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A MapViewer based on the JXMapViewer component of SwingX-WS.
/*
* MapViewer.java
*
* Created on March 14, 2006, 2:14 PM
*
* To change this template, choose Tools | Template Manager
* and open the template in the editor.
*/
package org.jxmapviewer;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Image;
import java.awt.Insets;
import java.awt.Rectangle;
import java.awt.geom.Point2D;
import java.awt.geom.Rectangle2D;
import java.awt.image.BufferedImage;
import java.beans.DesignMode;
import java.beans.PropertyChangeEvent;
import java.beans.PropertyChangeListener;
import java.net.URL;
import java.util.Set;
import javax.imageio.ImageIO;
import javax.swing.JPanel;
import org.jxmapviewer.painter.AbstractPainter;
import org.jxmapviewer.painter.Painter;
import org.jxmapviewer.viewer.GeoPosition;
import org.jxmapviewer.viewer.Tile;
import org.jxmapviewer.viewer.TileFactory;
import org.jxmapviewer.viewer.TileFactoryInfo;
import org.jxmapviewer.viewer.TileListener;
import org.jxmapviewer.viewer.empty.EmptyTileFactory;
/**
* A tile oriented map component that can easily be used with tile sources
* on the web like Google and Yahoo maps, satellite data such as NASA imagery,
* and also with file based sources like pre-processed NASA images.
* A known map provider can be used with the SLMapServerInfo,
* which will connect to a 2km resolution version of NASA's Blue Marble Next Generation
* imagery. @see SLMapServerInfo for more information.
*
* Note, the JXMapViewer has three center point properties. The addressLocation property
* represents an abstract center of the map. This would usually be something like the first item
* in a search result. It is a {@link GeoPosition}. The centerPosition property represents
* the current center point of the map. If the user pans the map then the centerPosition point will
* change but the addressLocation will not. Calling recenterToAddressLocation() will move the map
* back to that center address. The center property represents the same point as the centerPosition
* property, but as a Point2D in pixel space instead of a GeoPosition in lat/long space. Note that
* the center property is a Point2D in the entire world bitmap, not in the portion of the map currently
* visible. You can use the getViewportBounds() method to find the portion of the map currently visible
* and adjust your calculations accordingly. Changing the center property will change the centerPosition
* property and vice versa. All three properties are bound.
* @author [email protected]
* @see org.jxmapviewer.viewer.bmng.SLMapServerInfo
*/
public class JXMapViewer extends JPanel implements DesignMode
{
private static final long serialVersionUID = -3530746298586937321L;
private final boolean isNegativeYAllowed = true; // maybe rename to isNorthBounded and isSouthBounded?
/**
* The zoom level. Generally a value between 1 and 15 (TODO Is this true for all the mapping worlds? What does this
* mean if some mapping system doesn't support the zoom level?
*/
private int zoomLevel = 1;
/**
* The position, in map coordinates of the center point. This is defined as the distance from the top and
* left edges of the map in pixels. Dragging the map component will change the center position. Zooming in/out will
* cause the center to be recalculated so as to remain in the center of the new "map".
*/
private Point2D center = new Point2D.Double(0, 0);
/**
* Indicates whether or not to draw the borders between tiles. Defaults to false. TODO Generally not very nice
* looking, very much a product of testing Consider whether this should really be a property or not.
*/
private boolean drawTileBorders = false;
/**
* Factory used by this component to grab the tiles necessary for painting the map.
*/
private TileFactory factory;
/**
* The position in latitude/longitude of the "address" being mapped. This is a special coordinate that, when moved,
* will cause the map to be moved as well. It is separate from "center" in that "center" tracks the current center
* (in pixels) of the viewport whereas this will not change when panning or zooming. Whenever the addressLocation is
* changed, however, the map will be repositioned.
*/
private GeoPosition addressLocation;
/**
* The overlay to delegate to for painting the "foreground" of the map component. This would include painting
* waypoints, day/night, etc. Also receives mouse events.
