protected static void SerializeProperty(Utf8JsonWriter writer, string name, Matrix4x4?value, Matrix4x4?defval = null) { if (!value.HasValue) { return; } if (defval.HasValue && defval.Value.Equals(value.Value)) { return; } Guard.NotNull(writer, nameof(writer)); writer.WritePropertyName(name); writer.WriteMatrix4x4(value.Value); }