org.jgrasstools.gears.utils.geometry.GeometryUtilities Maven / Gradle / Ivy
/*
* JGrass - Free Open Source Java GIS http://www.jgrass.org
* (C) HydroloGIS - www.hydrologis.com
*
* This library is free software; you can redistribute it and/or modify it under
* the terms of the GNU Library General Public License as published by the Free
* Software Foundation; either version 2 of the License, or (at your option) any
* later version.
*
* This library is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
* FOR A PARTICULAR PURPOSE. See the GNU Library General Public License for more
* details.
*
* You should have received a copy of the GNU Library General Public License
* along with this library; if not, write to the Free Foundation, Inc., 59
* Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
package org.jgrasstools.gears.utils.geometry;
import static java.lang.Math.abs;
import static java.lang.Math.acos;
import static java.lang.Math.atan;
import static java.lang.Math.max;
import static java.lang.Math.min;
import static java.lang.Math.sqrt;
import static java.lang.Math.toDegrees;
import static java.lang.Math.toRadians;
import java.awt.geom.AffineTransform;
import java.awt.geom.Rectangle2D;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collection;
import java.util.List;
import org.geotools.geometry.jts.JTS;
import org.geotools.referencing.GeodeticCalculator;
import org.geotools.referencing.operation.transform.AffineTransform2D;
import org.jgrasstools.gears.libs.monitor.DummyProgressMonitor;
import org.jgrasstools.gears.utils.math.NumericsUtilities;
import org.jgrasstools.gears.utils.sorting.QuickSortAlgorithm;
import org.opengis.feature.type.GeometryDescriptor;
import com.vividsolutions.jts.algorithm.PointLocator;
import com.vividsolutions.jts.algorithm.RobustLineIntersector;
import com.vividsolutions.jts.geom.Coordinate;
import com.vividsolutions.jts.geom.Envelope;
import com.vividsolutions.jts.geom.Geometry;
import com.vividsolutions.jts.geom.GeometryCollection;
import com.vividsolutions.jts.geom.GeometryFactory;
import com.vividsolutions.jts.geom.LineSegment;
import com.vividsolutions.jts.geom.LineString;
import com.vividsolutions.jts.geom.LinearRing;
import com.vividsolutions.jts.geom.Location;
import com.vividsolutions.jts.geom.MultiLineString;
import com.vividsolutions.jts.geom.MultiPoint;
import com.vividsolutions.jts.geom.MultiPolygon;
import com.vividsolutions.jts.geom.Point;
import com.vividsolutions.jts.geom.Polygon;
import com.vividsolutions.jts.geom.PrecisionModel;
import com.vividsolutions.jts.geom.util.AffineTransformation;
import com.vividsolutions.jts.index.chain.MonotoneChain;
import com.vividsolutions.jts.index.quadtree.Quadtree;
import com.vividsolutions.jts.index.strtree.STRtree;
import com.vividsolutions.jts.linearref.LengthIndexedLine;
import com.vividsolutions.jts.noding.IntersectionAdder;
import com.vividsolutions.jts.noding.MCIndexNoder;
import com.vividsolutions.jts.noding.NodedSegmentString;
import com.vividsolutions.jts.operation.linemerge.LineMerger;
import com.vividsolutions.jts.operation.polygonize.Polygonizer;
import com.vividsolutions.jts.operation.union.CascadedPolygonUnion;
/**
* Utilities related to {@link Geometry}.
*
* @author Andrea Antonello (www.hydrologis.com)
*/
public class GeometryUtilities {
public static Geometry[] TYPE_GEOMETRY = new Geometry[0];
public static Polygon[] TYPE_POLYGON = new Polygon[0];
public static MultiPolygon[] TYPE_MULTIPOLYGON = new MultiPolygon[0];
public static LineString[] TYPE_LINESTRING = new LineString[0];
public static MultiLineString[] TYPE_MULTILINESTRING = new MultiLineString[0];
public static Point[] TYPE_POINT = new Point[0];
public static MultiPoint[] TYPE_MULTIPOINT = new MultiPoint[0];
private static GeometryFactory geomFactory;
private static PrecisionModel precModel;
public static PrecisionModel basicPrecisionModel() {
return (pm());
}
public static GeometryFactory gf() {
if (geomFactory == null) {
geomFactory = new GeometryFactory(pm());
}
return (geomFactory);
}
public static PrecisionModel pm() {
if (precModel == null) {
precModel = new PrecisionModel(PrecisionModel.FLOATING);
}
return (precModel);
}
/**
* Create a simple polygon (no holes).
*
* @param coords the coords of the polygon.
* @return the {@link Polygon}.
