= {
{"emissiveFactor", MaterialAttribute(glm::vec3(0.0))},
{"baseColorFactor", MaterialAttribute(glm::vec3(0.0))},
{"metallicFactor", MaterialAttribute(0.0f)},
{"roughnessFactor", MaterialAttribute(0.0f)},
{"baseColorTexture", MaterialAttribute(OptionalSimpleTexture2D())},
{"metallicRoughnessTexture", MaterialAttribute(OptionalSimpleTexture2D())},
{"normalTexture", MaterialAttribute(OptionalSimpleTexture2D())},
{"occlusionTexture", MaterialAttribute(OptionalSimpleTexture2D())},
{"emissiveTexture", MaterialAttribute(OptionalSimpleTexture2D())}
}