MeteoInfo-Java解析與繪圖教程(六)

這一節主要說的是我們取到自動站的資料,如何通過插值,轉化成格點資料,並繪製圖層

        //從資料庫查詢cimiss資料
        List<Map<String,Object>> list = DBUtil.getMapList("SELECT * FROM mete_stationpar_data_2021 WHERE DataTime = '2021-01-01 12:00:00' AND TEM IS NOT NULL");
        //建立站點格點
        StationData stationData = new StationData();
        //迴圈資料將值塞入格點中
        for (Map<String, Object> item : list) {
            System.out.println(item);
            stationData.addData(String.valueOf(item.get("Station_Name")),
                    Double.parseDouble(item.get("Lon").toString()),
                    Double.parseDouble(item.get("Lat").toString()),
                    Double.parseDouble(item.get("TEM").toString()));
        }
        //讀取地圖圖層
        VectorLayer altMap = MapDataManage.readMapFile_ShapeFile("C:\\Users\\Administrator\\Downloads\\阿勒泰地區\\阿勒泰地區.shp");
        //建立網格設定引數
        GridDataSetting gridDataSetting = new GridDataSetting();
        //設定資料區域
        gridDataSetting.dataExtent = altMap.getExtent();
        //設定格點數
        gridDataSetting.xNum = list.size();
        gridDataSetting.yNum = list.size();
        //建立插值設定
        InterpolationSetting interpolationSetting = new InterpolationSetting();
        //設定格點配置
        interpolationSetting.setGridDataSetting(gridDataSetting);
        //設定插值方法
        interpolationSetting.setInterpolationMethod(InterpolationMethods.IDW_Radius);
        //設定搜尋半徑
        interpolationSetting.setRadius(10);
        //設定最小點數
        interpolationSetting.setMinPointNum(1);
        //插值到格點
        GridData gridData = stationData.interpolateData(interpolationSetting);
        LegendScheme als = LgsUtil.readFromLgs("D:\\apache-tomcat-8.0.50\\alt色階\\color\\ECMWF_HR\\TMP.lgs");
        //繪製圖層
        VectorLayer layer = DrawMeteoData.createShadedLayer(gridData,als,"","",true);
        //建立檢視
        MapView view = new MapView();
        PolygonBreak pb = (PolygonBreak) altMap.getLegendScheme().getLegendBreak(0);
        pb.setDrawFill(false);
        pb.setOutlineColor(Color.GRAY);
        layer = layer.clip(altMap);
        //疊加圖層
        view.addLayer(layer);
        view.addLayer(altMap);


        /**
         * 通用方法,可以抽成工具類
         */
        MapLayout layout  = new MapLayout();
        //去除圖形邊框
        layout.getActiveMapFrame().setDrawNeatLine(false);
        //區域邊界
        Extent extent = view.getExtent();
        //設定矩形的寬和高
        Rectangle bounds = new Rectangle(800, (int) (800 * 1D / extent.getWidth() * extent.getHeight()));
        //設定地圖邊框
        layout.setPageBounds(new Rectangle(0, 0, bounds.width, bounds.height));
        //設定頁面邊框
        layout.getActiveMapFrame().setLayoutBounds(new Rectangle(0, 0, bounds.width, bounds.height));
        layout.getActiveMapFrame().setMapView(view);
        layout.exportToPicture(PathUtil.getDeskPath()+"/1.png");

對於該方法主要有幾個重點需要關注:

1.GridDataSetting 它是對矩陣做了佈局設定

2.InterpolationSetting 它是對插值做了設定,InterpolationMethods就包含了幾種插值法,但感覺效果最好的是IDW_Radius,而我們繪製的時候最舒服的方法還是克里金插值,如果可以的話,可以根據原理自己封裝一個

圖片展示:

簡單的繪製基本上都結束了,我也在不停的研究,有新東西我會公佈出來,如果大家也有想法可以私聊我來交流一下,讓我們對氣象開發更加簡單舒服