com.spatial4j.core.shape.jts.JtsGeometry Maven / Gradle / Ivy
Go to download
Show more of this group Show more artifacts with this name
Show all versions of spatial4j Show documentation
Show all versions of spatial4j Show documentation
Spatial4j is a general purpose spatial / geospatial ASL licensed open-source Java library. It's
core capabilities are 3-fold: to provide common geospatially-aware shapes, to provide distance
calculations and other math, and to read shape formats like WKT and GeoJSON.
/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.spatial4j.core.shape.jts;
import com.spatial4j.core.context.SpatialContext;
import com.spatial4j.core.context.jts.JtsSpatialContext;
import com.spatial4j.core.distance.DistanceUtils;
import com.spatial4j.core.exception.InvalidShapeException;
import com.spatial4j.core.shape.*;
import com.spatial4j.core.shape.Point;
import com.spatial4j.core.shape.impl.PointImpl;
import com.spatial4j.core.shape.impl.RectangleImpl;
import com.vividsolutions.jts.geom.*;
import com.vividsolutions.jts.operation.union.UnaryUnionOp;
import com.vividsolutions.jts.operation.valid.IsValidOp;
import java.util.ArrayList;
import java.util.List;
/**
* Wraps a JTS {@link Geometry} (i.e. may be a polygon or basically anything).
* JTS's does a great deal of the hard work, but there is work here in handling
* dateline wrap.
*/
public class JtsGeometry implements Shape {
private final Geometry geom;//cannot be a direct instance of GeometryCollection as it doesn't support relate()
private final boolean hasArea;
private final Rectangle bbox;
private final JtsSpatialContext ctx;
public JtsGeometry(Geometry geom, JtsSpatialContext ctx, boolean dateline180Check) {
this.ctx = ctx;
//GeometryCollection isn't supported in relate()
if (geom.getClass().equals(GeometryCollection.class))
throw new IllegalArgumentException("JtsGeometry does not support GeometryCollection but does support its subclasses.");
//NOTE: All this logic is fairly expensive. There are some short-circuit checks though.
if (ctx.isGeo()) {
//Unwraps the geometry across the dateline so it exceeds the standard geo bounds (-180 to +180).
if (dateline180Check)
unwrapDateline(geom);//potentially modifies geom
//If given multiple overlapping polygons, fix it by union
geom = unionGeometryCollection(geom);//returns same or new geom
Envelope unwrappedEnv = geom.getEnvelopeInternal();
//Cuts an unwrapped geometry back into overlaid pages in the standard geo bounds.
geom = cutUnwrappedGeomInto360(geom);//returns same or new geom
assert geom.getEnvelopeInternal().getWidth() <= 360;
assert ! geom.getClass().equals(GeometryCollection.class) : "GeometryCollection unsupported";//double check
//note: this bbox may be sub-optimal. If geom is a collection of things near the dateline on both sides then
// the bbox will needlessly span most or all of the globe longitudinally.
// TODO so consider using MultiShape's planned minimal geo bounding box algorithm once implemented.
double envWidth = unwrappedEnv.getWidth();
//adjust minX and maxX considering the dateline and world wrap
double minX, maxX;
if (envWidth >= 360) {
minX = -180;
maxX = 180;
} else {
minX = unwrappedEnv.getMinX();
maxX = DistanceUtils.normLonDEG(unwrappedEnv.getMinX() + envWidth);
}
bbox = new RectangleImpl(minX, maxX, unwrappedEnv.getMinY(), unwrappedEnv.getMaxY(), ctx);
} else {//not geo
Envelope env = geom.getEnvelopeInternal();
bbox = new RectangleImpl(env.getMinX(),env.getMaxX(),env.getMinY(),env.getMaxY(), ctx);
}
geom.getEnvelopeInternal();//ensure envelope is cached internally, which is lazy evaluated. Keeps this thread-safe.
//Check geom validity; use helpful error
// TODO add way to conditionally skip at your peril later
IsValidOp isValidOp = new IsValidOp(geom);
if (!isValidOp.isValid())
throw new InvalidShapeException(isValidOp.getValidationError().toString());
this.geom = geom;
this.hasArea = !((geom instanceof Lineal) || (geom instanceof Puntal));
}
public static SpatialRelation intersectionMatrixToSpatialRelation(IntersectionMatrix matrix) {
if (matrix.isContains())
return SpatialRelation.CONTAINS;
else if (matrix.isCoveredBy())
return SpatialRelation.WITHIN;
else if (matrix.isDisjoint())
return SpatialRelation.DISJOINT;
return SpatialRelation.INTERSECTS;
}
//----------------------------------------
//----------------------------------------
@Override
public boolean hasArea() {
return hasArea;
}
@Override
public double getArea(SpatialContext ctx) {
double geomArea = geom.getArea();
if (ctx == null || geomArea == 0)
return geomArea;
//Use the area proportional to how filled the bbox is.
