This model demonstrates the usage of the KHR_materials_transmission. The grid of spheres demonstrate different combinations of uniform transmission and textured transmission and how they should render in conjunction with opacity (baseColor.a) and surface roughness/metalicity.
X3D 4.0 Architecture, ISO/IEC 19775-1:2023, 9 Networking component, 12 Shape component, 12.4.2 Appearance
X3D 4.0 Architecture, ISO/IEC 19775-1:2023, clause 9 Networking component, Table 9.3 - Networking component support levels
commented out Tangent nodes, removed flipVertically=true, removed gravityTransform=false since those constructs are not valid X3D4
view3dscene, https://castle-engine.io/view3dscene.php
X3D-Edit 4.0, https://www.web3d.org/x3d/tools/X3D-Edit
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