kopia lustrzana https://github.com/onthegomap/planetiler
613 wiersze
23 KiB
Java
613 wiersze
23 KiB
Java
/*
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ISC License
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Copyright (c) 2015, Mapbox
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Permission to use, copy, modify, and/or distribute this software for any purpose
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with or without fee is hereby granted, provided that the above copyright notice
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and this permission notice appear in all copies.
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THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES WITH
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REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND
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FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT,
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INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS
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OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
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TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF
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THIS SOFTWARE.
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*/
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package com.onthegomap.planetiler.render;
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import com.carrotsearch.hppc.IntObjectMap;
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import com.carrotsearch.hppc.cursors.IntCursor;
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import com.carrotsearch.hppc.cursors.IntObjectCursor;
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import com.onthegomap.planetiler.collection.Hppc;
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import com.onthegomap.planetiler.collection.IntRangeSet;
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import com.onthegomap.planetiler.geo.GeoUtils;
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import com.onthegomap.planetiler.geo.MutableCoordinateSequence;
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import com.onthegomap.planetiler.geo.TileCoord;
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import com.onthegomap.planetiler.geo.TileExtents;
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import java.util.ArrayList;
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import java.util.Collections;
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import java.util.EnumSet;
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import java.util.HashMap;
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import java.util.List;
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import java.util.Map;
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import java.util.TreeSet;
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import javax.annotation.concurrent.NotThreadSafe;
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import org.locationtech.jts.geom.Coordinate;
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import org.locationtech.jts.geom.CoordinateSequence;
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import org.locationtech.jts.geom.Geometry;
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import org.locationtech.jts.geom.impl.PackedCoordinateSequence;
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import org.slf4j.Logger;
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import org.slf4j.LoggerFactory;
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/**
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* Splits geometries represented by lists of {@link CoordinateSequence CoordinateSequences} into the geometries that
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* appear on individual tiles that the geometry touches.
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* <p>
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* {@link GeometryCoordinateSequences} converts between JTS {@link Geometry} instances and {@link CoordinateSequence}
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* lists for this utility.
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* <p>
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* This class is adapted from the stripe clipping algorithm in https://github.com/mapbox/geojson-vt/ and modified so
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* that it eagerly produces all sliced tiles at a zoom level for each input geometry.
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*/
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@NotThreadSafe
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class TiledGeometry {
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private static final Logger LOGGER = LoggerFactory.getLogger(TiledGeometry.class);
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private static final double NEIGHBOR_BUFFER_EPS = 0.1d / 4096;
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private final long featureId;
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private final Map<TileCoord, List<List<CoordinateSequence>>> tileContents = new HashMap<>();
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/** Map from X coordinate to range of Y coordinates that contain filled tiles inside this geometry */
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private Map<Integer, IntRangeSet> filledRanges = null;
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private final TileExtents.ForZoom extents;
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private final double buffer;
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private final double neighborBuffer;
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private final int z;
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private final boolean area;
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private final int maxTilesAtThisZoom;
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private TiledGeometry(TileExtents.ForZoom extents, double buffer, int z, boolean area, long featureId) {
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this.featureId = featureId;
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this.extents = extents;
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this.buffer = buffer;
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// make sure we inspect neighboring tiles when a line runs along an edge
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this.neighborBuffer = buffer + NEIGHBOR_BUFFER_EPS;
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this.z = z;
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this.area = area;
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this.maxTilesAtThisZoom = 1 << z;
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}
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/**
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* Returns all the points that appear on tiles representing points at {@code coords}.