*/
public static Polygon createSimplePolygon( Coordinate[] coords ) {
LinearRing linearRing = gf().createLinearRing(coords);
return gf().createPolygon(linearRing, null);
}
/**
* Creates a polygon that may help out as placeholder.
*
* @return a dummy {@link Polygon}.
*/
public static Polygon createDummyPolygon() {
Coordinate[] c = new Coordinate[]{new Coordinate(0.0, 0.0), new Coordinate(1.0, 1.0), new Coordinate(1.0, 0.0),
new Coordinate(0.0, 0.0)};
LinearRing linearRing = gf().createLinearRing(c);
return gf().createPolygon(linearRing, null);
}
/**
* Creates a line that may help out as placeholder.
*
* @return a dummy {@link LineString}.
*/
public static LineString createDummyLine() {
Coordinate[] c = new Coordinate[]{new Coordinate(0.0, 0.0), new Coordinate(1.0, 1.0), new Coordinate(1.0, 0.0)};
LineString lineString = gf().createLineString(c);
return lineString;
}
/**
* Creates a point that may help out as placeholder.
*
* @return a dummy {@link Point}.
*/
public static Point createDummyPoint() {
Point point = gf().createPoint(new Coordinate(0.0, 0.0));
return point;
}
public static Polygon createPolygonFromEnvelope( Envelope env ) {
double minX = env.getMinX();
double minY = env.getMinY();
double maxY = env.getMaxY();
double maxX = env.getMaxX();
Coordinate[] c = new Coordinate[]{new Coordinate(minX, minY), new Coordinate(minX, maxY), new Coordinate(maxX, maxY),
new Coordinate(maxX, minY), new Coordinate(minX, minY)};
return gf().createPolygon(c);
}
public static Geometry createPolygonsFromRanges( double[] xRanges, double[] yRanges ) {
List geomsList = new ArrayList<>();
int cols = xRanges.length - 1;
int rows = yRanges.length - 1;
for( int x = 0; x < cols - 1; x++ ) {
double x1 = xRanges[x];
double x2 = xRanges[x + 1];
for( int y = 0; y < rows - 1; y++ ) {
double y1 = xRanges[y];
double y2 = xRanges[y + 1];
Envelope env = new Envelope(x1, x2, y1, y2);
Polygon poly = GeometryUtilities.createPolygonFromEnvelope(env);
geomsList.add(poly);
}
}
Geometry union = CascadedPolygonUnion.union(geomsList);
return union;
}
public static List extractSubGeometries( Geometry geometry ) {
List geometriesList = new ArrayList();
int numGeometries = geometry.getNumGeometries();
for( int i = 0; i < numGeometries; i++ ) {
Geometry geometryN = geometry.getGeometryN(i);
geometriesList.add(geometryN);
}
return geometriesList;
}
/**
* Calculates the angle between two {@link LineSegment}s.
*
* @param l1 the first segment.
* @param l2 the second segment.
* @return the angle between the two segments, starting from the first segment
* moving clockwise.
*/
public static double angleBetween( LineSegment l1, LineSegment l2 ) {
double azimuth1 = azimuth(l1.p0, l1.p1);
double azimuth2 = azimuth(l2.p0, l2.p1);
if (azimuth1 < azimuth2) {
return azimuth2 - azimuth1;
} else {
return 360 - azimuth1 + azimuth2;
}
}
/**
* Calculates the azimuth in degrees given two {@link Coordinate} composing a line.
*
* Note that the coords order is important and will differ of 180.
*
* @param c1 first coordinate (used as origin).
* @param c2 second coordinate.
* @return the azimuth angle.
*/
public static double azimuth( Coordinate c1, Coordinate c2 ) {
// vertical
if (c1.x == c2.x) {
if (c1.y == c2.y) {
// same point
return Double.NaN;
} else if (c1.y < c2.y) {
return 0.0;
} else if (c1.y > c2.y) {
return 180.0;
}
}
// horiz
if (c1.y == c2.y) {
if (c1.x < c2.x) {
return 90.0;
} else if (c1.x > c2.x) {
return 270.0;
}
}
// -> /
if (c1.x < c2.x && c1.y < c2.y) {
double tanA = (c2.x - c1.x) / (c2.y - c1.y);
double atan = atan(tanA);
return toDegrees(atan);
}
// -> \
if (c1.x < c2.x && c1.y > c2.y) {
double tanA = (c1.y - c2.y) / (c2.x - c1.x);
double atan = atan(tanA);
return toDegrees(atan) + 90.0;
}
// <- /
if (c1.x > c2.x && c1.y > c2.y) {
double tanA = (c1.x - c2.x) / (c1.y - c2.y);
double atan = atan(tanA);
return toDegrees(atan) + 180;
}
// <- \
if (c1.x > c2.x && c1.y < c2.y) {
double tanA = (c2.y - c1.y) / (c1.x - c2.x);
double atan = atan(tanA);
return toDegrees(atan) + 270;
}
return Double.NaN;
}
/**
* Returns the {@link GeometryType} for a given {@link Geometry}.
