private void backgroundWorker1_DoWork(object sender, DoWorkEventArgs e)
{
string[] args = e.Argument as string[];
double avgLength = 0;
double avgSlope = 0;
if (File.Exists(args[0]) && File.Exists(args[1]))
{
FormOutput.AppendLog("开始获取线的交点...");
RasterReader reader = new RasterReader(args[1]);
List <Point3d> pts = CalPoints(args[0], reader);
FormOutput.AppendLog("开始计算平均坡度和坡长...");
CalAvgSlopeLength(pts, reader, ref avgLength, ref avgSlope);
reader.Dispose();
FormOutput.AppendLog("平均坡长：" + avgLength.ToString("f3"));
FormOutput.AppendLog("平均坡度：" + avgSlope.ToString("f3"));
}
double?r = null;
if (File.Exists(args[1]) && File.Exists(args[2]))
{
FormOutput.AppendLog("开始计算坡面流速系数...");
r = RasterCoefficientReader.ReadCoeficient(args[2], args[1]);
if (r.HasValue)
{
FormOutput.AppendLog("结果--坡面流速系数为：" + r.Value.ToString());
}
}
e.Result = new double[] { avgLength, avgSlope, r.GetValueOrDefault(0) };
}
private double CaculateRiver(List <Dictionary <Point2d, Geometry> > dic, string tifPath, ref Dictionary <Point2d, Geometry> mainRiver)
{
RasterReader reader = new RasterReader(tifPath);
//Dictionary<Point2d, Geometry> maxGeoLength = null;
double maxLength = 0; //主沟道长度
List <Point3d> gradientPoints = new List <Point3d>();
// List<Point3d> gradientPoints1 = new List<Point3d>();
int percent = 0;
foreach (var geoLength in dic)
{
double tempLength = 0;
List <Point2d> pointListLength = new List <Point2d>();
gradientPoints = new List <Point3d>();
foreach (var length in geoLength)
{
int pcount = length.Value.GetPointCount();
for (int i = 0; i < pcount; i++)
{
Point2d temp = new Point2d(length.Value.GetX(i), length.Value.GetY(i));
if (!pointListLength.Contains(temp))
{
pointListLength.Add(temp);
gradientPoints.Add(new Point3d(length.Value.GetX(i), length.Value.GetY(i), GetElevationByPointInDEM(temp, reader)));
}
}
}
for (int i = 1; i < gradientPoints.Count; i++)
{
tempLength += GetLength(gradientPoints[i - 1], gradientPoints[i]);
}
if (maxLength < tempLength)
{
maxLength = tempLength;
mainRiver = geoLength;
//gradientPoints1 = gradientPoints;
}
percent++;
FormOutput.AppendProress(percent * 50 / dic.Count);
}
reader.Dispose();
return(maxLength);
}
/// <summary>
/// 用于计算shp文件中的系数平均值
/// </summary>
/// <param name="shppath">shp路径</param>
/// <param name="inputDemPath">tif路径</param>
/// <returns></returns>
public static double?ReadCoeficient(string shppath, string inputDemPath)
{
FormOutput.AppendLog("按规定范围裁剪栅格..");
//创建一个临时目录
string outDemPath = Path.Combine(Path.GetTempPath(), "WDEM.tif");
RasterReader raster = null;
Band band = null;
try
{
ImgCut.CutTiff(shppath, inputDemPath, outDemPath);
if (File.Exists(outDemPath) == false)
{
FormOutput.AppendLog("裁剪失败！");
return(null);
}
FormOutput.AppendLog("开始读取裁剪后的栅格数据..");
raster = new RasterReader(outDemPath);
int row = raster.RowCount;
int col = raster.ColumnCount;
// int count = raster.RasterCount;
int xsize = raster.DataSet.RasterXSize;
int ysize = raster.DataSet.RasterYSize;
band = raster.DataSet.GetRasterBand(1);
//无效值
//FormOutput.AppendLog("获取栅格数据无效值..");
double nodatavalue;
int hasval;
band.GetNoDataValue(out nodatavalue, out hasval);
// FormOutput.AppendLog("栅格数据无效值为" + nodatavalue);
double[] readData = new double[row * col];
band.ReadRaster(0, 0, xsize, ysize, readData, row, col, 0, 0);
//FormOutput.AppendLog("开始整理损失指数数据..");
var res = readData.GroupBy(t => t).Select(t => new { count = t.Count(), Key = t.Key }).ToArray();
double total = 0;
double totalcount = 0;
foreach (var s in res)
{
if (s.Key != nodatavalue)
{
total += s.Key * s.count;
totalcount += s.count;
}
}
double R = total / totalcount;
R = R / 1000; //转换？？
return(R);
}
catch (Exception ex)
{
FormOutput.AppendLog("获取栅格数据异常：" + ex.Message);
return(null);
}
finally
{
//销毁
if (raster != null)
{
band.Dispose();
raster.Dispose();
}
}
}