Some properties of the extension (rotation and intensity, for example) seem fairly easy to edit directly in JSON. However, irradianceCoefficients and specularImages do not (unless I’m missing something—please tell me if I am).
Does anyone know of any tools that can export with this glTF extension?
For some background, this extension was created for Adobe Dimension but it’s for their web viewing scenario which uses Babylon. Note that it is an EXT_ and not a KHR_ extension, which just means it’s a multi-vendor extension as opposed to a Khronos version.
I’m not aware of any tools that can create this extension. The Khronos 3D Formats working group is working on the official extension for IBL, but this will take time. We are not likely going to see many tools that have IBL in the glTF until that happens.
Disclaimer: I am part of the Khronos 3D Formats working group.