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*
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* @param extents range of tile coordinates within the bounds of the map to generate
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* @param buffer how far detail should be included beyond the edge of each tile (0=none, 1=a full tile width)
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* @param z zoom level
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* @param coords the world web mercator coordinates of each point to emit at this zoom level where (0,0) is the
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* northwest and (2^z,2^z) is the southeast corner of the planet
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* @param id feature ID
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* @return each tile this feature touches, and the points that appear on each
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*/
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public static TiledGeometry slicePointsIntoTiles(TileExtents.ForZoom extents, double buffer, int z,
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Coordinate[] coords, long id) {
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TiledGeometry result = new TiledGeometry(extents, buffer, z, false, id);
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for (Coordinate coord : coords) {
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result.slicePoint(coord);
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}
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return result;
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}
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private static int wrapInt(int value, int max) {
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value %= max;
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if (value < 0) {
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value += max;
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}
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return value;
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}
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private void slicePoint(Coordinate coord) {
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double worldX = coord.getX() * maxTilesAtThisZoom;
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double worldY = coord.getY() * maxTilesAtThisZoom;
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int minX = (int) Math.floor(worldX - neighborBuffer);
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int maxX = (int) Math.floor(worldX + neighborBuffer);
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int minY = Math.max(extents.minY(), (int) Math.floor(worldY - neighborBuffer));
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int maxY = Math.min(extents.maxY() - 1, (int) Math.floor(worldY + neighborBuffer));
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for (int x = minX; x <= maxX; x++) {
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double tileX = worldX - x;
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int wrappedX = wrapInt(x, maxTilesAtThisZoom);
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// point may end up inside bounds after wrapping
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if (extents.testX(wrappedX)) {
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for (int y = minY; y <= maxY; y++) {
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TileCoord tile = TileCoord.ofXYZ(wrappedX, y, z);
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double tileY = worldY - y;
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tileContents.computeIfAbsent(tile, t -> List.of(new ArrayList<>()))
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.get(0)
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.add(GeoUtils.coordinateSequence(tileX * 256, tileY * 256));
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}
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}
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}
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}
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public int zoomLevel() {
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return z;
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}
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/**
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* Returns all the points that appear on tiles representing points at {@code coords}.
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*
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* @param groups the list of linestrings or polygon rings extracted using {@link GeometryCoordinateSequences} in
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* world web mercator coordinates where (0,0) is the northwest and (2^z,2^z) is the southeast corner of
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* the planet
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* @param buffer how far detail should be included beyond the edge of each tile (0=none, 1=a full tile width)
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* @param area {@code true} if this is a polygon {@code false} if this is a linestring
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* @param z zoom level
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* @param extents range of tile coordinates within the bounds of the map to generate
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* @param id feature ID
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* @return each tile this feature touches, and the points that appear on each
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*/
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public static TiledGeometry sliceIntoTiles(List<List<CoordinateSequence>> groups, double buffer, boolean area, int z,
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TileExtents.ForZoom extents, long id) {
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TiledGeometry result = new TiledGeometry(extents, buffer, z, area, id);
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EnumSet<Direction> wrapResult = result.sliceWorldCopy(groups, 0);
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if (wrapResult.contains(Direction.RIGHT)) {
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result.sliceWorldCopy(groups, -result.maxTilesAtThisZoom);
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}
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if (wrapResult.contains(Direction.LEFT)) {
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result.sliceWorldCopy(groups, result.maxTilesAtThisZoom);
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}
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return result;
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}
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/**
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* Returns an iterator over the coordinates of every tile that is completely filled within this polygon at this zoom
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* level, ordered by x ascending, y ascending.
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*/
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public Iterable<TileCoord> getFilledTiles() {
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return filledRanges == null ? Collections.emptyList() :
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() -> filledRanges.entrySet().stream()
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.<TileCoord>mapMulti((entry, next) -> {
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int x = entry.getKey();
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for (int y : entry.getValue()) {
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TileCoord coord = TileCoord.ofXYZ(x, y, z);
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if (!tileContents.containsKey(coord)) {
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next.accept(coord);
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}
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}
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}).iterator();
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}
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/**
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* Returns every tile that this geometry touches, and the partial geometry contained on that tile that can be
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* reassembled using {@link GeometryCoordinateSequences}.
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*/
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public Iterable<Map.Entry<TileCoord, List<List<CoordinateSequence>>>> getTileData() {
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return tileContents.entrySet();
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}
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private static int wrapX(int x, int max) {
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x %= max;
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if (x < 0) {
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x += max;
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}
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return x;
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}
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/** Adds a new point to {@code out} where the line segment from (ax,ay) to (bx,by) crosses a vertical line at x=x. */
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private static void intersectX(MutableCoordinateSequence out, double ax, double ay, double bx, double by, double x) {
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double t = (x - ax) / (bx - ax);
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out.addPoint(x, ay + (by - ay) * t);
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}
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/**
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* Adds a new point to {@code out} where the line segment from (ax,ay) to (bx,by) crosses a horizontal line at y=y.