*
* @param geometry the geometry to check.
* @return the type.
*/
public static GeometryType getGeometryType( Geometry geometry ) {
if (geometry instanceof LineString) {
return GeometryType.LINE;
} else if (geometry instanceof MultiLineString) {
return GeometryType.MULTILINE;
} else if (geometry instanceof Point) {
return GeometryType.POINT;
} else if (geometry instanceof MultiPoint) {
return GeometryType.MULTIPOINT;
} else if (geometry instanceof Polygon) {
return GeometryType.POLYGON;
} else if (geometry instanceof MultiPolygon) {
return GeometryType.MULTIPOLYGON;
} else if (geometry instanceof GeometryCollection) {
return GeometryType.GEOMETRYCOLLECTION;
} else {
return null;
}
}
/**
* Returns the {@link GeometryType} for a given {@link org.opengis.feature.type.GeometryType}.
*
* @param geometryType the geometry type to check.
* @return the type.
*/
public static GeometryType getGeometryType( org.opengis.feature.type.GeometryType geometryType ) {
Class< ? > binding = geometryType.getBinding();
if (binding == LineString.class) {
return GeometryType.LINE;
} else if (binding == MultiLineString.class) {
return GeometryType.MULTILINE;
} else if (binding == Point.class) {
return GeometryType.POINT;
} else if (binding == MultiPoint.class) {
return GeometryType.MULTIPOINT;
} else if (binding == Polygon.class) {
return GeometryType.POLYGON;
} else if (binding == MultiPolygon.class) {
return GeometryType.MULTIPOLYGON;
} else {
return null;
}
}
/**
* Checks if the given geometry is a {@link LineString} (or {@link MultiLineString}) geometry.
*
* @param geometry the geometry to check.
* @return true if there are lines in there.
*/
public static boolean isLine( Geometry geometry ) {
if (geometry instanceof LineString || geometry instanceof MultiLineString) {
return true;
}
return false;
}
/**
* Checks if the given {@link GeometryDescriptor} is for {@link LineString} (or {@link MultiLineString}) geometry.
*
* @param geometryDescriptor the descriptor.
* @return true if there are points in there.
*/
public static boolean isLine( GeometryDescriptor geometryDescriptor ) {
org.opengis.feature.type.GeometryType type = geometryDescriptor.getType();
Class< ? > binding = type.getBinding();
if (binding == MultiLineString.class || binding == LineString.class) {
return true;
}
return false;
}
/**
* Checks if the given geometry is a {@link Polygon} (or {@link MultiPolygon}) geometry.
*
* @param geometry the geometry to check.
* @return true if there are polygons in there.
*/
public static boolean isPolygon( Geometry geometry ) {
if (geometry instanceof Polygon || geometry instanceof MultiPolygon) {
return true;
}
return false;
}
/**
* Checks if the given {@link GeometryDescriptor} is for {@link Polygon} (or {@link MultiPolygon}) geometry.
*
* @param geometryDescriptor the descriptor.
* @return true if there are polygons in there.
*/
public static boolean isPolygon( GeometryDescriptor geometryDescriptor ) {
org.opengis.feature.type.GeometryType type = geometryDescriptor.getType();
Class< ? > binding = type.getBinding();
if (binding == MultiPolygon.class || binding == Polygon.class) {
return true;
}
return false;
}
/**
* Checks if the given geometry is a {@link Point} (or {@link MultiPoint}) geometry.
*
* @param geometry the geometry to check.
* @return true if there are points in there.
*/
public static boolean isPoint( Geometry geometry ) {
if (geometry instanceof Point || geometry instanceof MultiPoint) {
return true;
}
return false;
}
/**
* Checks if the given {@link GeometryDescriptor} is for {@link Point} (or {@link MultiPoint}) geometry.
*
* @param geometryDescriptor the descriptor.
* @return true if there are points in there.
*/
public static boolean isPoint( GeometryDescriptor geometryDescriptor ) {
org.opengis.feature.type.GeometryType type = geometryDescriptor.getType();
Class< ? > binding = type.getBinding();
if (binding == MultiPoint.class || binding == Point.class) {
return true;
}
return false;
}
/**
* Calculates the area of a polygon from its vertices.