double bboxArea = getBoundingBox().getArea(null);//plain 2d area
assert bboxArea >= geomArea;
double filledRatio = geomArea / bboxArea;
return getBoundingBox().getArea(ctx) * filledRatio;
// (Future: if we know we use an equal-area projection then we don't need to
// estimate)
}
@Override
public Rectangle getBoundingBox() {
return bbox;
}
@Override
public JtsPoint getCenter() {
return new JtsPoint(geom.getCentroid(), ctx);
}
@Override
public SpatialRelation relate(Shape other) {
if (other instanceof Point)
return relate((Point)other);
else if (other instanceof Rectangle)
return relate((Rectangle) other);
else if (other instanceof Circle)
return relate((Circle) other);
else if (other instanceof JtsGeometry)
return relate((JtsGeometry) other);
return other.relate(this).transpose();
}
public SpatialRelation relate(Point pt) {
//TODO if not jtsPoint, test against bbox to avoid JTS if disjoint
JtsPoint jtsPoint = (JtsPoint) (pt instanceof JtsPoint ? pt : ctx.makePoint(pt.getX(), pt.getY()));
return geom.disjoint(jtsPoint.getGeom()) ? SpatialRelation.DISJOINT : SpatialRelation.CONTAINS;
}
public SpatialRelation relate(Rectangle rectangle) {
SpatialRelation bboxR = bbox.relate(rectangle);
if (bboxR == SpatialRelation.WITHIN || bboxR == SpatialRelation.DISJOINT)
return bboxR;
Geometry oGeom = ctx.getGeometryFrom(rectangle);
return intersectionMatrixToSpatialRelation(geom.relate(oGeom));
}
public SpatialRelation relate(Circle circle) {
SpatialRelation bboxR = bbox.relate(circle);
if (bboxR == SpatialRelation.WITHIN || bboxR == SpatialRelation.DISJOINT)
return bboxR;
//Test each point to see how many of them are outside of the circle.
//TODO consider instead using geom.apply(CoordinateSequenceFilter) -- maybe faster since avoids Coordinate[] allocation
Coordinate[] coords = geom.getCoordinates();
int outside = 0;
int i = 0;
for (Coordinate coord : coords) {
i++;
SpatialRelation sect = circle.relate(new PointImpl(coord.x, coord.y, ctx));
if (sect == SpatialRelation.DISJOINT)
outside++;
if (i != outside && outside != 0)//short circuit: partially outside, partially inside
return SpatialRelation.INTERSECTS;
}
if (i == outside) {
return (relate(circle.getCenter()) == SpatialRelation.DISJOINT)
? SpatialRelation.DISJOINT : SpatialRelation.CONTAINS;
}
assert outside == 0;
return SpatialRelation.WITHIN;
}
public SpatialRelation relate(JtsGeometry jtsGeometry) {
Geometry oGeom = jtsGeometry.geom;
//don't bother checking bbox since geom.relate() does this already
return intersectionMatrixToSpatialRelation(geom.relate(oGeom));
}
@Override
public String toString() {
return geom.toString();
}
@Override
public boolean equals(Object o) {
if (this == o) return true;
if (o == null || getClass() != o.getClass()) return false;
JtsGeometry that = (JtsGeometry) o;
return geom.equalsExact(that.geom);//fast equality for normalized geometries
}
@Override
public int hashCode() {
//FYI if geometry.equalsExact(that.geometry), then their envelopes are the same.
return geom.getEnvelopeInternal().hashCode();
}
public Geometry getGeom() {
return geom;
}
/**
* If geom spans the dateline, then this modifies it to be a
* valid JTS geometry that extends to the right of the standard -180 to +180
* width such that some points are greater than +180 but some remain less.
* Takes care to invoke {@link com.vividsolutions.jts.geom.Geometry#geometryChanged()}
* if needed.
*
* @return The number of times the geometry spans the dateline. >= 0
*/
private static int unwrapDateline(Geometry geom) {
if (geom.getEnvelopeInternal().getWidth() < 180)
return 0;//can't possibly cross the dateline
final int[] result = {0};//an array so that an inner class can modify it.
