001 //$HeadURL: svn+ssh://jwilden@svn.wald.intevation.org/deegree/base/branches/2.5_testing/src/org/deegree/io/shpapi/SHP2WKS.java $ 002 /*---------------------------------------------------------------------------- 003 This file is part of deegree, http://deegree.org/ 004 Copyright (C) 2001-2009 by: 005 Department of Geography, University of Bonn 006 and 007 lat/lon GmbH 008 009 This library is free software; you can redistribute it and/or modify it under 010 the terms of the GNU Lesser General Public License as published by the Free 011 Software Foundation; either version 2.1 of the License, or (at your option) 012 any later version. 013 This library is distributed in the hope that it will be useful, but WITHOUT 014 ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS 015 FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more 016 details. 017 You should have received a copy of the GNU Lesser General Public License 018 along with this library; if not, write to the Free Software Foundation, Inc., 019 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 020 021 Contact information: 022 023 lat/lon GmbH 024 Aennchenstr. 19, 53177 Bonn 025 Germany 026 http://lat-lon.de/ 027 028 Department of Geography, University of Bonn 029 Prof. Dr. Klaus Greve 030 Postfach 1147, 53001 Bonn 031 Germany 032 http://www.geographie.uni-bonn.de/deegree/ 033 034 e-mail: info@deegree.org 035 ----------------------------------------------------------------------------*/ 036 package org.deegree.io.shpapi; 037 038 import java.util.ArrayList; 039 040 import org.deegree.model.crs.CoordinateSystem; 041 import org.deegree.model.spatialschema.Curve; 042 import org.deegree.model.spatialschema.CurveSegment; 043 import org.deegree.model.spatialschema.GeometryFactory; 044 import org.deegree.model.spatialschema.Point; 045 import org.deegree.model.spatialschema.Position; 046 import org.deegree.model.spatialschema.Surface; 047 import org.deegree.model.spatialschema.SurfaceInterpolation; 048 import org.deegree.model.spatialschema.SurfaceInterpolationImpl; 049 050 /** 051 * the class SHP2WKS transforms a polygon structure read from a shape-file<BR> 052 * into a WKSLinearPolygon specified by the sf-specifications<BR> 053 * 054 * @version $Revision: 18195 $ 055 * @author <a href="mailto:poth@lat-lon.de">Andreas Poth</a> 056 * @author last edited by: $Author: mschneider $ 057 * 058 * @version 1.0. $Revision: 18195 $, $Date: 2009-06-18 17:55:39 +0200 (Do, 18 Jun 2009) $ 059 * 060 * @since 2.0 061 */ 062 public class SHP2WKS { 063 064 /** 065 * method: Point transformPoint(CS_CoordinateSystem srs,<BR> 066 * SHPPoint shppoint))<BR> 067 * transforms a SHPPoint to a WKSGeometry<BR> 068 * gets a point that should be transformed<BR> 069 * 070 * @param crs 071 * @param shppoint 072 * @return the transformed point 073 */ 074 public Point transformPoint( CoordinateSystem crs, SHPPoint shppoint ) { 075 return GeometryFactory.createPoint( shppoint.x, shppoint.y, crs ); 076 } 077 078 /** 079 * method: Point[] transformMultiPoint(CS_CoordinateSystem srs,<BR> 080 * SHPMultiPoint shpmultipoint))<BR> 081 * transforms a SHPMultiPoint to a WKSGeometry<BR> 082 * gets a multipoint that should be transformed<BR> 083 * 084 * @param srs 085 * @param shpmultipoint 086 * @return the transformed points 087 */ 088 public Point[] transformMultiPoint( CoordinateSystem srs, SHPMultiPoint shpmultipoint ) { 089 Point[] gm_points = new Point[shpmultipoint.numPoints]; 090 091 for ( int i = 0; i < shpmultipoint.numPoints; i++ ) 092 gm_points[i] = GeometryFactory.createPoint( shpmultipoint.points[i].x, shpmultipoint.points[i].y, srs ); 093 094 return gm_points; 095 } 096 097 /** 098 * method: Point[][] transformPolyLine(CS_CoordinateSystem srs,<BR> 099 * SHPPolyLine shppolyline))<BR> 100 * transforms a SHPPolyLine to a WKSGeometry<BR> 101 * gets a polyline that should be transformed<BR> 102 * 103 * @param crs 104 * @param shppolyline 105 * @return the transformed line 106 */ 107 public Curve[] transformPolyLine( CoordinateSystem crs, SHPPolyLine shppolyline ) { 108 Curve[] curve = new Curve[shppolyline.numParts]; 109 110 try { 111 for ( int j = 0; j < shppolyline.numParts; j++ ) { 112 Position[] gm_points = new Position[shppolyline.points[j].length]; 113 114 for ( int i = 0; i < shppolyline.points[j].length; i++ ) { 115 gm_points[i] = GeometryFactory.createPosition( shppolyline.points[j][i].x, 116 shppolyline.points[j][i].y ); 117 } 118 119 CurveSegment cs = GeometryFactory.createCurveSegment( gm_points, crs ); 120 curve[j] = GeometryFactory.createCurve( cs ); 121 } 122 } catch ( Exception e ) { 123 e.printStackTrace(); 124 } 125 126 return curve; 127 } 128 129 /** 130 * method: