/// <summary>
/// 传入坐标获取切片
/// </summary>
/// <param name="x"></param>
/// <param name="y"></param>
/// <param name="z"></param>
public void GetTile(int x, int y, int z)
{
var packSize = this.packSize;
var format = this.storageFormat;
var rGroup = Convert.ToInt32(packSize * Convert.ToInt32(y / packSize));
var cGroup = Convert.ToInt32(packSize * Convert.ToInt32(x / packSize));
var bundleBase = getBundlePath(this.rootPath, z, rGroup, cGroup);
var bundleFileName = bundleBase + ".bundle";
var context = new bundlx()
{
bundleFileName = bundleFileName,
storageFormat = format
};
if (format == formatV1)
{
context.bundlxFileName = bundleBase + ".bundlx";
context.index = packSize * (x - cGroup) + (y - rGroup);
}
else if (format == formatV2)
{
context.index = packSize * (y - rGroup) + (x - cGroup);
}
else
{
throw new Exception("Unsupported format:" + format);
}
readTileFromBundle(context);
}
/// <summary>
/// 读取切片对应字节
/// </summary>
/// <param name="bundleFileName"></param>
/// <param name="offset"></param>
/// <returns></returns>
private byte[] readTile(bundlx context, int offset)
{
byte[] buffer = new byte[4];
byte[] bufferfile = TileCache.Instance[context].BundleData;
//获取bundle具体切片文件字节数
buffer = bufferfile.Skip(offset).Take(4).ToArray();
var length = BitConverter.ToInt32(buffer, 0);
byte[] tileData = new byte[length];
//根据索引和字节数读出文件位置
tileData = bufferfile.Skip(offset + 4).Take(length).ToArray();
return(tileData);
}
private byte[] readTileFromBundleV2(bundlx context)
{
var bundlxFileName = context.bundlxFileName;
var bundleFileName = context.bundleFileName;
var index = context.index;
using (FileStream file = new FileStream(bundlxFileName, FileMode.Open))
{
byte[] buffer = new byte[4];
file.Read(buffer, 64 + 8 * index, 4);
var offset = BitConverter.ToInt32(buffer, 0) - 4;
return(readTile(bundleFileName, offset));
}
}
/// <summary>
/// 读取切片
/// </summary>
/// <param name="context"></param>
/// <returns></returns>
private byte[] readTileFromBundleV1(bundlx context)
{
var bundlxFileName = context.bundlxFileName;
var bundleFileName = context.bundleFileName;
var index = context.index;
byte[] buffer = new byte [5];
byte[] bufferfile = TileCache.Instance[context].BundlxData;
// file.Read(bufferfile,0,(int)file.Length);
//读取bundlx文件存储该切片的位置
buffer = bufferfile.Skip(16 + 5 * index).Take(4).ToArray();
//偏移量
var offset = BitConverter.ToInt32(buffer, 0);
return(readTile(context, offset));
}
/// <summary>
/// 读取切片并保存
/// </summary>
/// <param name="context"></param>
private void readTileFromBundle(bundlx context)
{
byte[] data = null;
if (context.storageFormat == formatV1)
{
data = readTileFromBundleV1(context);
}
else
{
data = readTileFromBundleV2(context);
}
DateTime dt = DateTime.Now;
using (FileStream stream = new FileStream(System.Environment.CurrentDirectory + "/" + string.Format("{0:yyyyMMddHHmmssffff}", dt) + ".jpg", FileMode.OpenOrCreate))
{
stream.Write(data, 0, data.Length);
}
}
/// <summary>
/// 读取切片
/// </summary>
/// <param name="context"></param>
/// <returns></returns>
private byte[] readTileFromBundleV1(bundlx context)
{
var bundlxFileName = context.bundlxFileName;
var bundleFileName = context.bundleFileName;
var index = context.index;
using (FileStream file = new FileStream(bundlxFileName, FileMode.Open))
{
byte[] buffer = new byte [5];
byte[] bufferfile = new byte[file.Length];
file.Read(bufferfile, 0, (int)file.Length);
//读取bundlx文件存储该切片的位置
buffer = bufferfile.Skip(16 + 5 * index).Take(4).ToArray();
//偏移量
var offset = BitConverter.ToInt32(buffer, 0);
return(readTile(bundleFileName, offset));
}
}