*
* @param x the array of x coordinates.
* @param y the array of y coordinates.
* @param N the number of sides of the polygon.
* @return the area of the polygon.
*/
public static double getPolygonArea( int[] x, int[] y, int N ) {
int i, j;
double area = 0;
for( i = 0; i < N; i++ ) {
j = (i + 1) % N;
area += x[i] * y[j];
area -= y[i] * x[j];
}
area /= 2;
return (area < 0 ? -area : area);
}
/**
* Calculates the 3d distance between two coordinates that have an elevation information.
*
* Note that the {@link Coordinate#distance(Coordinate)} method does only 2d.
*
* @param c1 coordinate 1.
* @param c2 coordinate 2.
* @param geodeticCalculator If supplied it will be used for planar distance calculation.
* @return the distance considering also elevation.
*/
public static double distance3d( Coordinate c1, Coordinate c2, GeodeticCalculator geodeticCalculator ) {
if (Double.isNaN(c1.z) || Double.isNaN(c2.z)) {
throw new IllegalArgumentException("Missing elevation information in the supplied coordinates.");
}
double deltaElev = Math.abs(c1.z - c2.z);
double projectedDistance;
if (geodeticCalculator != null) {
geodeticCalculator.setStartingGeographicPoint(c1.x, c1.y);
geodeticCalculator.setDestinationGeographicPoint(c2.x, c2.y);
projectedDistance = geodeticCalculator.getOrthodromicDistance();
} else {
projectedDistance = c1.distance(c2);
}
double distance = NumericsUtilities.pythagoras(projectedDistance, deltaElev);
return distance;
}
public static void sortHorizontal( Coordinate[] coordinates ) {
QuickSortAlgorithm sorter = new QuickSortAlgorithm(new DummyProgressMonitor());
double[] x = new double[coordinates.length];
double[] y = new double[coordinates.length];
for( int i = 0; i < x.length; i++ ) {
x[i] = coordinates[i].x;
y[i] = coordinates[i].y;
}
sorter.sort(x, y);
for( int i = 0; i < x.length; i++ ) {
coordinates[i].x = x[i];
coordinates[i].y = y[i];
}
}
/**
* Joins two lines to a polygon.
*
* @param checkValid checks if the resulting polygon is valid.
* @param lines the lines to use.
* @return the joined polygon or null if something ugly happened.
*/
public static Polygon lines2Polygon( boolean checkValid, LineString... lines ) {
List coordinatesList = new ArrayList();
List linesList = new ArrayList();
for( LineString tmpLine : lines ) {
linesList.add(tmpLine);
}
LineString currentLine = linesList.get(0);
linesList.remove(0);
while( linesList.size() > 0 ) {
Coordinate[] coordinates = currentLine.getCoordinates();
List tmpList = Arrays.asList(coordinates);
coordinatesList.addAll(tmpList);
Point thePoint = currentLine.getEndPoint();
double minDistance = Double.MAX_VALUE;
LineString minDistanceLine = null;
boolean needFlip = false;
for( LineString tmpLine : linesList ) {
Point tmpStartPoint = tmpLine.getStartPoint();
double distance = thePoint.distance(tmpStartPoint);
if (distance < minDistance) {
minDistance = distance;
minDistanceLine = tmpLine;
needFlip = false;
}
Point tmpEndPoint = tmpLine.getEndPoint();
distance = thePoint.distance(tmpEndPoint);
if (distance < minDistance) {
minDistance = distance;
minDistanceLine = tmpLine;
needFlip = true;
}
}
linesList.remove(minDistanceLine);
if (needFlip) {
minDistanceLine = (LineString) minDistanceLine.reverse();
}
currentLine = minDistanceLine;
}
// add last
Coordinate[] coordinates = currentLine.getCoordinates();
List tmpList = Arrays.asList(coordinates);
coordinatesList.addAll(tmpList);
coordinatesList.add(coordinatesList.get(0));
LinearRing linearRing = gf().createLinearRing(coordinatesList.toArray(new Coordinate[0]));
Polygon polygon = gf().createPolygon(linearRing, null);
if (checkValid) {
if (!polygon.isValid()) {
return null;
}
}
return polygon;
}
/**
* Returns the coordinates at a given interval along the line.
*
*
* Note that first and last coordinate are also added, making it
* likely that the interval between the last two coordinates is less
* than the supplied interval.
*
*
*
* @param line the line to use.
* @param interval the interval to use as distance between coordinates. Has to be > 0.
* @param keepExisting if true, keeps the existing coordinates in the generated list.
* Aslo in this case the interval around the existing points will not reflect the asked interval.
* @param startFrom if > 0, it defines the initial distance to jump.
