// License: GPL. See LICENSE file for details.
package org.openstreetmap.josm.data.validation.util;
import java.awt.geom.Point2D;
import java.util.ArrayList;
import java.util.Collections;
import java.util.HashSet;
import java.util.List;
import java.util.Map;
import java.util.Set;
import org.openstreetmap.josm.data.coor.EastNorth;
import org.openstreetmap.josm.data.osm.Node;
import org.openstreetmap.josm.data.osm.Way;
import org.openstreetmap.josm.data.validation.OsmValidator;
import org.openstreetmap.josm.tools.CheckParameterUtil;
/**
* Utility class
*
* @author frsantos
*/
public final class ValUtil {
private ValUtil() {
// Hide default constructor for utils classes
}
/**
* Returns the start and end cells of a way.
* @param w The way
* @param cellWays The map with all cells
* @return A list with all the cells the way starts or ends
*/
public static List<List<Way>> getWaysInCell(Way w, Map<Point2D,List<Way>> cellWays) {
if (w.getNodesCount() == 0)
return Collections.emptyList();
Node n1 = w.getNode(0);
Node n2 = w.getNode(w.getNodesCount() - 1);
List<List<Way>> cells = new ArrayList<>(2);
Set<Point2D> cellNodes = new HashSet<>();
Point2D cell;
// First, round coordinates
long x0 = Math.round(n1.getEastNorth().east() * OsmValidator.griddetail);
long y0 = Math.round(n1.getEastNorth().north() * OsmValidator.griddetail);
long x1 = Math.round(n2.getEastNorth().east() * OsmValidator.griddetail);
long y1 = Math.round(n2.getEastNorth().north() * OsmValidator.griddetail);
// Start of the way
cell = new Point2D.Double(x0, y0);
cellNodes.add(cell);
List<Way> ways = cellWays.get(cell);
if (ways == null) {
ways = new ArrayList<>();
cellWays.put(cell, ways);
}
cells.add(ways);
// End of the way
cell = new Point2D.Double(x1, y1);
if (!cellNodes.contains(cell)) {
cellNodes.add(cell);
ways = cellWays.get( cell );
if (ways == null) {
ways = new ArrayList<>();
cellWays.put(cell, ways);
}
cells.add(ways);
}
// Then floor coordinates, in case the way is in the border of the cell.
x0 = (long) Math.floor(n1.getEastNorth().east() * OsmValidator.griddetail);
y0 = (long) Math.floor(n1.getEastNorth().north() * OsmValidator.griddetail);
x1 = (long) Math.floor(n2.getEastNorth().east() * OsmValidator.griddetail);
y1 = (long) Math.floor(n2.getEastNorth().north() * OsmValidator.griddetail);
// Start of the way
cell = new Point2D.Double(x0, y0);
if (!cellNodes.contains(cell)) {
cellNodes.add(cell);
ways = cellWays.get(cell);
if (ways == null) {
ways = new ArrayList<>();
cellWays.put(cell, ways);
}
cells.add(ways);
}
// End of the way
cell = new Point2D.Double(x1, y1);
if (!cellNodes.contains(cell)) {
cellNodes.add(cell);
ways = cellWays.get(cell);
if (ways == null) {
ways = new ArrayList<>();
cellWays.put(cell, ways);
}
cells.add(ways);
}
return cells;
}
/**
* Returns the coordinates of all cells in a grid that a line between 2 nodes intersects with.
*
* @param n1 The first node.
* @param n2 The second node.
* @param gridDetail The detail of the grid. Bigger values give smaller
* cells, but a bigger number of them.
* @return A list with the coordinates of all cells
* @throws IllegalArgumentException if n1 or n2 is {@code null} or without coordinates
*/
public static List<Point2D> getSegmentCells(Node n1, Node n2, double gridDetail) throws IllegalArgumentException {
CheckParameterUtil.ensureParameterNotNull(n1, "n1");
CheckParameterUtil.ensureParameterNotNull(n1, "n2");
return getSegmentCells(n1.getEastNorth(), n2.getEastNorth(), gridDetail);
}
/**
* Returns the coordinates of all cells in a grid that a line between 2 nodes intersects with.
*
* @param en1 The first EastNorth.
* @param en2 The second EastNorth.
* @param gridDetail The detail of the grid. Bigger values give smaller
* cells, but a bigger number of them.
* @return A list with the coordinates of all cells
* @throws IllegalArgumentException if en1 or en2 is {@code null}
* @since 6869
*/
public static List<Point2D> getSegmentCells(EastNorth en1, EastNorth en2, double gridDetail) throws IllegalArgumentException {
CheckParameterUtil.ensureParameterNotNull(en1, "en1");
CheckParameterUtil.ensureParameterNotNull(en2, "en2");
List<Point2D> cells = new ArrayList<>();
double x0 = en1.east() * gridDetail;
double x1 = en2.east() * gridDetail;
double y0 = en1.north() * gridDetail + 1;
double y1 = en2.north() * gridDetail + 1;
if (x0 > x1) {
// Move to 1st-4th cuadrants
double aux;
aux = x0; x0 = x1; x1 = aux;
aux = y0; y0 = y1; y1 = aux;
}
double dx = x1 - x0;
double dy = y1 - y0;
long stepY = y0 <= y1 ? 1 : -1;
long gridX0 = (long) Math.floor(x0);
long gridX1 = (long) Math.floor(x1);
long gridY0 = (long) Math.floor(y0);
long gridY1 = (long) Math.floor(y1);
long maxSteps = (gridX1 - gridX0) + Math.abs(gridY1 - gridY0) + 1;
while ((gridX0 <= gridX1 && (gridY0 - gridY1)*stepY <= 0) && maxSteps-- > 0) {
cells.add( new Point2D.Double(gridX0, gridY0));
// Is the cross between the segment and next vertical line nearer than the cross with next horizontal line?
// Note: segment line formula: y=dy/dx(x-x1)+y1
// Note: if dy < 0, must use *bottom* line. If dy > 0, must use upper line
double scanY = dy/dx * (gridX0 + 1 - x1) + y1 + (dy < 0 ? -1 : 0);
double scanX = dx/dy * (gridY0 + (dy < 0 ? 0 : 1)*stepY - y1) + x1;
double distX = Math.pow(gridX0 + 1 - x0, 2) + Math.pow(scanY - y0, 2);
double distY = Math.pow(scanX - x0, 2) + Math.pow(gridY0 + stepY - y0, 2);
if (distX < distY) {
gridX0 += 1;
} else {
gridY0 += stepY;
}
}
return cells;
}
}