import java.util.HashMap;
import java.util.List;
import java.util.Map;
+import java.util.Objects;
import javax.measure.Quantity;
import javax.measure.quantity.Area;
import org.geotools.styling.css.CssTranslator;
import org.geotools.styling.css.Stylesheet;
import org.geotools.xml.styling.SLDTransformer;
+import org.locationtech.jts.algorithm.hull.ConcaveHull;
import org.locationtech.jts.geom.Coordinate;
+import org.locationtech.jts.geom.Geometry;
import org.locationtech.jts.geom.Point;
import org.locationtech.jts.geom.Polygon;
+import org.locationtech.jts.geom.util.GeometryFixer;
+import org.locationtech.jts.operation.polygonize.Polygonizer;
import org.opengis.feature.simple.SimpleFeature;
import org.opengis.feature.simple.SimpleFeatureType;
import org.opengis.filter.Filter;
/** In square meters. */
public static Quantity<Area> calcArea(SimpleFeature feature) {
try {
- Polygon p = (Polygon) feature.getDefaultGeometry();
- Point centroid = p.getCentroid();
+ Polygon polygon = (Polygon) feature.getDefaultGeometry();
+ Point centroid = polygon.getCentroid();
+// CoordinateReferenceSystem crs = feature.getDefaultGeometryProperty().getType()
+// .getCoordinateReferenceSystem();
+ // TODO convert the centroid
+// if (!crs.getName().equals(DefaultGeographicCRS.WGS84.getName()))
+// throw new IllegalArgumentException("Only WGS84 CRS is currently supported");
+
+ // create automatic CRS for optimal computation
String code = "AUTO:42001," + centroid.getX() + "," + centroid.getY();
CoordinateReferenceSystem auto = CRS.decode(code);
MathTransform transform = CRS.findMathTransform(DefaultGeographicCRS.WGS84, auto);
- Polygon projed = (Polygon) JTS.transform(p, transform);
+ Polygon projed = (Polygon) JTS.transform(polygon, transform);
return Quantities.getQuantity(projed.getArea(), SI.SQUARE_METRE);
} catch (MismatchedDimensionException | FactoryException | TransformException e) {
- throw new IllegalStateException("Cannot claculate area of feature");
+ throw new IllegalStateException("Cannot calculate area of feature", e);
+ }
+ }
+
+ /** In square meters. The {@link Polygon} must use WGS84 coordinates. */
+ public static Quantity<Area> calcArea(Polygon polygon) {
+ assert polygon.getSRID() == 0 || polygon.getSRID() == 4326;
+ return calcArea(polygon, DefaultGeographicCRS.WGS84, polygon.getCentroid());
+ }
+
+ public static Quantity<Area> calcArea(Polygon polygon, CoordinateReferenceSystem crs, Point wgs84centroid) {
+ try {
+ // create automatic CRS for optimal computation
+ String code = "AUTO:42001," + wgs84centroid.getX() + "," + wgs84centroid.getY();
+ CoordinateReferenceSystem auto = CRS.decode(code);
+
+ MathTransform transform = CRS.findMathTransform(crs, auto);
+
+ Polygon projed = (Polygon) JTS.transform(polygon, transform);
+ return Quantities.getQuantity(projed.getArea(), SI.SQUARE_METRE);
+ } catch (MismatchedDimensionException | FactoryException | TransformException e) {
+ throw new IllegalStateException("Cannot calculate area of feature", e);
}
}
}
public static long getScaleFromResolution(long resolution) {
- // see https://gis.stackexchange.com/questions/242424/how-to-get-map-units-to-find-current-scale-in-openlayers
+ // see
+ // https://gis.stackexchange.com/questions/242424/how-to-get-map-units-to-find-current-scale-in-openlayers
final double INCHES_PER_UNIT = 39.37;// m
// final double INCHES_PER_UNIT = 4374754;// dd
final long DOTS_PER_INCH = 72;
return Math.round(INCHES_PER_UNIT * DOTS_PER_INCH * resolution);
}
+ /*
+ * GEOMETRY
+ */
+ /**
+ * Ensure that a {@link Polygon} is valid and simple by removing artefacts
+ * (typically coming from GPS).
+ *
+ * @return a simple and valid polygon, or null if the ignoredArea ratio is above
+ * the provided threshold.
+ */
+ public static Polygon cleanPolygon(Polygon polygon, double ignoredAreaRatio) {
+ Polygonizer polygonizer = new Polygonizer(true);
+ Geometry fixed = GeometryFixer.fix(polygon, false);
+ polygonizer.add(fixed);
+ @SuppressWarnings("unchecked")
+ List<Polygon> polygons = new ArrayList<>(polygonizer.getPolygons());
+
+ if (polygons.size() == 0) {
+ throw new IllegalStateException("Polygonizer failed to extract any polygon");
+ }
+
+ Polygon best;
+ if (polygons.size() == 1) {
+ best = polygons.get(0);
+ } else {
+ double totalArea = fixed.getArea();
+ best = polygons.get(0);
+ double bestArea = best.getArea();
+ for (int i = 1; i < polygons.size(); i++) {
+ Polygon p = polygons.get(i);
+ double a = p.getArea();
+ if (a > bestArea) {
+ best = p;
+ bestArea = a;
+ } else {
+ // double ratio = a / totalArea;
+ }
+ }
+ double ignoredRatio = (totalArea - bestArea) / totalArea;
+ if (ignoredRatio > ignoredAreaRatio)
+ return null;
+
+ if (!best.isValid() || !best.isSimple()) {
+ throw new IllegalStateException("The polygon is not simple and/or valid after cleaning");
+ }
+ }
+ // while we are here, we make sure that the geometry will be normalised
+ best.normalize();
+ return best;
+ }
+
+ /**
+ * The smallest polygon without holes containing all the points in this
+ * geometry.
+ */
+ public static Polygon concaveHull(Geometry geom, double lengthRatio) {
+ Objects.requireNonNull(geom);
+ if (geom.getNumPoints() < 3)
+ throw new IllegalArgumentException("At least 3 points are reuired to compute the concave hull and geometry "
+ + geom.getClass() + " contains only " + geom.getNumPoints());
+ Geometry hull = ConcaveHull.concaveHullByLengthRatio(geom, lengthRatio, false);
+ if (hull instanceof Polygon polygon)
+ return polygon;
+ else
+ throw new IllegalStateException("Hull is not a polygon but a " + hull.getClass());
+ }
+
/** Singleton. */
private GeoUtils() {
}
projects / gpl / argeo-suite.git / blobdiff