data is correctly parsed from 1.0 files)

• Vertex position, normal, color, texture coordinate sets 0 and 1

• Triangles

• Full texture support and material data: normal, occlusion, emissive

• Physically Based Rendering (PBR) textures and constants: base color, metallness, roughness

• Texture file formats: JPEG, PNG, BMP, GIF (handled by tinygltf)

• Cameras

Unsupported

• Version 1.0 files

• Vertex tangents

• Animations

• Skins

• Extensions

• Shaders

• Sparse accessors (currently not supported by tinygltf)

• Byte-swapping for Big-Endian platforms

Assembly

This concept is not supported by glTF.

B-rep

This concept is not supported by glTF.

Visualization

The triangle information is parsed and provided via HOOPS Exchange.

Views

This concept is not supported by glTF.

PMI

This concept is not supported by glTF.

The detailed description of the material data format is included in the documentation of the A3DGraphMaterialData structure. For more information about accessing textures and attributes, please read the documentation for the A3DGlobalData, A3DGraphMaterialData, A3DGraphTextureApplicationData and A3DMiscAttributeData structures.

Retrictions

Reading glTF is not available on iOS and Android.