* @param endAt if > 0, it defines where to end, even if the line is longer.
* @return the list of extracted coordinates.
*/
public static List getCoordinatesAtInterval( LineString line, double interval, boolean keepExisting,
double startFrom, double endAt ) {
if (interval <= 0) {
throw new IllegalArgumentException("Interval needs to be > 0.");
}
double length = line.getLength();
if (startFrom < 0) {
startFrom = 0.0;
}
if (endAt < 0) {
endAt = length;
}
List coordinatesList = new ArrayList();
LengthIndexedLine indexedLine = new LengthIndexedLine(line);
Coordinate[] existingCoordinates = null;
double[] indexOfExisting = null;
if (keepExisting) {
existingCoordinates = line.getCoordinates();
indexOfExisting = new double[existingCoordinates.length];
int i = 0;
for( Coordinate coordinate : existingCoordinates ) {
double indexOf = indexedLine.indexOf(coordinate);
indexOfExisting[i] = indexOf;
i++;
}
}
double runningLength = startFrom;
int currentIndexOfexisting = 1; // jump first
while( runningLength < endAt ) {
if (keepExisting && currentIndexOfexisting < indexOfExisting.length - 1
&& runningLength > indexOfExisting[currentIndexOfexisting]) {
// add the existing
coordinatesList.add(existingCoordinates[currentIndexOfexisting]);
currentIndexOfexisting++;
continue;
}
Coordinate extractedPoint = indexedLine.extractPoint(runningLength);
coordinatesList.add(extractedPoint);
runningLength = runningLength + interval;
}
Coordinate extractedPoint = indexedLine.extractPoint(endAt);
coordinatesList.add(extractedPoint);
return coordinatesList;
}
/**
* Extracts traversal sections of a given with from the supplied {@link Coordinate}s.
*
* @param coordinates the list of coordinates.
* @param width the total with of the sections.
* @return the list of {@link LineString sections}.
*/
public static List getSectionsFromCoordinates( List coordinates, double width ) {
if (coordinates.size() < 3) {
throw new IllegalArgumentException("This method works only on lines with at least 3 coordinates.");
}
double halfWidth = width / 2.0;
List linesList = new ArrayList();
// first section
Coordinate centerCoordinate = coordinates.get(0);
LineSegment l1 = new LineSegment(centerCoordinate, coordinates.get(1));
Coordinate leftCoordinate = l1.pointAlongOffset(0.0, halfWidth);
Coordinate rightCoordinate = l1.pointAlongOffset(0.0, -halfWidth);
LineString lineString = geomFactory.createLineString(new Coordinate[]{leftCoordinate, centerCoordinate, rightCoordinate});
linesList.add(lineString);
for( int i = 1; i < coordinates.size() - 1; i++ ) {
Coordinate previous = coordinates.get(i - 1);
Coordinate current = coordinates.get(i);
Coordinate after = coordinates.get(i + 1);
double firstAngle = azimuth(current, previous);
double secondAngle = azimuth(current, after);
double a1 = min(firstAngle, secondAngle);
double a2 = max(firstAngle, secondAngle);
double centerAngle = a1 + (a2 - a1) / 2.0;
AffineTransformation rotationInstance = AffineTransformation.rotationInstance(-toRadians(centerAngle), current.x,
current.y);
LineString vertical = geomFactory.createLineString(new Coordinate[]{new Coordinate(current.x, current.y + halfWidth),
current, new Coordinate(current.x, current.y - halfWidth)});
Geometry transformed = rotationInstance.transform(vertical);
linesList.add((LineString) transformed);
}
// last section
centerCoordinate = coordinates.get(coordinates.size() - 1);
LineSegment l2 = new LineSegment(centerCoordinate, coordinates.get(coordinates.size() - 2));
leftCoordinate = l2.pointAlongOffset(0.0, halfWidth);
rightCoordinate = l2.pointAlongOffset(0.0, -halfWidth);
lineString = geomFactory.createLineString(new Coordinate[]{leftCoordinate, centerCoordinate, rightCoordinate});
linesList.add(lineString);
return linesList;
}
/**
* Returns the section line at a given interval along the line.
*
*
* The returned lines are digitized from left to right and contain also the
* center point.
*
*
* Note that first and last coordinate's section are also added, making it
* likely that the interval between the last two coordinates is less
* than the supplied interval.
*
*
*
* @param line the line to use.
* @param interval the interval to use as distance between coordinates. Has to be > 0.
* @param width the total width of the section.
* @return the list of coordinates.
* @param startFrom if > 0, it defines the initial distance to jump.
* @param endAt if > 0, it defines where to end, even if the line is longer.
