從Fgui中的圖集中取一個圖素，把圖素用到場景等非UI的地方。

此操作會動態建立一個Sprite物件，效率不好，不適合大量使用。

 private static Dictionary<string, Sprite> cacheSpriteByFGUIDic = new Dictionary<string, Sprite>();
/// <summary>
    /// 從FGUI中取一張圖片並返回一個Sprite（不建議頻繁使用）
    /// </summary>
    /// <param name="packageName"></param>
 

    /// <param name="texName"></param>
    public static Sprite GetSpriteByFGUI(string packageName, string texName)
    {
        if (cacheSpriteByFGUIDic.ContainsKey(texName))
            return cacheSpriteByFGUIDic[texName];
        else
        {
            FairyGUI.GImage gImage = FairyGUI.UIPackage.CreateObject(packageName, texName).asImage;
            Rect rect 
 
= new Rect(gImage.texture.uvRect.x * gImage.texture.nativeTexture.width, gImage.texture.uvRect.y * gImage.texture.nativeTexture.height,
               gImage.texture.uvRect.width * gImage.texture.nativeTexture.width, gImage.texture.uvRect.height * gImage.texture.nativeTexture.height);
            Sprite sprite 
 
= Sprite.Create((Texture2D)gImage.texture.nativeTexture, rect, new Vector2(0.5f, 0.5f), 100);
            gImage.Dispose();
            cacheSpriteByFGUIDic.Add(texName, sprite);
            return sprite;
        }
    }