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<ImageEntry>(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            System.err.print("fetching image "+i);
044
045            data.get(i).thumbnail = loadThumb(data.get(i));
046
047            if (Main.isDisplayingMapView()) {
048                layer.updateOffscreenBuffer = true;
049                Main.map.mapView.repaint();
050            }
051        }
052        layer.updateOffscreenBuffer = true;
053        Main.map.mapView.repaint();
054    }
055
056    private BufferedImage loadThumb(ImageEntry entry) {
057        final String cacheIdent = entry.getFile().toString()+":"+maxSize;
058
059        if (!cacheOff) {
060            BufferedImage cached = cache.getImg(cacheIdent);
061            if (cached != null) {
062                Main.debug(" from cache");
063                return cached;
064            }
065        }
066
067        Image img = Toolkit.getDefaultToolkit().createImage(entry.getFile().getPath());
068        tracker.addImage(img, 0);
069        try {
070            tracker.waitForID(0);
071        } catch (InterruptedException e) {
072            Main.error(" InterruptedException while loading thumb");
073            return null;
074        }
075        if (tracker.isErrorID(1) || img.getWidth(null) <= 0 || img.getHeight(null) <= 0) {
076            Main.error(" Invalid image");
077            return null;
078        }
079        Rectangle targetSize = ImageDisplay.calculateDrawImageRectangle(
080                new Rectangle(0, 0, img.getWidth(null), img.getHeight(null)),
081                new Rectangle(0, 0, maxSize, maxSize));
082        BufferedImage scaledBI = new BufferedImage(targetSize.width, targetSize.height, BufferedImage.TYPE_INT_RGB);
083        Graphics2D g = scaledBI.createGraphics();
084        while (!g.drawImage(img, 0, 0, targetSize.width, targetSize.height, null)) {
085            try {
086                Thread.sleep(10);
087            } catch(InterruptedException ie) {
088                Main.warn("InterruptedException while drawing thumb");
089            }
090        }
091        g.dispose();
092        tracker.removeImage(img);
093
094        if (scaledBI.getWidth() <= 0 || scaledBI.getHeight() <= 0) {
095            Main.error(" Invalid image");
096            return null;
097        }
098
099        if (!cacheOff) {
100            cache.saveImg(cacheIdent, scaledBI);
101        }
102
103        return scaledBI;
104    }
105
106}