unity将图片转换成字体的方法

using UnityEngine;
using System.Collections;
using System;
using System.Xml;

public class CustomFontImportor : MonoBehaviour {

  public Font font;
  public TextAsset textAsset;


  void Awake()
  {
    if (font == null || textAsset == null)
    {
      Debug.LogError("请设置font和textAsset.");
      return;
    }

    XmlDocument xmlDocument = new XmlDocument();
    xmlDocument.LoadXml(textAsset.text);


    int totalWidth = Convert.ToInt32(xmlDocument["font"]["common"].Attributes["scaleW"].InnerText);
    int totalHeight = Convert.ToInt32(xmlDocument["font"]["common"].Attributes["scaleH"].InnerText);

    XmlElement xml = xmlDocument["font"]["chars"];
    ArrayList characterInfoList = new ArrayList();


    for (int i = 0; i < xml.ChildNodes.Count; ++i)
    {
      XmlNode node = xml.ChildNodes[i];
      if (node.Attributes == null)
      {
        continue;
      }
      int index = Convert.ToInt32(node.Attributes["id"].InnerText);
      int x = Convert.ToInt32(node.Attributes["x"].InnerText);
      int y = Convert.ToInt32(node.Attributes["y"].InnerText);
      int width = Convert.ToInt32(node.Attributes["width"].InnerText);
      int height = Convert.ToInt32(node.Attributes["height"].InnerText);
      int xOffset = Convert.ToInt32(node.Attributes["xoffset"].InnerText);
      int yOffset = Convert.ToInt32(node.Attributes["yoffset"].InnerText);
      int xAdvance = Convert.ToInt32(node.Attributes["xadvance"].InnerText);

      CharacterInfo info = new CharacterInfo();
      Rect uv = new Rect();
      uv.x = (float)x / totalWidth;
      uv.y = (float)(totalHeight - y - height) / totalHeight;
      uv.width = (float)width / totalWidth;
      uv.height = (float)height / totalHeight;


      info.index = index;
      info.uvBottomLeft = new Vector2(uv.xMin, uv.yMin);
      info.uvBottomRight = new Vector2(uv.xMax, uv.yMin);
      info.uvTopLeft = new Vector2(uv.xMin, uv.yMax);
      info.uvTopRight = new Vector2(uv.xMax, uv.yMax);
      info.minX = xOffset;
      info.maxX = xOffset + width;
      info.minY = -yOffset - height;
      info.maxY = -yOffset;
      info.advance = xAdvance;
      info.glyphWidth = width;
      info.glyphHeight = height;


      characterInfoList.Add(info);
    }
    font.characterInfo = characterInfoList.ToArray(typeof(CharacterInfo)) as CharacterInfo[];


    Debug.Log("生成成功.");
  }
}