<@if not DEFAULT_MATERIAL_SLH@> <@def DEFAULT_MATERIAL_SLH@> const float DEFAULT_ROUGHNESS = 0.9; const float DEFAULT_SHININESS = 10.0; const float DEFAULT_METALLIC = 0.0; const vec3 DEFAULT_SPECULAR = vec3(0.1); const vec3 DEFAULT_EMISSIVE = vec3(0.0); const float DEFAULT_OCCLUSION = 1.0; const float DEFAULT_SCATTERING = 0.0; const vec3 DEFAULT_FRESNEL = DEFAULT_EMISSIVE; <@endif@>