(above) Path-traced render via Dassault Systèmes Enterprise PBR with the Artist Workshop environment light.
This model is a hurricane lamp candle holder using the glTF extensions KHR_materials_transmission and KHR_materials_volume to create colored glass.
The color of the glass comes from the attenuationColor and attenuationDistance properties in KHR_materials_volume, along with the thicknessTexture which can be used by non-raytraced renderers to simulate surfaces with varying thickness. Pathtracers can ignore this texture and instead use the geometric thickness from the model for more accurate results.
An earlier version of this model was used in the glTF tutorial Adding Material Extensions to glTF Models. The current version has been improved to demonstrate transmission affected by the colors in baseColorTexture and roughness in metallicRoughnessTexture.
(above) The model viewed in four renderers, from left to right: Microsoft Babylon.js, Google Filament, three.js, and Dassault Systèmes Enterprise PBR. The first three were rendered within Visual Studio Code using the glTF Tools extension.
(C) 2023, Wayfair LLC. CC-BY 4.0 International https://creativecommons.org/licenses/by/4.0/. Model and textures created by Eric Chadwick.