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*/
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private static void intersectY(MutableCoordinateSequence out, double ax, double ay, double bx, double by, double y) {
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double t = (y - ay) / (by - ay);
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out.addPoint(ax + (bx - ax) * t, y);
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}
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private static CoordinateSequence fill(double buffer) {
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double min = -256d * buffer;
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double max = 256d - min;
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return new PackedCoordinateSequence.Double(new double[]{
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min, min,
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max, min,
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max, max,
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min, max,
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min, min
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}, 2, 0);
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}
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/**
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* Slices a geometry into tiles and stores in member fields for a single "copy" of the world.
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* <p>
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* Instead of handling content outside -180 to 180 degrees longitude, return {@link Direction#LEFT} or
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* {@link Direction#RIGHT} to indicate whether this method should be called again with a different {@code xOffset} to
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* process wrapped content.
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*
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* @param groups the geometry
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* @param xOffset offset to apply to each X coordinate (-2^z handles content that wraps too far east and 2^z handles
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* content that wraps too far west)
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* @return {@link Direction#LEFT} if there is more content to the west and {@link Direction#RIGHT} if there is more
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* content to the east.
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*/
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private EnumSet<Direction> sliceWorldCopy(List<List<CoordinateSequence>> groups, int xOffset) {
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EnumSet<Direction> overflow = EnumSet.noneOf(Direction.class);
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for (List<CoordinateSequence> group : groups) {
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Map<TileCoord, List<CoordinateSequence>> inProgressShapes = new HashMap<>();
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for (int i = 0; i < group.size(); i++) {
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CoordinateSequence segment = group.get(i);
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boolean isOuterRing = i == 0;
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/*
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* Step 1 in the striped clipping algorithm: slice the geometry into vertical slices representing each "x" tile
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* coordinate:
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* x=0 1 2 3 4 ...
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* | | | | | |
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* |-|-| | | |
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* | | |\| | |
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* | | | |-|-|
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* | | | | | |
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*/
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IntObjectMap<List<MutableCoordinateSequence>> xSlices = sliceX(segment);
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if (z >= 6 && xSlices.size() >= Math.pow(2, z) - 1) {
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LOGGER.warn("Feature " + featureId + " crosses world at z" + z + ": " + xSlices.size());
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}
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for (IntObjectCursor<List<MutableCoordinateSequence>> xCursor : xSlices) {
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int x = xCursor.key + xOffset;
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// skip processing content past the edge of the world, but return that we saw it
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if (x >= maxTilesAtThisZoom) {
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overflow.add(Direction.RIGHT);
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} else if (x < 0) {
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overflow.add(Direction.LEFT);
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} else {
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/*
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* Step 2 in the striped clipping algorithm: split each vertical column x slice into horizontal slices
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* representing the row for each Y coordinate.
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*/
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for (CoordinateSequence stripeSegment : xCursor.value) {
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// sliceY only stores content for rings of a polygon, need to store the
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// filled tiles that it spanned separately
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IntRangeSet filledYRange = sliceY(stripeSegment, x, isOuterRing, inProgressShapes);
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if (area && filledYRange != null) {
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if (isOuterRing) {
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addFilledRange(x, filledYRange);
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} else {
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removeFilledRange(x, filledYRange);
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}
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}
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}
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}
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}
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}
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addShapeToResults(inProgressShapes);
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}
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return overflow;
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}
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private void addShapeToResults(Map<TileCoord, List<CoordinateSequence>> inProgressShapes) {
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for (var entry : inProgressShapes.entrySet()) {
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TileCoord tileID = entry.getKey();
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List<CoordinateSequence> inSeqs = entry.getValue();
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if (area && inSeqs.get(0).size() < 4) {
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// not enough points in outer polygon, ignore
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continue;
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}
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int minPoints = area ? 4 : 2;
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List<CoordinateSequence> outSeqs = inSeqs.stream()
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.filter(seq -> seq.size() >= minPoints)
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.toList();
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if (!outSeqs.isEmpty()) {
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tileContents.computeIfAbsent(tileID, tile -> new ArrayList<>()).add(outSeqs);
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}
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}
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}
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/**
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* Returns a map from X coordinate to segments of this geometry that cross the vertical column formed by all tiles
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* where {@code x=x}.
