geom.getEnvelope() 得到外接矩形,不一定是面积最小;可以对多边形的每一条边求外接矩形,然后比较得到最小外接矩形
参考:https://blog.csdn.net/qq_40985985/article/details/127034254
ArrayList<Polygon> polys = new ArrayList<Polygon>(); Polygon bbox = (Polygon) geom.getEnvelope(); polys.add(bbox); geoms.add(geom.getEnvelope()); List<Geometry> geoms = new ArrayList<Geometry>(); //Polygon poly = null; Geometry polyUnion = null; int i=0; while(itr.hasNext()){ SimpleFeature sf = itr.next(); //MultiPolygon geom = (MultiPolygon)sf.getDefaultGeometry(); Geometry geom = (Geometry) sf.getDefaultGeometry(); Polygon bbox = (Polygon) geom.getEnvelope(); //polys.add(bbox); geoms.add(geom.getEnvelope()); if(i==0){ polyUnion = bbox }else { polyUnion = polyUnion.union(bbox); } i++; } itr.close();
//shpReadWrite.CreateNewShapeFile
求并集。。
为什么要这么迂回呢?为什么不直接对原始多边形求并集,然后求外接矩形。。
List<Geometry> geoms = new ArrayList<Geometry>(); Geometry polyUnion = null; int i=0; while(itr.hasNext()){ SimpleFeature sf = itr.next(); Geometry geom = (Geometry) sf.getDefaultGeometry(); if(i==0){ Geometry geom2 = geom.intersection(geom);//避免自交 polyUnion = geom2; }else { Geometry geom2 = geom.intersection(geom);//避免自交 polyUnion = polyUnion.union(geom2); } i++; } itr.close();
s.geom.TopologyException: found non-noded intersection between LINESTRING........geotools空间分析存在自相交情况时的错误解决:先和自己自交,再求并集。。
>>更简单的办法:
SimpleFeatureCollection fc = contentFeatureSource.getFeatures();
double minX = fc.getBounds().getMinX();
...