*/
private Painter overlay;
private boolean designTime;
private Image loadingImage;
private boolean restrictOutsidePanning = true;
private boolean horizontalWrapped = true;
/**
* Create a new JXMapViewer. By default it will use the EmptyTileFactory
*/
public JXMapViewer()
{
factory = new EmptyTileFactory();
// setTileFactory(new GoogleTileFactory());
// make a dummy loading image
try
{
URL url = JXMapViewer.class.getResource("/images/loading.png");
this.setLoadingImage(ImageIO.read(url));
}
catch (Exception ex)
{
System.out.println("could not load 'loading.png'");
BufferedImage img = new BufferedImage(16, 16, BufferedImage.TYPE_INT_ARGB);
Graphics2D g2 = img.createGraphics();
g2.setColor(Color.black);
g2.fillRect(0, 0, 16, 16);
g2.dispose();
this.setLoadingImage(img);
}
// setAddressLocation(new GeoPosition(37.392137,-121.950431)); // Sun campus
}
@Override
protected void paintComponent(Graphics g)
{
super.paintComponent(g);
doPaintComponent(g);
}
// the method that does the actual painting
private void doPaintComponent(Graphics g)
{/*
* if (isOpaque() || isDesignTime()) { g.setColor(getBackground()); g.fillRect(0,0,getWidth(),getHeight()); }
*/
if (isDesignTime())
{
// do nothing
}
else
{
int z = getZoom();
Rectangle viewportBounds = getViewportBounds();
drawMapTiles(g, z, viewportBounds);
drawOverlays(z, g, viewportBounds);
}
super.paintBorder(g);
}
/**
* Indicate that the component is being used at design time, such as in a visual editor like NetBeans' Matisse
* @param b indicates if the component is being used at design time
*/
@Override
public void setDesignTime(boolean b)
{
this.designTime = b;
}
/**
* Indicates whether the component is being used at design time, such as in a visual editor like NetBeans' Matisse
* @return boolean indicating if the component is being used at design time
*/
@Override
public boolean isDesignTime()
{
return designTime;
}
/**
* Draw the map tiles. This method is for implementation use only.
* @param g Graphics
* @param zoom zoom level to draw at
* @param viewportBounds the bounds to draw within
*/
protected void drawMapTiles(final Graphics g, final int zoom, Rectangle viewportBounds)
{
int size = getTileFactory().getTileSize(zoom);
Dimension mapSize = getTileFactory().getMapSize(zoom);
// calculate the "visible" viewport area in tiles
int numWide = viewportBounds.width / size + 2;
int numHigh = viewportBounds.height / size + 2;
// TilePoint topLeftTile = getTileFactory().getTileCoordinate(
// new Point2D.Double(viewportBounds.x, viewportBounds.y));
TileFactoryInfo info = getTileFactory().getInfo();
// number of tiles in x direction
int tpx = (int) Math.floor(viewportBounds.getX() / info.getTileSize(0));
// number of tiles in y direction
int tpy = (int) Math.floor(viewportBounds.getY() / info.getTileSize(0));
// TilePoint topLeftTile = new TilePoint(tpx, tpy);
// p("top tile = " + topLeftTile);
// fetch the tiles from the factory and store them in the tiles cache
// attach the tileLoadListener
for (int x = 0; x <= numWide; x++)
{
for (int y = 0; y <= numHigh; y++)
{
int itpx = x + tpx;// topLeftTile.getX();
int itpy = y + tpy;// topLeftTile.getY();
// TilePoint point = new TilePoint(x + topLeftTile.getX(), y + topLeftTile.getY());
// only proceed if the specified tile point lies within the area being painted
if (g.getClipBounds().intersects(
