Screenshot from the development version of the glTF Sample Viewer which supports KHR_materials_diffuse_transmission.
This asset is a test of the glTF extension KHR_materials_diffuse_transmission to demonstrate the scattering of light through the fruit of the orange.
Two screenshots, with KHR_materials_diffuse_transmission (left) versus without.
The textures. Top row from left: base color, occlusion, roughness. Bottom row from left: normal, diffuse transmission factor, diffuse transmission color.
The original model on Sketchfab from zandreamer is a photogrammetry asset which only contains a base color texture. All the additional textures were created by processing the base color through a series of filters in various art tools.