USDZExporter: Support MeshPhysicalMaterial (#21901)

examples/js/exporters/USDZExporter.js

@@ -396,6 +396,15 @@ ${array.join( '' )}
 		}
 
 		inputs.push( `${pad}float inputs:opacity = ${material.opacity}` );
+
+		if ( material.isMeshPhysicalMaterial ) {
+
+			inputs.push( `${pad}float inputs:clearcoat = ${material.clearcoat}` );
+			inputs.push( `${pad}float inputs:clearcoatRoughness = ${material.clearcoatRoughness}` );
+			inputs.push( `${pad}float inputs:ior = ${material.ior}` );
+
+		}
+
 		return `
     def Material "Material_${material.id}"
     {

examples/jsm/exporters/USDZExporter.js

@@ -426,6 +426,14 @@ function buildMaterial( material, textures ) {
 
 	inputs.push( `${ pad }float inputs:opacity = ${ material.opacity }` );
 
+	if ( material.isMeshPhysicalMaterial ) {
+
+		inputs.push( `${ pad }float inputs:clearcoat = ${ material.clearcoat }` );
+		inputs.push( `${ pad }float inputs:clearcoatRoughness = ${ material.clearcoatRoughness }` );
+		inputs.push( `${ pad }float inputs:ior = ${ material.ior }` );
+
+	}
+
 	return `
     def Material "Material_${ material.id }"
     {