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[Geotools-commits] svn - r38731 - trunk/modules/library/main/src/main/java/org/geotools/geometry/jts
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From: <svn...@os...> - 2012-05-15 21:21:37
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Author: mdavis Date: 2012-05-15 14:21:30 -0700 (Tue, 15 May 2012) New Revision: 38731 Added: trunk/modules/library/main/src/main/java/org/geotools/geometry/jts/GeometryBuilder.java Log: GEOT-4145, Added GeometryBuilder for easier creation of JTS geometries Added: trunk/modules/library/main/src/main/java/org/geotools/geometry/jts/GeometryBuilder.java =================================================================== --- trunk/modules/library/main/src/main/java/org/geotools/geometry/jts/GeometryBuilder.java (rev 0) +++ trunk/modules/library/main/src/main/java/org/geotools/geometry/jts/GeometryBuilder.java 2012-05-15 21:21:30 UTC (rev 38731) @@ -0,0 +1,466 @@ +/* + * GeoTools - The Open Source Java GIS Toolkit + * http://geotools.org + * + * (C) 2004-2008, Open Source Geospatial Foundation (OSGeo) + * + * This library is free software; you can redistribute it and/or + * modify it under the terms of the GNU Lesser General Public + * License as published by the Free Software Foundation; + * version 2.1 of the License. + * + * 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 + * Lesser General Public License for more details. + */ +package org.geotools.geometry.jts; + +import com.vividsolutions.jts.geom.CoordinateSequence; +import com.vividsolutions.jts.geom.CoordinateSequenceFactory; +import com.vividsolutions.jts.geom.Geometry; +import com.vividsolutions.jts.geom.GeometryCollection; +import com.vividsolutions.jts.geom.GeometryFactory; +import com.vividsolutions.jts.geom.LineString; +import com.vividsolutions.jts.geom.LinearRing; +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; + +/** + * A builder for {@link Geometry} objects. Primarily intended to + * support fluent programming in test code. + * <p> + * Features include: + * <ul> + * <li>Both 2D and 3D coordinate dimensions are supported + * (assuming the provided {@link CoordinateSequenceFactory} supports them) + * <li>Sequences of ordinate values can be supplied in a number of ways + * <li>Rings do not need to be explicitly closed; a closing point will be + * supplied if needed + * <li>Empty geometries of all types can be created + * <li>Composite geometries are validated to ensure they have a consistent + * GeometryFactory and coordinate sequence dimension + * <p> + * Examples of intended usage are: + * + * <pre> + * GeometryBuilder gb = new GeometryBuilder(geomFact); + * LineString line = gb.linestring(1,2, 3,4); + * Polygon poly = gb.polygon(0,0, 0,1, 1,1, 1,0); + * Polygon box = gb.box(0,0, 1,1); + * Polygon hexagon = gb.circle(0,0, 1,1, 6); + * Polygon polyhole = gb.polygon(gb.linearring(0,0, 0,10, 10,10, 10,0), gb.linearring(1,1, 1,9, 9,9, 9,1)) + * </pre> + * + * @author Martin Davis - OpenGeo + * + */ +public class GeometryBuilder { + + private GeometryFactory geomFact; + + private CoordinateSequenceFactory csFact; + + /** + * Create a new instance using the default {@link GeometryFactory}. + */ + public GeometryBuilder() { + this(new GeometryFactory()); + } + + /** + * Creates a new instance using a provided GeometryFactory. + * + * @param geomFact the factory to use + */ + public GeometryBuilder(GeometryFactory geomFact) { + this.geomFact = geomFact; + csFact = geomFact.getCoordinateSequenceFactory(); + } + + /** + * Creates an empty Point + * + * @return an empty Point + */ + public Point point() { + return geomFact.createPoint(createCS(new double[0], 2)); + } + + /** + * Creates an empty Point with coordinate dimension = 3. + * + * @return an empty Point + */ + public Point pointZ() { + return geomFact.createPoint(createCS(new double[0], 3)); + } + + /** + * Creates a 2D Point. + * + * @param x the X ordinate + * @param y the Y ordinate + * @return a Point + */ + public Point point(double x, double y) { + return geomFact.createPoint(createCS(new double[] { x, y }, 2)); + } + + /** + * Creates a 3D Point. + * + * @param x the X ordinate + * @param y the Y ordinate + * @param z the Z ordinate + * @return a Point + */ + public Point pointZ(double x, double y, double z) { + return geomFact.createPoint(createCS(new double[] { x, y, z }, 3)); + } + + /** + * Creates an empty 2D LineString + * + * @return an