001// License: GPL. See LICENSE file for details.
002package org.openstreetmap.josm.gui.layer.geoimage;
003
004import java.awt.Graphics2D;
005import java.awt.Image;
006import java.awt.MediaTracker;
007import java.awt.Rectangle;
008import java.awt.Toolkit;
009import java.awt.image.BufferedImage;
010import java.util.ArrayList;
011import java.util.List;
012
013import org.openstreetmap.josm.Main;
014import org.openstreetmap.josm.io.CacheFiles;
015
016public class ThumbsLoader implements Runnable {
017    public static final int maxSize = 120;
018    public static final int minSize = 22;
019    volatile boolean stop = false;
020    List<ImageEntry> data;
021    GeoImageLayer layer;
022    MediaTracker tracker;
023    CacheFiles cache;
024    boolean cacheOff = Main.pref.getBoolean("geoimage.noThumbnailCache", false);
025
026    public ThumbsLoader(GeoImageLayer layer) {
027        this.layer = layer;
028        this.data = new ArrayList<>(layer.data);
029        if (!cacheOff) {
030            cache = new CacheFiles("geoimage-thumbnails", false);
031            cache.setExpire(CacheFiles.EXPIRE_NEVER, false);
032            cache.setMaxSize(120, false);
033        }
034    }
035
036    @Override
037    public void run() {
038        Main.debug("Load Thumbnails");
039        tracker = new MediaTracker(Main.map.mapView);
040        for (int i = 0; i < data.size(); i++) {
041            if (stop) return;
042
043            data.get(i).thumbnail = loadThumb(data.get(i));
044
045            if (Main.isDisplayingMapView()) {
046                layer.updateOffscreenBuffer = true;
047                Main.map.mapView.repaint();
048            }
049        }
050        layer.updateOffscreenBuffer = true;
051        Main.map.mapView.repaint();
052    }
053
054    private BufferedImage loadThumb(ImageEntry entry) {
055        final String cacheIdent = entry.getFile().toString()+":"+maxSize;
056
057        if (!cacheOff) {
058            BufferedImage cached = cache.getImg(cacheIdent);
059            if (cached != null) {
060                Main.debug(" from cache");
061                return cached;
062            }
063        }
064
065        Image img = Toolkit.getDefaultToolkit().createImage(entry.getFile().getPath());
066        tracker.addImage(img, 0);
067        try {
068            tracker.waitForID(0);
069        } catch (InterruptedException e) {
070            Main.error(" InterruptedException while loading thumb");
071            return null;
072        }
073        if (tracker.isErrorID(1) || img.getWidth(null) <= 0 || img.getHeight(null) <= 0) {
074            Main.error(" Invalid image");
075            return null;
076        }
077        Rectangle targetSize = ImageDisplay.calculateDrawImageRectangle(
078                new Rectangle(0, 0, img.getWidth(null), img.getHeight(null)),
079                new Rectangle(0, 0, maxSize, maxSize));
080        BufferedImage scaledBI = new BufferedImage(targetSize.width, targetSize.height, BufferedImage.TYPE_INT_RGB);
081        Graphics2D g = scaledBI.createGraphics();
082        while (!g.drawImage(img, 0, 0, targetSize.width, targetSize.height, null)) {
083            try {
084                Thread.sleep(10);
085            } catch(InterruptedException ie) {
086                Main.warn("InterruptedException while drawing thumb");
087            }
088        }
089        g.dispose();
090        tracker.removeImage(img);
091
092        if (scaledBI.getWidth() <= 0 || scaledBI.getHeight() <= 0) {
093            Main.error(" Invalid image");
094            return null;
095        }
096
097        if (!cacheOff) {
098            cache.saveImg(cacheIdent, scaledBI);
099        }
100
101        return scaledBI;
102    }
103
104}