* @return the list of sections lines at a given interval.
*/
public static List getSectionsAtInterval( LineString line, double interval, double width, double startFrom,
double endAt ) {
if (interval <= 0) {
throw new IllegalArgumentException("Interval needs to be > 0.");
}
double length = line.getLength();
if (startFrom < 0) {
startFrom = 0.0;
}
if (endAt < 0) {
endAt = length;
}
double halfWidth = width / 2.0;
List linesList = new ArrayList();
LengthIndexedLine indexedLine = new LengthIndexedLine(line);
double runningLength = startFrom;
while( runningLength < endAt ) {
Coordinate centerCoordinate = indexedLine.extractPoint(runningLength);
Coordinate leftCoordinate = indexedLine.extractPoint(runningLength, -halfWidth);
Coordinate rightCoordinate = indexedLine.extractPoint(runningLength, halfWidth);
LineString lineString = geomFactory
.createLineString(new Coordinate[]{leftCoordinate, centerCoordinate, rightCoordinate});
linesList.add(lineString);
runningLength = runningLength + interval;
}
Coordinate centerCoordinate = indexedLine.extractPoint(endAt);
Coordinate leftCoordinate = indexedLine.extractPoint(endAt, -halfWidth);
Coordinate rightCoordinate = indexedLine.extractPoint(endAt, halfWidth);
LineString lineString = geomFactory.createLineString(new Coordinate[]{leftCoordinate, centerCoordinate, rightCoordinate});
linesList.add(lineString);
return linesList;
}
/**
* Pack a list of geometries in a {@link STRtree}.
*
* Note that the tree can't be modified once the query method has been called first.
*
* @param geometries the list of geometries.
* @return the {@link STRtree}.
*/
public static STRtree geometriesToSRTree( List geometries ) {
STRtree tree = new STRtree();
for( Geometry geometry : geometries ) {
tree.insert(geometry.getEnvelopeInternal(), geometry);
}
return tree;
}
public static Quadtree geometriesToQuadTree( List geometries ) {
Quadtree tree = new Quadtree();
for( Geometry geometry : geometries ) {
tree.insert(geometry.getEnvelopeInternal(), geometry);
}
return tree;
}
/**
* {@link Polygon} by {@link LineString} split.
*
* From JTS ml: http://lists.refractions.net/pipermail/jts-devel/2008-September/002666.html
*
* @param polygon the input polygon.
* @param line the input line to use to split.
* @return the list of split polygons.
*/
public static List splitPolygon( Polygon polygon, LineString line ) {
/*
* Use MCIndexNoder to node the polygon and linestring together,
* Polygonizer to polygonize the noded edges, and then PointLocater
* to determine which of the resultant polygons correspond to
* the input polygon.
*/
IntersectionAdder _intersector = new IntersectionAdder(new RobustLineIntersector());
MCIndexNoder mci = new MCIndexNoder();
mci.setSegmentIntersector(_intersector);
NodedSegmentString pSeg = new NodedSegmentString(polygon.getCoordinates(), null);
NodedSegmentString lSeg = new NodedSegmentString(line.getCoordinates(), null);
List nodesSegmentStringList = new ArrayList();
nodesSegmentStringList.add(pSeg);
nodesSegmentStringList.add(lSeg);
mci.computeNodes(nodesSegmentStringList);
Polygonizer polygonizer = new Polygonizer();
List lsList = new ArrayList();
for( Object o : mci.getMonotoneChains() ) {
MonotoneChain mtc = (MonotoneChain) o;
LineString l = gf().createLineString(mtc.getCoordinates());
lsList.add(l);
}
Geometry nodedLineStrings = lsList.get(0);
for( int i = 1; i < lsList.size(); i++ ) {
nodedLineStrings = nodedLineStrings.union(lsList.get(i));
}
polygonizer.add(nodedLineStrings);
@SuppressWarnings("unchecked")
Collection polygons = polygonizer.getPolygons();
List newPolygons = new ArrayList();
PointLocator pl = new PointLocator();
for( Polygon p : polygons ) {
if (pl.locate(p.getInteriorPoint().getCoordinate(), p) == Location.INTERIOR) {
newPolygons.add(p);
}
}
return newPolygons;
}
/**
* Extends or shrinks a rectangle following the ration of a fixed one.
*
* This keeps the center point of the rectangle fixed.
*
* @param fixed the fixed {@link Rectangle2D} to use for the ratio.
* @param toScale the {@link Rectangle2D} to adapt to the ratio of the fixed one.
* @param doShrink if true, the adapted rectangle is shrinked as
* opposed to extended.