new Rectangle(itpx * size - viewportBounds.x, itpy * size - viewportBounds.y, size, size)))
{
Tile tile = getTileFactory().getTile(itpx, itpy, zoom);
int ox = ((itpx * getTileFactory().getTileSize(zoom)) - viewportBounds.x);
int oy = ((itpy * getTileFactory().getTileSize(zoom)) - viewportBounds.y);
// if the tile is off the map to the north/south, then just don't paint anything
if (isTileOnMap(itpx, itpy, mapSize))
{
if (isOpaque())
{
g.setColor(getBackground());
g.fillRect(ox, oy, size, size);
}
}
else if (tile.isLoaded())
{
g.drawImage(tile.getImage(), ox, oy, null);
}
else
{
Tile superTile = null;
// Use tile at higher zoom level with 200% magnification and if we are not already at max resolution
if( zoom < info.getMaximumZoomLevel() ) {
superTile = getTileFactory().getTile(itpx / 2, itpy / 2, zoom + 1);
}
if ( superTile != null && superTile.isLoaded())
{
int offX = (itpx % 2) * size / 2;
int offY = (itpy % 2) * size / 2;
g.drawImage(superTile.getImage(), ox, oy, ox + size, oy + size, offX, offY, offX + size / 2, offY + size / 2, null);
}
else
{
int imageX = (getTileFactory().getTileSize(zoom) - getLoadingImage().getWidth(null)) / 2;
int imageY = (getTileFactory().getTileSize(zoom) - getLoadingImage().getHeight(null)) / 2;
g.setColor(Color.GRAY);
g.fillRect(ox, oy, size, size);
g.drawImage(getLoadingImage(), ox + imageX, oy + imageY, null);
}
}
if (isDrawTileBorders())
{
g.setColor(Color.black);
g.drawRect(ox, oy, size, size);
g.drawRect(ox + size / 2 - 5, oy + size / 2 - 5, 10, 10);
g.setColor(Color.white);
g.drawRect(ox + 1, oy + 1, size, size);
String text = itpx + ", " + itpy + ", " + getZoom();
g.setColor(Color.BLACK);
g.drawString(text, ox + 10, oy + 30);
g.drawString(text, ox + 10 + 2, oy + 30 + 2);
g.setColor(Color.WHITE);
g.drawString(text, ox + 10 + 1, oy + 30 + 1);
}
}
}
}
}
@SuppressWarnings("unused")
private void drawOverlays(final int zoom, final Graphics g, final Rectangle viewportBounds)
{
if (overlay != null)
{
overlay.paint((Graphics2D) g, this, getWidth(), getHeight());
}
}
@SuppressWarnings("unused")
private boolean isTileOnMap(int x, int y, Dimension mapSize)
{
return !isNegativeYAllowed && y < 0 || y >= mapSize.getHeight();
}
/**
* Sets the map overlay. This is a {@code Painter} which will paint on top of the map. It can be used to draw waypoints,
* lines, or static overlays like text messages.
* @param overlay the map overlay to use
*/
public void setOverlayPainter(Painter overlay)
{
Painter old = getOverlayPainter();
this.overlay = overlay;
PropertyChangeListener listener = new PropertyChangeListener()
{
@Override
public void propertyChange(PropertyChangeEvent evt)
{
if (evt.getNewValue().equals(Boolean.TRUE))
{
repaint();
}
}
};
if (old instanceof AbstractPainter)
{
AbstractPainter ap = (AbstractPainter) old;
ap.removePropertyChangeListener("dirty", listener);
}
if (overlay instanceof AbstractPainter)
{
AbstractPainter ap = (AbstractPainter) overlay;
ap.addPropertyChangeListener("dirty", listener);
}
firePropertyChange("mapOverlay", old, getOverlayPainter());
repaint();
}
/**
* Gets the current map overlay
* @return the current map overlay
*/
public Painter getOverlayPainter()
{
return overlay;
}
/**
* Returns the bounds of the viewport in pixels. This can be used to transform points into the world bitmap
* coordinate space.
