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Textures And Materials
Materials for 3D models are specified in glTF files, and the referenced textures are in *.png format. The materials comply with PBR (Physically Based Rendering). Upon compilation by the glTF compiler (invoked by the Package Tool), *.gltf files get compiled to *.glb and *.png files get compiled to *.dds files. The resulting *.glb file makes use of several glTF extensions, including MSFT_texture_dds as well as Microsoft Flight Simulatorspecific ones.