*/
public static void scaleToRatio( Rectangle2D fixed, Rectangle2D toScale, boolean doShrink ) {
double origWidth = fixed.getWidth();
double origHeight = fixed.getHeight();
double toAdaptWidth = toScale.getWidth();
double toAdaptHeight = toScale.getHeight();
double scaleWidth = 0;
double scaleHeight = 0;
scaleWidth = toAdaptWidth / origWidth;
scaleHeight = toAdaptHeight / origHeight;
double scaleFactor;
if (doShrink) {
scaleFactor = Math.min(scaleWidth, scaleHeight);
} else {
scaleFactor = Math.max(scaleWidth, scaleHeight);
}
double newWidth = origWidth * scaleFactor;
double newHeight = origHeight * scaleFactor;
double dw = (toAdaptWidth - newWidth) / 2.0;
double dh = (toAdaptHeight - newHeight) / 2.0;
double newX = toScale.getX() + dw;
double newY = toScale.getY() + dh;
double newW = toAdaptWidth - 2 * dw;
double newH = toAdaptHeight - 2 * dh;
toScale.setRect(newX, newY, newW, newH);
}
/**
* Calculates the coeffs of the plane equation: ax+by+cz+d=0 given 3 coordinates.
*
* @param c1 coordinate 1.
* @param c2 coordinate 2.
* @param c3 coordinate 3.
* @return the array of the coeffs [a, b, c, d]
*/
public static double[] getPlaneCoefficientsFrom3Points( Coordinate c1, Coordinate c2, Coordinate c3 ) {
double a = (c2.y - c1.y) * (c3.z - c1.z) - (c3.y - c1.y) * (c2.z - c1.z);
double b = (c2.z - c1.z) * (c3.x - c1.x) - (c3.z - c1.z) * (c2.x - c1.x);
double c = (c2.x - c1.x) * (c3.y - c1.y) - (c3.x - c1.x) * (c2.y - c1.y);
double d = -1.0 * (a * c1.x + b * c1.y + c * c1.z);
return new double[]{a, b, c, d};
}
/**
* Get the intersection coordinate between a line and plane.
*
* The line is defined by 2 3d coordinates and the plane by 3 3d coordinates.
*
* from http://paulbourke.net/geometry/pointlineplane/
*
* @param lC1 line coordinate 1.
* @param lC2 line coordinate 2.
* @param pC1 plane coordinate 1.
* @param pC2 plane coordinate 2.
* @param pC3 plane coordinate 3.
* @return the intersection coordinate or null if the line is parallel to the plane.
*/
public static Coordinate getLineWithPlaneIntersection( Coordinate lC1, Coordinate lC2, Coordinate pC1, Coordinate pC2,
Coordinate pC3 ) {
double[] p = getPlaneCoefficientsFrom3Points(pC1, pC2, pC3);
double denominator = p[0] * (lC1.x - lC2.x) + p[1] * (lC1.y - lC2.y) + p[2] * (lC1.z - lC2.z);
if (denominator == 0.0) {
return null;
}
double u = (p[0] * lC1.x + p[1] * lC1.y + p[2] * lC1.z + p[3]) / //
denominator;
double x = lC1.x + (lC2.x - lC1.x) * u;
double y = lC1.y + (lC2.y - lC1.y) * u;
double z = lC1.z + (lC2.z - lC1.z) * u;
return new Coordinate(x, y, z);
}
/**
* Calculates the angle between line and plane.
*
* http://geogebrawiki.wikispaces.com/3D+Geometry
*
* @param a the 3d point.
* @param d the point of intersection between line and plane.
* @param b the second plane coordinate.
* @param c the third plane coordinate.
* @return the angle in degrees between line and plane.
*/
public static double getAngleBetweenLinePlane( Coordinate a, Coordinate d, Coordinate b, Coordinate c ) {
double[] rAD = {d.x - a.x, d.y - a.y, d.z - a.z};
double[] rDB = {b.x - d.x, b.y - d.y, b.z - d.z};
double[] rDC = {c.x - d.x, c.y - d.y, c.z - d.z};
double[] n = {//
/* */rDB[1] * rDC[2] - rDC[1] * rDB[2], //
-1 * (rDB[0] * rDC[2] - rDC[0] * rDB[2]), //
rDB[0] * rDC[1] - rDC[0] * rDB[1]//
};
double cosNum = n[0] * rAD[0] + n[1] * rAD[1] + n[2] * rAD[2];
double cosDen = sqrt(n[0] * n[0] + n[1] * n[1] + n[2] * n[2]) * sqrt(rAD[0] * rAD[0] + rAD[1] * rAD[1] + rAD[2] * rAD[2]);
double cos90MinAlpha = abs(cosNum / cosDen);
double alpha = 90.0 - toDegrees(acos(cos90MinAlpha));
return alpha;
}
/**
* Get shortest distance from a point in 3d to a plane defined by 3 coordinates.
