001// License: GPL. See LICENSE file for details. 002package org.openstreetmap.josm.data.validation.util; 003 004import java.awt.geom.Point2D; 005import java.util.ArrayList; 006import java.util.Collections; 007import java.util.HashSet; 008import java.util.List; 009import java.util.Map; 010import java.util.Set; 011 012import org.openstreetmap.josm.data.osm.Node; 013import org.openstreetmap.josm.data.osm.Way; 014import org.openstreetmap.josm.data.validation.OsmValidator; 015 016/** 017 * Utility class 018 * 019 * @author frsantos 020 */ 021public final class ValUtil { 022 023 private ValUtil() { 024 // Hide default constructor for utils classes 025 } 026 027 /** 028 * Returns the start and end cells of a way. 029 * @param w The way 030 * @param cellWays The map with all cells 031 * @return A list with all the cells the way starts or ends 032 */ 033 public static List<List<Way>> getWaysInCell(Way w, Map<Point2D,List<Way>> cellWays) { 034 if (w.getNodesCount() == 0) 035 return Collections.emptyList(); 036 037 Node n1 = w.getNode(0); 038 Node n2 = w.getNode(w.getNodesCount() - 1); 039 040 List<List<Way>> cells = new ArrayList<List<Way>>(2); 041 Set<Point2D> cellNodes = new HashSet<Point2D>(); 042 Point2D cell; 043 044 // First, round coordinates 045 long x0 = Math.round(n1.getEastNorth().east() * OsmValidator.griddetail); 046 long y0 = Math.round(n1.getEastNorth().north() * OsmValidator.griddetail); 047 long x1 = Math.round(n2.getEastNorth().east() * OsmValidator.griddetail); 048 long y1 = Math.round(n2.getEastNorth().north() * OsmValidator.griddetail); 049 050 // Start of the way 051 cell = new Point2D.Double(x0, y0); 052 cellNodes.add(cell); 053 List<Way> ways = cellWays.get(cell); 054 if (ways == null) { 055 ways = new ArrayList<Way>(); 056 cellWays.put(cell, ways); 057 } 058 cells.add(ways); 059 060 // End of the way 061 cell = new Point2D.Double(x1, y1); 062 if (!cellNodes.contains(cell)) { 063 cellNodes.add(cell); 064 ways = cellWays.get( cell ); 065 if (ways == null) { 066 ways = new ArrayList<Way>(); 067 cellWays.put(cell, ways); 068 } 069 cells.add(ways); 070 } 071 072 // Then floor coordinates, in case the way is in the border of the cell. 073 x0 = (long) Math.floor(n1.getEastNorth().east() * OsmValidator.griddetail); 074 y0 = (long) Math.floor(n1.getEastNorth().north() * OsmValidator.griddetail); 075 x1 = (long) Math.floor(n2.getEastNorth().east() * OsmValidator.griddetail); 076 y1 = (long) Math.floor(n2.getEastNorth().north() * OsmValidator.griddetail); 077 078 // Start of the way 079 cell = new Point2D.Double(x0, y0); 080 if (!cellNodes.contains(cell)) { 081 cellNodes.add(cell); 082 ways = cellWays.get(cell); 083 if (ways == null) { 084 ways = new ArrayList<Way>(); 085 cellWays.put(cell, ways); 086 } 087 cells.add(ways); 088 } 089 090 // End of the way 091 cell = new Point2D.Double(x1, y1); 092 if (!cellNodes.contains(cell)) { 093 cellNodes.add(cell); 094 ways = cellWays.get(cell); 095 if (ways == null) { 096 ways = new ArrayList<Way>(); 097 cellWays.put(cell, ways); 098 } 099 cells.add(ways); 100 } 101 return cells; 102 } 103 104 /** 105 * Returns the coordinates of all cells in a grid that a line between 2 106 * nodes intersects with. 107 * 108 * @param n1 The first node. 109 * @param n2 The second node. 110 * @param gridDetail The detail of the grid. Bigger values give smaller 111 * cells, but a bigger number of them. 112 * @return A list with the coordinates of all cells 113 */ 114 public static List<Point2D> getSegmentCells(Node n1, Node n2, double gridDetail) { 115 List<Point2D> cells = new ArrayList<Point2D>(); 116 double x0 = n1.getEastNorth().east() * gridDetail; 117 double x1 = n2.getEastNorth().east() * gridDetail; 118 double y0 = n1.getEastNorth().north() * gridDetail + 1; 119 double y1 = n2.getEastNorth().north() * gridDetail + 1; 120 121 if (x0 > x1) { 122 // Move to 1st-4th cuadrants 123 double aux; 124 aux = x0; x0 = x1; x1 = aux; 125 aux = y0; y0 = y1; y1 = aux; 126 } 127 128 double dx = x1 - x0; 129 double dy = y1 - y0; 130 long stepY = y0 <= y1 ? 1 : -1; 131 long gridX0 = (long) Math.floor(x0); 132 long gridX1 = (long) Math.floor(x1); 133 long gridY0 = (long) Math.floor(y0); 134 long gridY1 = (long) Math.floor(y1); 135 136 long maxSteps = (gridX1 - gridX0) + Math.abs(gridY1 - gridY0) + 1; 137 while ((gridX0 <= gridX1 && (gridY0 - gridY1)*stepY <= 0) && maxSteps-- > 0) { 138 cells.add( new Point2D.Double(gridX0, gridY0)); 139 140 // Is the cross between the segment and next vertical line nearer than the cross with next horizontal line? 141 // Note: segment line formula: y=dy/dx(x-x1)+y1 142 // Note: if dy < 0, must use *bottom* line. If dy > 0, must use upper line 143 double scanY = dy/dx * (gridX0 + 1 - x1) + y1 + (dy < 0 ? -1 : 0); 144 double scanX = dx/dy * (gridY0 + (dy < 0 ? 0 : 1)*stepY - y1) + x1; 145 146 double distX = Math.pow(gridX0 + 1 - x0, 2) + Math.pow(scanY - y0, 2); 147 double distY = Math.pow(scanX - x0, 2) + Math.pow(gridY0 + stepY - y0, 2); 148 149 if (distX < distY) { 150 gridX0 += 1; 151 } else { 152 gridY0 += stepY; 153 } 154 } 155 return cells; 156 } 157}