geom.apply(new GeometryFilter() {
@Override
public void filter(Geometry geom) {
int cross = 0;
if (geom instanceof LineString) {//note: LinearRing extends LineString
if (geom.getEnvelopeInternal().getWidth() < 180)
return;//can't possibly cross the dateline
cross = unwrapDateline((LineString) geom);
} else if (geom instanceof Polygon) {
if (geom.getEnvelopeInternal().getWidth() < 180)
return;//can't possibly cross the dateline
cross = unwrapDateline((Polygon) geom);
} else
return;
result[0] = Math.max(result[0], cross);
}
});//geom.apply()
int crossings = result[0];
return crossings;
}
/** See {@link #unwrapDateline(Geometry)}. */
private static int unwrapDateline(Polygon poly) {
LineString exteriorRing = poly.getExteriorRing();
int cross = unwrapDateline(exteriorRing);
if (cross > 0) {
for(int i = 0; i < poly.getNumInteriorRing(); i++) {
LineString innerLineString = poly.getInteriorRingN(i);
unwrapDateline(innerLineString);
for(int shiftCount = 0; ! exteriorRing.contains(innerLineString); shiftCount++) {
if (shiftCount > cross)
throw new IllegalArgumentException("The inner ring doesn't appear to be within the exterior: "
+exteriorRing+" inner: "+innerLineString);
shiftGeomByX(innerLineString, 360);
}
}
poly.geometryChanged();
}
return cross;
}
/** See {@link #unwrapDateline(Geometry)}. */
private static int unwrapDateline(LineString lineString) {
CoordinateSequence cseq = lineString.getCoordinateSequence();
int size = cseq.size();
if (size <= 1)
return 0;
int shiftX = 0;//invariant: == shiftXPage*360
int shiftXPage = 0;
int shiftXPageMin = 0/* <= 0 */, shiftXPageMax = 0; /* >= 0 */
double prevX = cseq.getX(0);
for(int i = 1; i < size; i++) {
double thisX_orig = cseq.getX(i);
assert thisX_orig >= -180 && thisX_orig <= 180 : "X not in geo bounds";
double thisX = thisX_orig + shiftX;
if (prevX - thisX > 180) {//cross dateline from left to right
thisX += 360;
shiftX += 360;
shiftXPage += 1;
shiftXPageMax = Math.max(shiftXPageMax,shiftXPage);
} else if (thisX - prevX > 180) {//cross dateline from right to left
thisX -= 360;
shiftX -= 360;
shiftXPage -= 1;
shiftXPageMin = Math.min(shiftXPageMin,shiftXPage);
}
if (shiftXPage != 0)
cseq.setOrdinate(i, CoordinateSequence.X, thisX);
}
if (lineString instanceof LinearRing) {
assert cseq.getCoordinate(0).equals(cseq.getCoordinate(size-1));
assert shiftXPage == 0;//starts and ends at 0
}
assert shiftXPageMax >= 0 && shiftXPageMin <= 0;
//Unfortunately we are shifting again; it'd be nice to be smarter and shift once
shiftGeomByX(lineString, shiftXPageMin * -360);
int crossings = shiftXPageMax - shiftXPageMin;
if (crossings > 0)
lineString.geometryChanged();
return crossings;
}
private static void shiftGeomByX(Geometry geom, final int xShift) {
if (xShift == 0)
return;
geom.apply(new CoordinateSequenceFilter() {
@Override
public void filter(CoordinateSequence seq, int i) {
seq.setOrdinate(i, CoordinateSequence.X, seq.getX(i) + xShift );
}
@Override public boolean isDone() { return false; }
@Override public boolean isGeometryChanged() { return true; }
});
}
private static Geometry unionGeometryCollection(Geometry geom) {
if (geom instanceof GeometryCollection) {
return geom.union();
}
return geom;
}
/**
* This "pages" through standard geo boundaries offset by multiples of 360
* longitudinally that intersect geom, and the intersecting results of a page
* and the geom are shifted into the standard -180 to +180 and added to a new
* geometry that is returned.
*/
private static Geometry cutUnwrappedGeomInto360(Geometry geom) {
Envelope geomEnv = geom.getEnvelopeInternal();
if (geomEnv.getMinX() >= -180 && geomEnv.getMaxX() <= 180)
return geom;
assert geom.isValid() : "geom";
//TODO support geom's that start at negative pages; will avoid need to previously shift in unwrapDateline(geom).
List geomList = new ArrayList();
//page 0 is the standard -180 to 180 range
for (int page = 0; true; page++) {
double minX = -180 + page * 360;
if (geomEnv.getMaxX() <= minX)
break;
Geometry rect = geom.getFactory().toGeometry(new Envelope(minX, minX + 360, -90, 90));
assert rect.isValid() : "rect";
Geometry pageGeom = rect.intersection(geom);//JTS is doing some hard work
assert pageGeom.isValid() : "pageGeom";
shiftGeomByX(pageGeom, page * -360);
geomList.add(pageGeom);
}
return UnaryUnionOp.union(geomList);
}
// private static Geometry removePolyHoles(Geometry geom) {
// //TODO this does a deep copy of geom even if no changes needed; be smarter
// GeometryTransformer gTrans = new GeometryTransformer() {
// @Override
// protected Geometry transformPolygon(Polygon geom, Geometry parent) {
// if (geom.getNumInteriorRing() == 0)
// return geom;
// return factory.createPolygon((LinearRing) geom.getExteriorRing(),null);
// }
// };
// return gTrans.transform(geom);
// }
//
// private static Geometry snapAndClean(Geometry geom) {
// return new GeometrySnapper(geom).snapToSelf(GeometrySnapper.computeOverlaySnapTolerance(geom), true);
// }
}
© 2015 - 2025 Weber Informatics LLC | Privacy Policy