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*/
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private IntObjectMap<List<MutableCoordinateSequence>> sliceX(CoordinateSequence segment) {
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double leftLimit = -buffer;
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double rightLimit = 1 + buffer;
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IntObjectMap<List<MutableCoordinateSequence>> newGeoms = Hppc.newIntObjectHashMap();
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IntObjectMap<MutableCoordinateSequence> xSlices = Hppc.newIntObjectHashMap();
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int end = segment.size() - 1;
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for (int i = 0; i < end; i++) {
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double ax = segment.getX(i);
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double ay = segment.getY(i);
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double bx = segment.getX(i + 1);
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double by = segment.getY(i + 1);
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double minX = Math.min(ax, bx);
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double maxX = Math.max(ax, bx);
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int startX = (int) Math.floor(minX - neighborBuffer);
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int endX = (int) Math.floor(maxX + neighborBuffer);
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// for each column this segment crosses
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for (int x = startX; x <= endX; x++) {
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double axTile = ax - x;
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double bxTile = bx - x;
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MutableCoordinateSequence slice = xSlices.get(x);
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if (slice == null) {
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xSlices.put(x, slice = new MutableCoordinateSequence());
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List<MutableCoordinateSequence> newGeom = newGeoms.get(x);
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if (newGeom == null) {
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newGeoms.put(x, newGeom = new ArrayList<>());
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}
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newGeom.add(slice);
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}
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boolean exited = false;
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if (axTile < leftLimit) {
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// ---|--> | (line enters the clip region from the left)
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if (bxTile > leftLimit) {
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intersectX(slice, axTile, ay, bxTile, by, leftLimit);
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}
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} else if (axTile > rightLimit) {
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// | <--|--- (line enters the clip region from the right)
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if (bxTile < rightLimit) {
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intersectX(slice, axTile, ay, bxTile, by, rightLimit);
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}
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} else {
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// | --> | (line starts inside)
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slice.addPoint(axTile, ay);
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}
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if (bxTile < leftLimit && axTile >= leftLimit) {
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// <--|--- | or <--|-----|--- (line exits the clip region on the left)
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intersectX(slice, axTile, ay, bxTile, by, leftLimit);
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exited = true;
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}
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if (bxTile > rightLimit && axTile <= rightLimit) {
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// | ---|--> or ---|-----|--> (line exits the clip region on the right)
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intersectX(slice, axTile, ay, bxTile, by, rightLimit);
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exited = true;
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}
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if (!area && exited) {
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xSlices.remove(x);
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}
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}
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}
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// add the last point
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double ax = segment.getX(segment.size() - 1);
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double ay = segment.getY(segment.size() - 1);
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int startX = (int) Math.floor(ax - neighborBuffer);
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int endX = (int) Math.floor(ax + neighborBuffer);
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for (int x = startX - 1; x <= endX + 1; x++) {
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double axTile = ax - x;
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MutableCoordinateSequence slice = xSlices.get(x);
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if (slice != null && axTile >= leftLimit && axTile <= rightLimit) {
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slice.addPoint(axTile, ay);
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}
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}
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// close the polygons if endpoints are not the same after clipping
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if (area) {
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for (IntObjectCursor<MutableCoordinateSequence> cursor : xSlices) {
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cursor.value.closeRing();
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}
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}
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newGeoms.removeAll((x, value) -> {
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int wrapped = wrapX(x, maxTilesAtThisZoom);
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return !extents.testX(wrapped);
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});
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return newGeoms;
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}
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/**
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* Splits an entire vertical X column of edge segments into Y rows that form (X, Y) tile coordinates at this zoom
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* level, stores the result in {@link #tileContents} and returns the Y ranges of filled tile coordinates if this is a
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* polygon.