*
* @param c the point in 3d.
* @param pC1 plane coordinate 1.
* @param pC2 plane coordinate 2.
* @param pC3 plane coordinate 3.
* @return the shortest distance from the point to the plane.
*/
public static double getShortestDistanceFromTriangle( Coordinate c, Coordinate pC1, Coordinate pC2, Coordinate pC3 ) {
double[] p = getPlaneCoefficientsFrom3Points(pC1, pC2, pC3);
double result = (p[0] * c.x + p[1] * c.y + p[2] * c.z + p[3]) / Math.sqrt(p[0] * p[0] + p[1] * p[1] + p[2] * p[2]);
return result;
}
/**
* Uses the cosine rule to find an angle in radiants of a triangle defined by the length of its sides.
*
* The calculated angle is the one between the two adjacent sides a and b.
*
* @param a adjacent side 1 length.
* @param b adjacent side 2 length.
* @param c opposite side length.
* @return the angle in radiants.
*/
public static double getAngleInTriangle( double a, double b, double c ) {
double angle = Math.acos((a * a + b * b - c * c) / (2.0 * a * b));
return angle;
}
/**
* Calculates the angle in degrees between 3 3D coordinates.
*
* The calculated angle is the one placed in vertex c2.
*
* @param c1 first 3D point.
* @param c2 central 3D point.
* @param c3 last 3D point.
* @return the angle between the coordinates in degrees.
*/
public static double angleBetween3D( Coordinate c1, Coordinate c2, Coordinate c3 ) {
double a = distance3d(c2, c1, null);
double b = distance3d(c2, c3, null);
double c = distance3d(c1, c3, null);
double angleInTriangle = getAngleInTriangle(a, b, c);
double degrees = toDegrees(angleInTriangle);
return degrees;
}
/**
* Get the winding rule of a triangle by their coordinates (given in digitized order).
*
* @param A coordinate 1.
* @param B coordinate 2.
* @param C coordinate 3.
* @return -1 if the digitalization is clock wise, else 1.
*/
public static int getTriangleWindingRule( Coordinate A, Coordinate B, Coordinate C ) {
double[] rBA = {B.x - A.x, B.y - A.y, B.z - A.z};
double[] rCA = {C.x - A.x, C.y - A.y, C.z - A.z};
double[] crossProduct = {//
/* */rBA[1] * rCA[2] - rBA[2] * rCA[1], //
-1 * (rBA[0] * rCA[2] - rBA[2] * rCA[0]), //
rBA[0] * rCA[1] - rBA[1] * rCA[0] //
};
return crossProduct[2] > 0 ? 1 : -1;
}
/**
* Get the 3d centroid {@link Coordinate} of a triangle.
*
* @param A coordinate 1.
* @param B coordinate 2.
* @param C coordinate 3.
* @return the centroid coordinate.
*/
public static Coordinate getTriangleCentroid( Coordinate A, Coordinate B, Coordinate C ) {
double cx = (A.x + B.x + C.x) / 3.0;
double cy = (A.y + B.y + C.y) / 3.0;
double cz = (A.z + B.z + C.z) / 3.0;
return new Coordinate(cx, cy, cz);
}
/**
* Scales a {@link Polygon} to have an unitary area.
*
* @param polygon the geometry to scale.
* @return a copy of the scaled geometry.
* @throws Exception
*/
public static Geometry scaleToUnitaryArea( Geometry polygon ) throws Exception {
double area = polygon.getArea();
double scale = sqrt(1.0 / area);
AffineTransform scaleAT = new AffineTransform();
scaleAT.scale(scale, scale);
AffineTransform2D scaleTransform = new AffineTransform2D(scaleAT);
polygon = JTS.transform(polygon, scaleTransform);
return polygon;
}
/**
* Tries to merge multilines when they are snapped properly.
*
* @param multiLines the lines to merge.
* @return the list of lines, ideally containing a single line,merged.
*/
@SuppressWarnings("unchecked")
public static List mergeLinestrings( List multiLines ) {
LineMerger lineMerger = new LineMerger();
for( int i = 0; i < multiLines.size(); i++ ) {
Geometry line = multiLines.get(i);
lineMerger.add(line);
}
Collection merged = lineMerger.getMergedLineStrings();
List mergedList = new ArrayList<>();
for( Geometry geom : merged ) {
mergedList.add((LineString) geom);
}
return mergedList;
}
}