empty LineString + */ + public LineString lineString() { + return geomFact.createLineString(createCS(new double[0], 2)); + } + + /** + * Creates an empty 3D LineString + * + * @return an empty LineString + */ + public LineString lineStringZ() { + return geomFact.createLineString(createCS(new double[0], 3)); + } + + /** + * Creates a 2D LineString. + * + * @param ord the XY ordinates + * @return a LineString + */ + public LineString lineString(double... ord) { + return geomFact.createLineString(createCS(ord, 2)); + } + + /** + * Creates a 3D LineString. + * + * @param ord the XYZ ordinates + * @return a LineString + */ + public LineString lineStringZ(double... ord) { + return geomFact.createLineString(createCS(ord, 3)); + } + + /** + * Creates an empty 2D LinearRing + * + * @return an empty LinearRing + */ + public LinearRing linearRing() { + return geomFact.createLinearRing(createRingCS(new double[0], 2)); + } + + /** + * Creates an empty 3D LinearRing + * + * @return an empty LinearRing + */ + public LinearRing linearRingZ() { + return geomFact.createLinearRing(createRingCS(new double[0], 3)); + } + + /** + * Creates a 2D LinearRing. If the supplied coordinate list is not closed, a + * closing coordinate is added. + * + * @param ord + * @return a LinearRing + */ + public LinearRing linearRing(double... ord) { + return geomFact.createLinearRing(createRingCS(ord, 2)); + } + + /** + * Creates a 3D LinearRing. If the supplied coordinate list is not closed, a + * closing coordinate is added. + * + * @param ord the XYZ ordinates + * @return a LinearRing + */ + public LinearRing linearRingZ(double... ord) { + return geomFact.createLinearRing(createRingCS(ord, 3)); + } + + /** + * Creates an empty 2D Polygon. + * + * @return an empty Polygon + */ + public Polygon polygon() { + return geomFact.createPolygon(linearRing(), null); + } + + /** + * Creates an empty 3D Polygon. + * + * @return an empty Polygon + */ + public Polygon polygonZ() { + return geomFact.createPolygon(linearRingZ(), null); + } + + /** + * Creates a Polygon from a list of XY coordinates. + * + * @param ord a list of XY ordinates + * @return a Polygon + */ + public Polygon polygon(double... ord) { + return geomFact.createPolygon(linearRing(ord), null); + } + + /** + * Creates a Polygon from a list of XYZ coordinates. + * + * @param ord a list of XYZ ordinates + * @return a Polygon + */ + public Polygon polygonZ(double... ord) { + return geomFact.createPolygon(linearRingZ(ord), null); + } + + /** + * Creates a Polygon from an exterior ring. The coordinate dimension of the + * Polygon is the dimension of the LinearRing. + * + * @param shell the exterior ring + * @return a Polygon + */ + public Polygon polygon(LinearRing shell) { + return geomFact.createPolygon(shell, null); + } + + /** + * Creates a Polygon with a hole from an exterior ring and an interior ring. + * + * @param shell the exterior ring + * @param hole the interior ring + * @return a Polygon with a hole + */ + public Polygon polygon(LinearRing shell, LinearRing hole) { + return geomFact.createPolygon(shell, new LinearRing[] { hole }); + } + + /** + * Creates a Polygon with a hole from an exterior ring and an interior ring + * supplied by the rings of Polygons. + * + * @param shell the exterior ring + * @param hole the interior ring + * @return a Polygon with a hole + */ + public Polygon polygon(Polygon shell, Polygon hole) { + return geomFact.createPolygon((LinearRing) shell.getExteriorRing(), + new LinearRing[] { (LinearRing) hole.getExteriorRing() }); + } + + /** + * Creates a rectangular 2D Polygon from X and Y bounds. + * + * @param x1 the lower X bound + * @param y1 the lower Y bound + * @param x2 the upper X bound + * @param y2 the upper Y bound + * @return a 2D Polygon + */ + public Polygon box(double x1, double y1, double x2, double y2) { + double[] ord = new double[] { x1, y1, x1, y2, x2, y2, x2, y1, x1, y1 }; + return polygon(ord); + } + + /** + * Creates a rectangular 3D Polygon from X and Y bounds. + * + * @param x1 the lower X bound + * @param y1 the lower Y bound + * @param x2 the upper X bound + * @param y2 the upper Y bound + * @param z the Z value for all coordinates + * @return a 3D Polygon + */ + public Polygon boxZ(double x1, double y1, double x2, double y2, double z) { + double[] ord = new double[] { x1, y1, z, x1, y2, z, x2, y2, z, x2, y1, z, + x1, y1, z }; + return polygonZ(ord); + } + + /** + * Creates an elliptical Polygon from a