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*/
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private IntRangeSet sliceY(CoordinateSequence stripeSegment, int x, boolean outer,
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Map<TileCoord, List<CoordinateSequence>> inProgressShapes) {
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if (stripeSegment.size() == 0) {
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return null;
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}
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double leftEdge = -buffer;
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double rightEdge = 1 + buffer;
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TreeSet<Integer> tileYsWithDetail = null;
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IntRangeSet rightFilled = null;
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IntRangeSet leftFilled = null;
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IntObjectMap<MutableCoordinateSequence> ySlices = Hppc.newIntObjectHashMap();
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if (x < 0 || x >= maxTilesAtThisZoom) {
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return null;
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}
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// keep a record of filled tiles that we skipped because an edge of the polygon that gets processed
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// later may intersect the edge of a filled tile, and we'll need to replay all the edges we skipped
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record SkippedSegment(Direction side, int lo, int hi) {}
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List<SkippedSegment> skipped = null;
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for (int i = 0; i < stripeSegment.size() - 1; i++) {
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double ax = stripeSegment.getX(i);
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double ay = stripeSegment.getY(i);
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double bx = stripeSegment.getX(i + 1);
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double by = stripeSegment.getY(i + 1);
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double minY = Math.min(ay, by);
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double maxY = Math.max(ay, by);
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int extentMinY = extents.minY();
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int extentMaxY = extents.maxY();
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int startY = Math.max(extentMinY, (int) Math.floor(minY - neighborBuffer));
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int endStartY = Math.max(extentMinY, (int) Math.floor(minY + neighborBuffer));
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int startEndY = Math.min(extentMaxY - 1, (int) Math.floor(maxY - neighborBuffer));
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int endY = Math.min(extentMaxY - 1, (int) Math.floor(maxY + neighborBuffer));
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// inside a fill if one edge of the polygon runs straight down the right side or up the left side of the column
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boolean onRightEdge = area && ax == bx && ax == rightEdge && by > ay;
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boolean onLeftEdge = area && ax == bx && ax == leftEdge && by < ay;
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for (int y = startY; y <= endY; y++) {
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// skip over filled tiles until we get to the next tile that already has detail on it
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if (area && y > endStartY && y < startEndY) {
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if (onRightEdge || onLeftEdge) {
|
|
if (tileYsWithDetail == null) {
|
|
tileYsWithDetail = new TreeSet<>();
|
|
for (IntCursor cursor : ySlices.keys()) {
|
|
tileYsWithDetail.add(cursor.value);
|
|
}
|
|
}
|
|
Integer next = tileYsWithDetail.ceiling(y);
|
|
int nextNonEdgeTile = next == null ? startEndY : Math.min(next, startEndY);
|
|
int endSkip = nextNonEdgeTile - 1;
|
|
if (skipped == null) {
|
|
skipped = new ArrayList<>();
|
|
}
|
|
// save the Y range that we skipped in case a later edge intersects a filled tile
