kml-import-example.cs

using UnityEngine;
using UnityEditor;
using UnityEditor.Experimental.AssetImporters;
using System.IO;
using System.Xml;
using System.Collections.Generic;


[ScriptedImporter(1, "kml")]
public class KMLPathImporter : ScriptedImporter
{
    // public float m_Scale = 1;

    public override void OnImportAsset(AssetImportContext ctx)
    {
        XmlDocument xmlDoc = new XmlDocument();
        xmlDoc.LoadXml(File.ReadAllText(ctx.assetPath));

        XmlNodeList nodes = xmlDoc.GetElementsByTagName("coordinates"); 
        Debug.Log("ok: " +  nodes[0].InnerText);
        char[] splitters = { ',', ' ' };
        var coordStringArray = nodes[0].InnerText.Split(splitters, System.StringSplitOptions.RemoveEmptyEntries);

        var coordStringList = new List<string>();

        for (int i = 0; i < coordStringArray.Length; i++)
        {
            if (coordStringArray[i].Trim() != "")
            {
                coordStringList.Add(coordStringArray[i]);
                Debug.Log(i + ": " + coordStringList[i]);
            }
        }

        int pathCount = coordStringList.Count / 3;

        Location[] locations = new Location[pathCount];

        Debug.Log("coordStringLength: " + coordStringList.Count + "; pathCount = " + pathCount);

        var j = 0;
        for (int i = 0; i < coordStringList.Count; i+=3)
        {
            locations[j] = new Location(
                double.Parse(coordStringList[i + 1], System.Globalization.CultureInfo.InvariantCulture),
                double.Parse(coordStringList[i], System.Globalization.CultureInfo.InvariantCulture),
                double.Parse(coordStringList[i + 2], System.Globalization.CultureInfo.InvariantCulture)
            );
            Debug.Log("Loc: " + j + ": " + locations[j].ToString());

            j++;
        }

        var path = new LocationPath();

        path.locations = locations;

        ctx.AddObjectToAsset("main obj", path);
        ctx.SetMainObject(path);

        Debug.Log(ctx.assetPath);
        var f = ctx.assetPath.Split('.');
        var finalName = f[0] + ".asset";
        AssetDatabase.CreateAsset(path, finalName);

        //var cube = GameObject.CreatePrimitive(PrimitiveType.Cube);
        //var position = JsonUtility.FromJson<Vector3>(File.ReadAllText(ctx.assetPath));

        //cube.transform.position = position;
        //cube.transform.localScale = new Vector3(m_Scale, m_Scale, m_Scale);

        //// 'cube' is a a GameObject and will be automatically converted into a prefab
        //// (Only the 'Main Asset' is elligible to become a Prefab.)
        //ctx.AddObjectToAsset("main obj", cube);
        //ctx.SetMainObject(cube);

        //var material = new Material(Shader.Find("Standard"));
        //material.color = Color.red;

        //// Assets must be assigned a unique identifier string consistent across imports
        //ctx.AddObjectToAsset("my Material", material);

        //// Assets that are not passed into the context as import outputs must be destroyed
        //var tempMesh = new Mesh();
        //DestroyImmediate(tempMesh);
    }
}