UniVRM/Assets/VRM/Runtime/IO/VRMURPMaterialDescriptorGenerator.cs

using UniGLTF;
using UnityEngine;
using VRMShaders;

namespace VRM
{
    public sealed class VRMUrpMaterialDescriptorGenerator : IMaterialDescriptorGenerator
    {
        readonly glTF_VRM_extensions m_vrm;
        public VRMUrpMaterialDescriptorGenerator(glTF_VRM_extensions vrm)
        {
            m_vrm = vrm;
        }

        public MaterialDescriptor Get(GltfData data, int i)
        {
            // mtoon URP "MToon" shader is not ready. import fallback to unlit
            // unlit "UniUnlit" work in URP
            if (!GltfUnlitMaterialImporter.TryCreateParam(data, i, out MaterialDescriptor matDesc))
            {
                // pbr "Standard" to "Universal Render Pipeline/Lit" 
                if (!GltfPbrUrpMaterialImporter.TryCreateParam(data, i, out matDesc))
                {
                    // fallback
#if VRM_DEVELOP
                    Debug.LogWarning($"material: {i} out of range. fallback");
#endif
                    return new MaterialDescriptor(GltfMaterialDescriptorGenerator.GetMaterialName(i, null), GltfPbrMaterialImporter.ShaderName);
                }
            }
            return matDesc;
        }
    }
}