* @return the bounds in pixels of the "view" of this map
*/
public Rectangle getViewportBounds()
{
return calculateViewportBounds(getCenter());
}
private Rectangle calculateViewportBounds(Point2D centr)
{
Insets insets = getInsets();
// calculate the "visible" viewport area in pixels
int viewportWidth = getWidth() - insets.left - insets.right;
int viewportHeight = getHeight() - insets.top - insets.bottom;
double viewportX = (centr.getX() - viewportWidth / 2);
double viewportY = (centr.getY() - viewportHeight / 2);
return new Rectangle((int) viewportX, (int) viewportY, viewportWidth, viewportHeight);
}
/**
* Set the current zoom level
* @param zoom the new zoom level
*/
public void setZoom(int zoom)
{
if (zoom == this.zoomLevel)
{
return;
}
TileFactoryInfo info = getTileFactory().getInfo();
// don't repaint if we are out of the valid zoom levels
if (info != null && (zoom < info.getMinimumZoomLevel() || zoom > info.getMaximumZoomLevel()))
{
return;
}
// if(zoom >= 0 && zoom <= 15 && zoom != this.zoom) {
int oldzoom = this.zoomLevel;
Point2D oldCenter = getCenter();
Dimension oldMapSize = getTileFactory().getMapSize(oldzoom);
this.zoomLevel = zoom;
this.firePropertyChange("zoom", oldzoom, zoom);
Dimension mapSize = getTileFactory().getMapSize(zoom);
setCenter(new Point2D.Double(oldCenter.getX() * (mapSize.getWidth() / oldMapSize.getWidth()), oldCenter.getY()
* (mapSize.getHeight() / oldMapSize.getHeight())));
repaint();
}
/**
* Gets the current zoom level
* @return the current zoom level
*/
public int getZoom()
{
return this.zoomLevel;
}
/**
* Gets the current address location of the map. This property does not change when the user pans the map. This
* property is bound.
* @return the current map location (address)
*/
public GeoPosition getAddressLocation()
{
return addressLocation;
}
/**
* Gets the current address location of the map
* @param addressLocation the new address location
*/
public void setAddressLocation(GeoPosition addressLocation)
{
GeoPosition old = getAddressLocation();
this.addressLocation = addressLocation;
setCenter(getTileFactory().geoToPixel(addressLocation, getZoom()));
firePropertyChange("addressLocation", old, getAddressLocation());
repaint();
}
/**
* Re-centers the map to have the current address location be at the center of the map, accounting for the map's
* width and height.
*/
public void recenterToAddressLocation()
{
setCenter(getTileFactory().geoToPixel(getAddressLocation(), getZoom()));
repaint();
}
/**
* Indicates if the tile borders should be drawn. Mainly used for debugging.
* @return the value of this property
*/
public boolean isDrawTileBorders()
{
return drawTileBorders;
}
/**
* Set if the tile borders should be drawn. Mainly used for debugging.
* @param drawTileBorders new value of this drawTileBorders
*/
public void setDrawTileBorders(boolean drawTileBorders)
{
boolean old = isDrawTileBorders();
this.drawTileBorders = drawTileBorders;
firePropertyChange("drawTileBorders", old, isDrawTileBorders());
repaint();
}
/**
* A property indicating the center position of the map
* @param geoPosition the new property value
*/
public void setCenterPosition(GeoPosition geoPosition)
{
GeoPosition oldVal = getCenterPosition();
setCenter(getTileFactory().geoToPixel(geoPosition, zoomLevel));
repaint();
GeoPosition newVal = getCenterPosition();
firePropertyChange("centerPosition", oldVal, newVal);
}
/**
* A property indicating the center position of the map
* @return the current center position
*/
public GeoPosition getCenterPosition()
{
return getTileFactory().pixelToGeo(getCenter(), zoomLevel);
}
/**
* Get the current factory
* @return the current property value
*/
public TileFactory getTileFactory()
{
return factory;
}
/**
* Set the current tile factory (must not be null)
* @param factory the new property value
*/
public void setTileFactory(TileFactory factory)
{
if (factory == null)
throw new NullPointerException("factory must not be null");
this.factory.removeTileListener(tileLoadListener);
this.factory.dispose();
this.factory = factory;
this.setZoom(factory.getInfo().getDefaultZoomLevel());
factory.addTileListener(tileLoadListener);
repaint();
}
/**
* A property for an image which will be display when an image is still loading.