private boolean isInsideRing(Point[] ring, Point point)<BR> 131 * checks if a point is inside a polygon. the algorithm is taken from:<BR> 132 * http://www.ics.uci.edu/~eppstein/161/960307.html#intest<BR> 133 */ 134 private boolean isInsideRing( Position[] ring, Position point ) { 135 int crossings = 0; 136 137 for ( int i = 0; i < ring.length; i++ ) { 138 int z = i + 1; 139 140 if ( ( i + 1 ) >= ring.length ) { 141 z = 0; 142 } 143 144 // check if point.x is between x of vertex i and z of ring 145 if ( ( ring[i].getX() < point.getX() && point.getX() < ring[z].getX() ) 146 || ( ring[i].getX() > point.getX() && point.getX() > ring[z].getX() ) ) { 147 double t = ( point.getX() - ring[z].getX() ) / ( ring[i].getX() - ring[z].getX() ); 148 149 double cy = ( t * ring[i].getY() ) + ( ( 1 - t ) * ring[z].getY() ); 150 151 if ( point.getY() == cy ) { // point is on border of ring 152 return false; 153 } else if ( point.getY() > cy ) { // downwards vertical line through point crosses 154 // ring 155 crossings++; 156 } 157 } 158 159 // check if point.x equals x of vertex i of ring while point.y > ring[i].y 160 if ( ( ring[i].getX() == point.getX() ) && ( ring[i].getY() <= point.getY() ) ) { 161 162 if ( ring[i].getY() == point.getY() ) { // point is on border of ring 163 return false; 164 } 165 166 // find next point on ring with different x 167 // (adjacent points in shapefile can have equal x&y) 168 while ( ring[z].getX() == point.getX() ) { 169 if ( z == i ) { 170 return false; 171 } 172 z += 1; 173 if ( z == ring.length ) { 174 z = 0; 175 } 176 } 177 178 // find previous point on ring with different x 179 int zz = i - 1; 180 if ( zz < 0 ) { 181 zz = ring.length - 1; 182 } 183 while ( ring[zz].getX() == point.getX() ) { 184 if ( zz == i ) { 185 return false; 186 } 187 zz -= 1; 188 if ( zz < 0 ) { 189 zz = ring.length - 1; 190 } 191 } 192 193 // if point.x between previous and next x then crossing 194 if ( ring[z].getX() < point.getX() && point.getX() < ring[zz].getX() || ring[z].getX() > point.getX() 195 && point.getX() > ring[zz].getX() ) { 196 crossings++; 197 } 198 199 } 200 } 201 202 if ( ( crossings % 2 ) != 0 ) { 203 return true; 204 } 205 return false; 206 } 207 208 /** 209 * transforms the SHPPolygon to a WKSGeometry<BR> 210 * gets the polygon that should be transformed<BR> 211 * 212 * @param crs 213 * @param shppolygon 214 * @return the transformed polygon 215 */ 216 public Surface[] transformPolygon( CoordinateSystem crs, SHPPolygon shppolygon ) { 217 ArrayList<Position[]> all_rings = new ArrayList<Position[]>( shppolygon.numRings ); 218 ArrayList<Position[]> outer_rings = new ArrayList<Position[]>( shppolygon.numRings ); 219 ArrayList<Position[]> inner_rings = new ArrayList<Position[]>( shppolygon.numRings ); 220 221 for ( int i = 0; i < shppolygon.numRings; i++ ) { 222 223 Position[] ring = new Position[shppolygon.rings.points[i].length]; 224 225 for ( int k = 0; k < shppolygon.rings.points[i].length; k++ ) { 226 ring[k] = GeometryFactory.createPosition( shppolygon.rings.points[i][k].x, 227 shppolygon.rings.points[i][k].y ); 228 } 229 all_rings.add( ring ); 230 } 231 232 // for every outer ring 233 for ( int i = 0; i < all_rings.size(); i++ ) { 234 Position[] out_ring = all_rings.get( i ); 235 236 boolean inn = false; 237 for ( int j = 0; j < all_rings.size(); j++ ) { 238 if ( i == j ) 239 continue; 240 Position[] inring = all_rings.get( j ); 241 242 // check if one or more points of a inner ring are 243 // within the actual outer ring 244 try { 245 if ( isInsideRing( inring, out_ring[0] ) ) { 246 inn = true; 247 inner_rings.add( out_ring ); 248 break; 249 } 250 } catch ( Exception e ) { 251 e.printStackTrace(); 252 } 253 254 } 255 if ( !inn ) { 256 outer_rings.add( out_ring ); 257 } 258 259 } 260 261 ArrayList<Surface> wkslp = new ArrayList<Surface>( outer_rings.size() ); 262 SurfaceInterpolation si = new SurfaceInterpolationImpl(); 263 for ( int i = 0; i < outer_rings.size(); i++ ) { 264 Position[] out_ring = outer_rings.get( i ); 265 266 int count = inner_rings.size() - 1; 267 ArrayList<Position[]> list = new ArrayList<Position[]>( count + 2 ); 268 // find inner rings of the current outter ring 269 for ( int k = count; k >= 0; k-- ) { 270 Position[] in_ring = inner_rings.get( k ); 271 if ( isInsideRing( out_ring, in_ring[0] ) ) { 272 list.add( inner_rings.remove( k ) ); 273 } 274 } 275 Position[][] inrings = list.toArray( new Position[list.size()][] ); 276 277 try { 278 Surface sur = GeometryFactory.createSurface( out_ring, inrings, si, crs ); 279 wkslp.add( sur ); 280 } catch ( Exception e ) { 281 e.printStackTrace(); 282 } 283 284 } 285 286 return wkslp.toArray( new Surface[wkslp.size()] ); 287 } 288 }