001// License: GPL. For details, see LICENSE file.
002package org.openstreetmap.josm.data.osm.visitor;
003
004import java.util.Collection;
005
006import org.openstreetmap.josm.Main;
007import org.openstreetmap.josm.data.Bounds;
008import org.openstreetmap.josm.data.ProjectionBounds;
009import org.openstreetmap.josm.data.coor.CachedLatLon;
010import org.openstreetmap.josm.data.coor.EastNorth;
011import org.openstreetmap.josm.data.coor.LatLon;
012import org.openstreetmap.josm.data.osm.Node;
013import org.openstreetmap.josm.data.osm.OsmPrimitive;
014import org.openstreetmap.josm.data.osm.Relation;
015import org.openstreetmap.josm.data.osm.RelationMember;
016import org.openstreetmap.josm.data.osm.Way;
017
018/**
019 * Calculates the total bounding rectangle of a series of {@link OsmPrimitive} objects, using the
020 * EastNorth values as reference.
021 * @author imi
022 */
023public class BoundingXYVisitor extends AbstractVisitor {
024
025    private ProjectionBounds bounds;
026
027    @Override
028    public void visit(Node n) {
029        visit(n.getEastNorth());
030    }
031
032    @Override
033    public void visit(Way w) {
034        if (w.isIncomplete()) return;
035        for (Node n : w.getNodes()) {
036            visit(n);
037        }
038    }
039
040    @Override
041    public void visit(Relation e) {
042        // only use direct members
043        for (RelationMember m : e.getMembers()) {
044            if (!m.isRelation()) {
045                m.getMember().accept(this);
046            }
047        }
048    }
049
050    /**
051     * Visiting call for bounds.
052     * @param b bounds
053     */
054    public void visit(Bounds b) {
055        if (b != null) {
056            b.visitEdge(Main.getProjection(), this::visit);
057        }
058    }
059
060    /**
061     * Visiting call for projection bounds.
062     * @param b projection bounds
063     */
064    public void visit(ProjectionBounds b) {
065        if (b != null) {
066            visit(b.getMin());
067            visit(b.getMax());
068        }
069    }
070
071    /**
072     * Visiting call for lat/lon.
073     * @param latlon lat/lon
074     */
075    public void visit(LatLon latlon) {
076        if (latlon != null) {
077            if (latlon instanceof CachedLatLon) {
078                visit(((CachedLatLon) latlon).getEastNorth());
079            } else {
080                visit(Main.getProjection().latlon2eastNorth(latlon));
081            }
082        }
083    }
084
085    /**
086     * Visiting call for east/north.
087     * @param eastNorth east/north
088     */
089    public void visit(EastNorth eastNorth) {
090        if (eastNorth != null) {
091            if (bounds == null) {
092                bounds = new ProjectionBounds(eastNorth);
093            } else {
094                bounds.extend(eastNorth);
095            }
096        }
097    }
098
099    /**
100     * Determines if the visitor has a non null bounds area.
101     * @return {@code true} if the visitor has a non null bounds area
102     * @see ProjectionBounds#hasExtend
103     */
104    public boolean hasExtend() {
105        return bounds != null && bounds.hasExtend();
106    }
107
108    /**
109     * @return The bounding box or <code>null</code> if no coordinates have passed
110     */
111    public ProjectionBounds getBounds() {
112        return bounds;
113    }
114
115    /**
116     * Enlarges the calculated bounding box by 0.002 degrees.
117     * If the bounding box has not been set (<code>min</code> or <code>max</code>
118     * equal <code>null</code>) this method does not do anything.
119     */
120    public void enlargeBoundingBox() {
121        enlargeBoundingBox(Main.pref.getDouble("edit.zoom-enlarge-bbox", 0.002));
122    }
123
124    /**
125     * Enlarges the calculated bounding box by the specified number of degrees.
126     * If the bounding box has not been set (<code>min</code> or <code>max</code>
127     * equal <code>null</code>) this method does not do anything.
