public void ToXml(XmlWriter writer)
        {
            writer.WriteStartElement("slope");

            writer.WriteStartElement("float");
            writer.WriteAttributeString("name", "angleDegrees");
            writer.WriteAttributeString("value", AngleDegrees.ToString());
            writer.WriteEndElement();

            writer.WriteStartElement("int");
            writer.WriteAttributeString("name", "textureIndex");
            writer.WriteAttributeString("value", TextureIndex.ToString());
            writer.WriteEndElement();

            writer.WriteEndElement();
        }