org.argeo.app.core/src/org/argeo/app/geo/GeoUtils.java

   1 package org.argeo.app.geo;
   2
   3 import java.io.IOException;
   4 import java.io.Serializable;
   5 import java.io.Writer;
   6 import java.nio.file.Path;
   7 import java.util.ArrayList;
   8 import java.util.HashMap;
   9 import java.util.List;
  10 import java.util.Map;
  11
  12 import javax.measure.Quantity;
  13 import javax.measure.quantity.Area;
  14
  15 import org.geotools.data.DefaultTransaction;
  16 import org.geotools.data.Transaction;
  17 import org.geotools.data.collection.ListFeatureCollection;
  18 import org.geotools.data.shapefile.ShapefileDataStore;
  19 import org.geotools.data.shapefile.ShapefileDataStoreFactory;
  20 import org.geotools.data.simple.SimpleFeatureCollection;
  21 import org.geotools.data.simple.SimpleFeatureIterator;
  22 import org.geotools.data.simple.SimpleFeatureSource;
  23 import org.geotools.data.simple.SimpleFeatureStore;
  24 import org.geotools.geometry.jts.JTS;
  25 import org.geotools.referencing.CRS;
  26 import org.geotools.referencing.crs.DefaultGeographicCRS;
  27 import org.locationtech.jts.geom.Coordinate;
  28 import org.locationtech.jts.geom.Point;
  29 import org.locationtech.jts.geom.Polygon;
  30 import org.opengis.feature.simple.SimpleFeature;
  31 import org.opengis.feature.simple.SimpleFeatureType;
  32 import org.opengis.geometry.MismatchedDimensionException;
  33 import org.opengis.referencing.FactoryException;
  34 import org.opengis.referencing.crs.CoordinateReferenceSystem;
  35 import org.opengis.referencing.operation.MathTransform;
  36 import org.opengis.referencing.operation.TransformException;
  37
  38 import si.uom.SI;
  39 import tech.units.indriya.quantity.Quantities;
  40
  41 /** Utilities around geographical format, mostly wrapping GeoTools patterns. */
  42 public class GeoUtils {
  43
  44         /** In square meters. */
  45         public static Quantity<Area> calcArea(SimpleFeature feature) {
  46                 try {
  47                         Polygon p = (Polygon) feature.getDefaultGeometry();
  48                         Point centroid = p.getCentroid();
  49                         String code = "AUTO:42001," + centroid.getX() + "," + centroid.getY();
  50                         CoordinateReferenceSystem auto = CRS.decode(code);
  51
  52                         MathTransform transform = CRS.findMathTransform(DefaultGeographicCRS.WGS84, auto);
  53
  54                         Polygon projed = (Polygon) JTS.transform(p, transform);
  55                         return Quantities.getQuantity(projed.getArea(), SI.SQUARE_METRE);
  56                 } catch (MismatchedDimensionException | FactoryException | TransformException e) {
  57                         throw new IllegalStateException("Cannot claculate area of feature");
  58                 }
  59         }
  60
  61         public static void exportToSvg(SimpleFeatureCollection features, Writer out, int width, int height) {
  62                 try {
  63                         double minY = Double.POSITIVE_INFINITY;
  64                         double maxY = Double.NEGATIVE_INFINITY;
  65                         double minX = Double.POSITIVE_INFINITY;
  66                         double maxX = Double.NEGATIVE_INFINITY;
  67                         List<String> shapes = new ArrayList<>();
  68                         for (SimpleFeatureIterator it = features.features(); it.hasNext();) {
  69                                 SimpleFeature feature = it.next();
  70                                 StringBuffer sb = new StringBuffer();
  71                                 sb.append("<polyline style=\"stroke-width:1;stroke:#000000;fill:none;\" points=\"");
  72
  73                                 Polygon p = (Polygon) feature.getDefaultGeometry();
  74                                 Point centroid = p.getCentroid();
  75                                 String code = "AUTO:42001," + centroid.getX() + "," + centroid.getY();
  76                                 CoordinateReferenceSystem auto = CRS.decode(code);
  77
  78                                 MathTransform transform = CRS.findMathTransform(DefaultGeographicCRS.WGS84, auto);
  79
  80                                 Polygon projed = (Polygon) JTS.transform(p, transform);
  81
  82                                 for (Coordinate coord : projed.getCoordinates()) {
  83                                         double x = coord.x;
  84                                         if (x < minX)