128     *
129     * @param enlargeDegree number of degrees to enlarge on each side
130     */
131    public void enlargeBoundingBox(double enlargeDegree) {
132        if (bounds == null)
133            return;
134        LatLon minLatlon = Main.getProjection().eastNorth2latlon(bounds.getMin());
135        LatLon maxLatlon = Main.getProjection().eastNorth2latlon(bounds.getMax());
136        bounds = new ProjectionBounds(
137                Main.getProjection().latlon2eastNorth(new LatLon(
138                        Math.max(-90, minLatlon.lat() - enlargeDegree),
139                        Math.max(-180, minLatlon.lon() - enlargeDegree))),
140                Main.getProjection().latlon2eastNorth(new LatLon(
141                        Math.min(90, maxLatlon.lat() + enlargeDegree),
142                        Math.min(180, maxLatlon.lon() + enlargeDegree))));
143    }
144
145    /**
146     * Enlarges the bounding box up to <code>maxEnlargePercent</code>, depending on
147     * its size. If the bounding box is small, it will be enlarged more in relation
148     * to its beginning size. The larger the bounding box, the smaller the change,
149     * down to the minimum of 1% enlargement.
150     *
151     * Warning: if the bounding box only contains a single node, no expansion takes
152     * place because a node has no width/height. Use <code>enlargeToMinDegrees</code>
153     * instead.
154     *
155     * Example: You specify enlargement to be up to 100%.
156     *
157     *          Bounding box is a small house: enlargement will be 95–100%, i.e.
158     *          making enough space so that the house fits twice on the screen in
159     *          each direction.
160     *
161     *          Bounding box is a large landuse, like a forest: Enlargement will
162     *          be 1–10%, i.e. just add a little border around the landuse.
163     *
164     * If the bounding box has not been set (<code>min</code> or <code>max</code>
165     * equal <code>null</code>) this method does not do anything.
166     *
167     * @param maxEnlargePercent maximum enlargement in percentage (100.0 for 100%)
168     */
169    public void enlargeBoundingBoxLogarithmically(double maxEnlargePercent) {
170        if (bounds == null)
171            return;
172
173        double diffEast = bounds.getMax().east() - bounds.getMin().east();
174        double diffNorth = bounds.getMax().north() - bounds.getMin().north();
175
176        double enlargeEast = Math.min(maxEnlargePercent - 10*Math.log(diffEast), 1)/100;
177        double enlargeNorth = Math.min(maxEnlargePercent - 10*Math.log(diffNorth), 1)/100;
178
179        visit(bounds.getMin().add(-enlargeEast/2, -enlargeNorth/2));
180        visit(bounds.getMax().add(+enlargeEast/2, +enlargeNorth/2));
181    }
182
183    /**
184     * Specify a degree larger than 0 in order to make the bounding box at least
185     * the specified size in width and height. The value is ignored if the
186     * bounding box is already larger than the specified amount.
187     *
188     * If the bounding box has not been set (<code>min</code> or <code>max</code>
189     * equal <code>null</code>) this method does not do anything.
190     *
191     * If the bounding box contains objects and is to be enlarged, the objects
192     * will be centered within the new bounding box.
193     *
194     * @param size minimum width and height in meter
195     */
196    public void enlargeToMinSize(double size) {
197        if (bounds == null)
198            return;
199        // convert size from meters to east/north units
200        double enSize = size * Main.map.mapView.getScale() / Main.map.mapView.getDist100Pixel() * 100;
201        visit(bounds.getMin().add(-enSize/2, -enSize/2));
202        visit(bounds.getMax().add(+enSize/2, +enSize/2));
203    }
204
205    @Override
206    public String toString() {
207        return "BoundingXYVisitor["+bounds+']';
208    }
209
210    /**
211     * Compute the bounding box of a collection of primitives.
212     * @param primitives the collection of primitives
213     */
214    public void computeBoundingBox(Collection<? extends OsmPrimitive> primitives) {
215        if (primitives == null) return;
216        for (OsmPrimitive p: primitives) {
217            if (p == null) {
218                continue;
219            }
220            p.accept(this);
221        }
222    }
223}