Beispiel #1
0
        //绘制矢量图层
        private void DrawShpLayer(Graphics g, MapLayer curLayer, int index)
        {
            Ogr.RegisterAll();
            OSGeo.GDAL.Gdal.SetConfigOption("GDAL_DATA", @".\gdal\data");
            DataSource ds = Ogr.Open(curLayer.FilePath, 0);

            //遍历每个图层
            for (int i = 0; i < ds.GetLayerCount(); i++)
            {
                Layer   layer = ds.GetLayerByIndex(i);
                Feature feature;
                //遍历图层中每个要素
                int fid = 0;
                while ((feature = layer.GetNextFeature()) != null)
                {
                    Geometry geom = feature.GetGeometryRef();
                    if (geom != null)
                    {
                        string type = geom.GetGeometryName();
                        if (type == "POLYGON")
                        {
                            DrawPolygon(g, geom, index);
                        }
                        else if (type == "MULTIPOLYGON")
                        {
                            DrawMultiPolygon(g, geom, index);
                        }
                        else if (type == "POINT")
                        {
                            DrawPoint(g, geom, index, fid);
                        }
                        ++fid;
                    }
                }
            }
            ds.FlushCache();
            ds.Dispose();
        }
Beispiel #2
0
        //绘制tiff图层
        private void DrawTiffLayer(Graphics g, MapLayer curLayer, int index)
        {
            //PictureBox pictureBox = new PictureBox();
            float[] MBR = new float[4];
            curLayer.GetExtent(MBR);
            int width, height;
            //根据比例尺确定图片大小和位置
            PointF locationPoint = FromMapPoint(new PointF(MBR[0], MBR[3]));

            if (locationPoint.Y < this.Height && locationPoint.X < this.Width)
            {
                width  = (int)((MBR[2] - MBR[0]) / _DisplayScale);
                height = (int)((MBR[3] - MBR[1]) / _DisplayScale);
                Dataset ds        = Gdal.Open(curLayer.FilePath, Access.GA_ReadOnly);
                int     imgWidth  = ds.RasterXSize;
                int     imgHeight = ds.RasterYSize;
                float[] r         = new float[width * height];
                Band    band      = ds.GetRasterBand(1);
                band.ReadRaster(0, 0, imgWidth, imgHeight, r, width, height, 0, 0);
                //获取NoData值
                double nodata;
                int    handle = 1;
                band.GetNoDataValue(out nodata, out handle);
                double[] MinMax = { 0, 0 };
                band.ComputeRasterMinMax(MinMax, 0);
                int   i, j;
                Color newColor = Color.Transparent;
                for (i = 0; i < width; i++)
                {
                    for (j = 0; j < height; j++)
                    {
                        float value = r[i + j * width];    //像元值
                        if (value > nodata + 1)
                        {
                            if (MapLayers[index].Style.Styles.Count == 0)
                            {
                                int value1 = 0;
                                if (MinMax[0] < -300)//DEM数据拉伸
                                {
                                    if (value >= -128)
                                    {
                                        value1 = (int)((value + 128) / (MinMax[1] + 128) * 205.0 + 50);
                                    }
                                }
                                else
                                {
                                    value1 = (int)((value - MinMax[0]) / (MinMax[1] - MinMax[0]) * 235.0 + 20);
                                }
                                newColor = Color.FromArgb(value1, value1, value1);
                            }
                            else if (MapLayers[index].Style.Styles[0].Rules[0].RasterSymbol.ColorMap.Count == 0)
                            {
                                int value1 = 0;
                                if (MinMax[0] < -300)//DEM数据拉伸
                                {
                                    if (value >= -128)
                                    {
                                        value1 = (int)((value + 128) / (MinMax[1] + 128) * 205.0 + 50);
                                    }
                                }
                                else
                                {
                                    value1 = (int)((value - MinMax[0]) / (MinMax[1] - MinMax[0]) * 235.0 + 20);
                                }
                                newColor = Color.FromArgb(value1, value1, value1);
                                newColor = Color.FromArgb(Convert.ToInt32(255 * curLayer.Style.Styles[0].Rules[0].RasterSymbol.Opacity), newColor);
                            }
                            else // 按照Style绘制
                            {
                                for (int eCount = 0; eCount < curLayer.Style.Styles[0].Rules[0].RasterSymbol.ColorMap.Count - 1; ++eCount)
                                {
                                    if (value >= curLayer.Style.Styles[0].Rules[0].RasterSymbol.ColorMap[eCount].Quantity &&
                                        value <= curLayer.Style.Styles[0].Rules[0].RasterSymbol.ColorMap[eCount + 1].Quantity)
                                    {
                                        newColor = Color.FromArgb(Convert.ToInt32(255 * curLayer.Style.Styles[0].Rules[0].RasterSymbol.ColorMap[eCount].Opacity),
                                                                  ColorTranslator.FromHtml(curLayer.Style.Styles[0].Rules[0].RasterSymbol.ColorMap[eCount].Color));
                                        break;
                                    }
                                }
                            }
                        }
                        g.FillRectangle(new SolidBrush(newColor), new RectangleF(locationPoint.X + i, locationPoint.Y + j, 1, 1));
                    }
                }
                ds.FlushCache();
                ds.Dispose();
            }
        }