bounding box with a given number of + * sides. + * + * @param x1 + * @param y1 + * @param x2 + * @param y2 + * @param nsides + * @return a 2D Polygon + */ + public Polygon ellipse(double x1, double y1, double x2, double y2, int nsides) { + double rx = Math.abs(x2 - x1) / 2; + double ry = Math.abs(y2 - y1) / 2; + double cx = Math.min(x1, x2) + rx; + double cy = Math.min(x1, x2) + ry; + + double[] ord = new double[2 * nsides + 2]; + double angInc = 2 * Math.PI / nsides; + // create ring in CW order + for (int i = 0; i < nsides; i++) { + double ang = -(i * angInc); + ord[2 * i] = cx + rx * Math.cos(ang); + ord[2 * i + 1] = cy + ry * Math.sin(ang); + } + ord[2 * nsides] = ord[0]; + ord[2 * nsides + 1] = ord[1]; + return polygon(ord); + } + + /** + * Creates a circular Polygon with a given center, radius and number of sides. + * + * @param x the center X ordinate + * @param y the center Y ordinate + * @param radius the radius + * @param nsides the number of sides + * @return a 2D Polygon + */ + public Polygon circle(double x, double y, double radius, int nsides) { + return ellipse(x - radius, y - radius, x + radius, y + radius, nsides); + } + + /** + * Creates a MultiPoint with 2 2D Points. + * + * @param x1 the X ordinate of the first point + * @param y1 the Y ordinate of the first point + * @param x2 the X ordinate of the second point + * @param y2 the Y ordinate of the second point + * @return A MultiPoint + */ + public MultiPoint multiPoint(double x1, double y1, double x2, double y2) { + return geomFact + .createMultiPoint(new Point[] { point(x1, y1), point(x2, y2) }); + } + + /** + * Creates a MultiPoint with 2 3D Points. + * + * @param x1 the X ordinate of the first point + * @param y1 the Y ordinate of the first point + * @param z1 the Z ordinate of the first point + * @param x2 the X ordinate of the second point + * @param y2 the Y ordinate of the second point + * @param z2 the Z ordinate of the second point + * @return A 3D MultiPoint + */ + public MultiPoint multiPointZ(double x1, double y1, double z1, double x2, + double y2, double z2) { + return geomFact.createMultiPoint(new Point[] { pointZ(x1, y1, z1), + pointZ(x2, y2, z2) }); + } + + /** + * Creates a MultiLineString from a set of LineStrings + * + * @param lines the component LineStrings + * @return a MultiLineString + */ + public MultiLineString multiLineString(LineString... lines) { + return geomFact.createMultiLineString(lines); + } + + /** + * Creates a MultiPolygon from a set of Polygons. + * + * @param polys the component polygons + * @return A MultiPolygon + */ + public MultiPolygon multiPolygon(Polygon... polys) { + return geomFact.createMultiPolygon(polys); + } + + /** + * Creates a GeometryCollection from a set of Geometrys + * + * @param geoms the component Geometrys + * @return a GeometryCollection + */ + public GeometryCollection geometryCollection(Geometry... geoms) { + return geomFact.createGeometryCollection(geoms); + } + + /** + * Tests whether a sequence of ordinates of a given dimension is closed (i.e. + * has the first and last coordinate identical). + * + * @param ord the list of ordinate values + * @param dim the dimension of each coordinate + * @return true if the sequence is closed + */ + private boolean isClosed(double[] ord, int dim) { + int n = ord.length / dim; + if (n == 0) + return true; + + int lastPos = dim * (n - 1); + double lastx = ord[lastPos]; + double lasty = ord[lastPos + 1]; + boolean isClosed = lastx == ord[0] && lasty == ord[1]; + return isClosed; + } + + /** + * @param ord + * @param dim + * @return + */ + private CoordinateSequence createRingCS(double[] ord, int dim) { + if (isClosed(ord, dim)) + return createCS(ord, dim); + double[] ord2 = new double[ord.length + dim]; + System.arraycopy(ord, 0, ord2, 0, ord.length); + // copy first coord to last + int n = ord2.length / dim; + int lastPos = dim * n; + for (int i = 0; i < dim; i++) { + ord2[lastPos + i] = ord2[i]; + } + return createCS(ord2, dim); + } + + /** + * @param ord + * @param dim + * @return + */ + private CoordinateSequence createCS(double[] ord, int dim) { + if (ord.length % dim != 0) + throw new IllegalArgumentException("Ordinate array length " + + ord.length + " is not a multiple of dimension " + dim); + int n = ord.length / dim; + CoordinateSequence cs = csFact.create(n, dim); + for (int i = 0; i < n; i++) { + for (int d = 0; d < dim; d++) + cs.setOrdinate(i, d, ord[dim * i + d]); + } + return cs; + } +} |
