MeteoInfo-Java解析与绘图教程(六)
这一节主要说的是我们取到自动站的数据,如何通过插值,转化成格点数据,并绘制图层
//从数据库查询cimiss数据
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");
//创建站点格点
StationData stationData = new StationData();
//循环数据将值塞入格点中
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()));
}
//读取地图图层
VectorLayer altMap = MapDataManage.readMapFile_ShapeFile("C:\\Users\\Administrator\\Downloads\\阿勒泰地区\\阿勒泰地区.shp");
//创建网格设置参数
GridDataSetting gridDataSetting = new GridDataSetting();
//设定数据区域
gridDataSetting.dataExtent = altMap.getExtent();
//设定格点数
gridDataSetting.xNum = list.size();
gridDataSetting.yNum = list.size();
//创建插值设置
InterpolationSetting interpolationSetting = new InterpolationSetting();
//设定格点配置
interpolationSetting.setGridDataSetting(gridDataSetting);
//设定插值方法
interpolationSetting.setInterpolationMethod(InterpolationMethods.IDW_Radius);
//设定搜索半径
interpolationSetting.setRadius(10);
//设置最小点数
interpolationSetting.setMinPointNum(1);
//插值到格点
GridData gridData = stationData.interpolateData(interpolationSetting);
LegendScheme als = LgsUtil.readFromLgs("D:\\apache-tomcat-8.0.50\\alt色阶\\color\\ECMWF_HR\\TMP.lgs");
//绘制图层
VectorLayer layer = DrawMeteoData.createShadedLayer(gridData,als,"","",true);
//创建视图
MapView view = new MapView();
PolygonBreak pb = (PolygonBreak) altMap.getLegendScheme().getLegendBreak(0);
pb.setDrawFill(false);
pb.setOutlineColor(Color.GRAY);
layer = layer.clip(altMap);
//叠加图层
view.addLayer(layer);
view.addLayer(altMap);
/**
* 通用方法,可以抽成工具类
*/
MapLayout layout = new MapLayout();
//去除图形边框
layout.getActiveMapFrame().setDrawNeatLine(false);
//区域边界
Extent extent = view.getExtent();
//设置矩形的宽和高
Rectangle bounds = new Rectangle(800, (int) (800 * 1D / extent.getWidth() * extent.getHeight()));
//设置地图边框
layout.setPageBounds(new Rectangle(0, 0, bounds.width, bounds.height));
//设置页面边框
layout.getActiveMapFrame().setLayoutBounds(new Rectangle(0, 0, bounds.width, bounds.height));
layout.getActiveMapFrame().setMapView(view);
layout.exportToPicture(PathUtil.getDeskPath()+"/1.png");
对于该方法主要有几个重点需要关注:
1.GridDataSetting 它是对矩阵做了布局设置
2.InterpolationSetting 它是对插值做了设置,InterpolationMethods就包含了几种插值法,但感觉效果最好的是IDW_Radius,而我们绘制的时候最舒服的方法还是克里金插值,如果可以的话,可以根据原理自己封装一个
图片展示:

简单的绘制基本上都结束了,我也在不停的研究,有新东西我会公布出来,如果大家也有想法可以私聊我来交流一下,让我们对气象开发更加简单舒服