|
|
skipped.add(new SkippedSegment(
|
|
onLeftEdge ? Direction.LEFT : Direction.RIGHT,
|
|
y,
|
|
endSkip
|
|
));
|
|
|
|
if (rightFilled == null) {
|
|
rightFilled = new IntRangeSet();
|
|
leftFilled = new IntRangeSet();
|
|
}
|
|
(onRightEdge ? rightFilled : leftFilled).add(y, endSkip);
|
|
|
|
y = nextNonEdgeTile;
|
|
}
|
|
}
|
|
|
|
// emit linestring/polygon ring detail
|
|
double topLimit = y - buffer;
|
|
double bottomLimit = y + 1 + buffer;
|
|
MutableCoordinateSequence slice = ySlices.get(y);
|
|
if (slice == null) {
|
|
if (tileYsWithDetail != null) {
|
|
tileYsWithDetail.add(y);
|
|
}
|
|
// X is already relative to tile, but we need to adjust Y
|
|
ySlices.put(y, slice = MutableCoordinateSequence.newScalingSequence(0, y, 256));
|
|
TileCoord tileID = TileCoord.ofXYZ(x, y, z);
|
|
List<CoordinateSequence> toAddTo = inProgressShapes.computeIfAbsent(tileID, tile -> new ArrayList<>());
|
|
|
|
// if this is tile is inside a fill from an outer tile, infer that fill here
|
|
if (area && !outer && toAddTo.isEmpty()) {
|
|
toAddTo.add(fill(buffer));
|
|
}
|
|
toAddTo.add(slice);
|
|
|
|
// if this tile was skipped because we skipped an edge, and now it needs more points,
|
|
// backfill all the edges that we skipped for it
|
|
if (area && leftFilled != null && skipped != null && (leftFilled.contains(y) || rightFilled.contains(y))) {
|
|
for (SkippedSegment skippedSegment : skipped) {
|
|
if (skippedSegment.lo <= y && skippedSegment.hi >= y) {
|
|
double top = y - buffer;
|
|
double bottom = y + 1 + buffer;
|
|
if (skippedSegment.side == Direction.LEFT) {
|
|
slice.addPoint(-buffer, bottom);
|
|
slice.addPoint(-buffer, top);
|
|
} else { // side == RIGHT
|
|
slice.addPoint(1 + buffer, top);
|
|
slice.addPoint(1 + buffer, bottom);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
boolean exited = false;
|
|
|
|
if (ay < topLimit) {
|
|
// ---|--> | (line enters the clip region from the top)
|
|
if (by > topLimit) {
|
|
intersectY(slice, ax, ay, bx, by, topLimit);
|
|
}
|
|
} else if (ay > bottomLimit) {
|
|
// | <--|--- (line enters the clip region from the bottom)
|
|
if (by < bottomLimit) {
|
|
intersectY(slice, ax, ay, bx, by, bottomLimit);
|
|
}
|
|
} else {
|
|
// | --> | (line starts inside the clip region)
|
|
slice.addPoint(ax, ay);
|
|
}
|
|
if (by < topLimit && ay >= topLimit) {
|
|
// <--|--- | or <--|-----|--- (line exits the clip region on the top)
|
|
intersectY(slice, ax, ay, bx, by, topLimit);
|
|
exited = true;
|
|
}
|
|
if (by > bottomLimit && ay <= bottomLimit) {
|
|
// | ---|--> or ---|-----|--> (line exits the clip region on the bottom)
|
|
intersectY(slice, ax, ay, bx, by, bottomLimit);
|
|
exited = true;
|
|
}
|
|
|
|
if (!area && exited) {
|
|
ySlices.remove(y);
|
|
}
|
|
}
|
|
}
|
|
|
|
// add the last point
|
|
int last = stripeSegment.size() - 1;
|
|
double ax = stripeSegment.getX(last);
|
|
double ay = stripeSegment.getY(last);
|
|
int startY = (int) Math.floor(ay - neighborBuffer);
|
|
int endY = (int) Math.floor(ay + neighborBuffer);
|
|
|
|
for (int y = startY - 1; y <= endY + 1; y++) {
|
|
MutableCoordinateSequence slice = ySlices.get(y);
|
|
double k1 = y - buffer;
|
|
double k2 = y + 1 + buffer;
|
|
if (ay >= k1 && ay <= k2 && slice != null) {
|
|
slice.addPoint(ax, ay);
|
|
}
|
|
}
|
|
// close the polygons if endpoints are not the same after clipping
|
|
if (area) {
|
|
for (IntObjectCursor<MutableCoordinateSequence> cursor : ySlices) {
|
|
cursor.value.closeRing();
|
|
}
|
|
}
|
|
// a tile is filled if we skipped over the entire left and right side of it while processing a polygon
|
|
return rightFilled != null ? rightFilled.intersect(leftFilled) : null;
|
|
}
|
|
|
|
private void addFilledRange(int x, IntRangeSet yRange) {
|
|
if (yRange == null) {
|
|
return;
|
|
}
|
|
if (filledRanges == null) {
|
|
filledRanges = new HashMap<>();
|
|
}
|
|
IntRangeSet existing = filledRanges.get(x);
|
|
if (existing == null) {
|
|
filledRanges.put(x, yRange);
|
|
} else {
|
|
existing.addAll(yRange);
|
|
}
|
|
}
|
|
|
|
private void removeFilledRange(int x, IntRangeSet yRange) {
|
|
if (yRange == null) {
|
|
return;
|
|
}
|
|
if (filledRanges == null) {
|
|
filledRanges = new HashMap<>();
|
|
}
|
|
IntRangeSet existing = filledRanges.get(x);
|
|
if (existing != null) {
|
|
existing.removeAll(yRange);
|
|
}
|
|
}
|
|
|
|
private enum Direction {
|
|
RIGHT,
|
|
LEFT
|
|
}
|
|
}
|