  85                                                 minX = x;
  86                                         if (x > maxX)
  87                                                 maxX = x;
  88                                         double y = -coord.y;
  89                                         if (y < minY)
  90                                                 minY = y;
  91                                         if (y > maxY)
  92                                                 maxY = y;
  93                                         sb.append(x + "," + y + " ");
  94                                 }
  95                                 sb.append("\">");
  96                                 sb.append("</polyline>\n");
  97                                 shapes.add(sb.toString());
  98
  99                         }
 100                         double viewportHeight = maxY - minY;
 101                         double viewportWidth = maxX - minX;
 102                         out.write("<svg xmlns=\"http://www.w3.org/2000/svg\"\n");
 103                         out.write(" width=\"" + width + "\"\n");
 104                         out.write(" height=\"" + height + "\"\n");
 105                         out.write(" viewBox=\"" + minX + " " + minY + " " + viewportWidth + " " + viewportHeight + "\"\n");
 106                         out.write(" preserveAspectRatio=\"xMidYMid meet\"\n");
 107                         out.write(">\n");
 108                         for (String shape : shapes) {
 109                                 out.write(shape);
 110                                 out.write("\n");
 111                         }
 112                         out.write("</svg>");
 113                 } catch (IOException | FactoryException | MismatchedDimensionException | TransformException e) {
 114                         throw new RuntimeException("Cannot export to SVG", e);
 115                 }
 116         }
 117
 118         /** Write a list of simple features to a shapefile. */
 119         public static void saveFeaturesAsShapefile(SimpleFeatureType featureType, List<SimpleFeature> features,
 120                         Path shpFile) {
 121                 try {
 122                         ShapefileDataStoreFactory dataStoreFactory = new ShapefileDataStoreFactory();
 123
 124                         Map<String, Serializable> params = new HashMap<>();
 125                         params.put("url", shpFile.toUri().toURL());
 126
 127                         params.put("create spatial index", Boolean.TRUE);
 128
 129                         ShapefileDataStore newDataStore = (ShapefileDataStore) dataStoreFactory.createNewDataStore(params);
 130                         newDataStore.createSchema(featureType);
 131
 132                         String typeName = newDataStore.getTypeNames()[0];
 133                         SimpleFeatureSource featureSource = newDataStore.getFeatureSource(typeName);
 134                         if (featureSource instanceof SimpleFeatureStore) {
 135                                 SimpleFeatureStore featureStore = (SimpleFeatureStore) featureSource;
 136                                 SimpleFeatureCollection collection = new ListFeatureCollection(featureType, features);
 137
 138                                 try (Transaction transaction = new DefaultTransaction("create")) {
 139                                         try {
 140                                                 featureStore.setTransaction(transaction);
 141                                                 featureStore.addFeatures(collection);
 142                                                 transaction.commit();
 143                                         } catch (Exception problem) {
 144                                                 transaction.rollback();
 145                                                 throw new RuntimeException("Cannot write shapefile " + shpFile, problem);
 146                                         }
 147                                 }
 148                         } else {
 149                                 throw new IllegalArgumentException(typeName + " does not support read/write access");
 150                         }
 151                 } catch (IOException e) {
 152                         throw new RuntimeException("Cannot write shapefile " + shpFile, e);
 153                 }
 154         }
 155
 156         /** Singleton. */
 157         private GeoUtils() {
 158         }
 159 }