* @return the current property value
*/
public Image getLoadingImage()
{
return loadingImage;
}
/**
* A property for an image which will be display when an image is still loading.
* @param loadingImage the new property value
*/
public void setLoadingImage(Image loadingImage)
{
this.loadingImage = loadingImage;
}
/**
* Gets the current pixel center of the map. This point is in the global bitmap coordinate system, not as lat/longs.
* @return the current center of the map as a pixel value
*/
public Point2D getCenter()
{
return center;
}
/**
* Sets the new center of the map in pixel coordinates.
* @param center the new center of the map in pixel coordinates
*/
public void setCenter(Point2D center)
{
Point2D old = this.getCenter();
double centerX = center.getX();
double centerY = center.getY();
Dimension mapSize = getTileFactory().getMapSize(getZoom());
int mapHeight = (int) mapSize.getHeight() * getTileFactory().getTileSize(getZoom());
int mapWidth = (int) mapSize.getWidth() * getTileFactory().getTileSize(getZoom());
if (isRestrictOutsidePanning())
{
Insets insets = getInsets();
int viewportHeight = getHeight() - insets.top - insets.bottom;
int viewportWidth = getWidth() - insets.left - insets.right;
// don't let the user pan over the top edge
Rectangle newVP = calculateViewportBounds(center);
if (newVP.getY() < 0)
{
centerY = viewportHeight / 2;
}
// don't let the user pan over the left edge
if (!isHorizontalWrapped() && newVP.getX() < 0)
{
centerX = viewportWidth / 2;
}
// don't let the user pan over the bottom edge
if (newVP.getY() + newVP.getHeight() > mapHeight)
{
centerY = mapHeight - viewportHeight / 2;
}
// don't let the user pan over the right edge
if (!isHorizontalWrapped() && (newVP.getX() + newVP.getWidth() > mapWidth))
{
centerX = mapWidth - viewportWidth / 2;
}
// if map is to small then just center it vert
if (mapHeight < newVP.getHeight())
{
centerY = mapHeight / 2;// viewportHeight/2;// - mapHeight/2;
}
// if map is too small then just center it horiz
if (!isHorizontalWrapped() && mapWidth < newVP.getWidth())
{
centerX = mapWidth / 2;
}
}
// If center is outside (0, 0,mapWidth, mapHeight)
// compute modulo to get it back in.
{
centerX = centerX % mapWidth;
centerY = centerY % mapHeight;
if (centerX < 0)
centerX += mapWidth;
if (centerY < 0)
centerY += mapHeight;
}
GeoPosition oldGP = this.getCenterPosition();
this.center = new Point2D.Double(centerX, centerY);
firePropertyChange("center", old, this.center);
firePropertyChange("centerPosition", oldGP, this.getCenterPosition());
repaint();
}
/**
* Calculates a zoom level so that all points in the specified set will be visible on screen. This is useful if you
* have a bunch of points in an area like a city and you want to zoom out so that the entire city and it's points
* are visible without panning.
* @param positions A set of GeoPositions to calculate the new zoom from
*/
public void calculateZoomFrom(Set positions)
{
// u.p("calculating a zoom based on: ");
// u.p(positions);
if (positions.size() < 2)
{
return;
}
int zoom = getZoom();
Rectangle2D rect = generateBoundingRect(positions, zoom);
// Rectangle2D viewport = map.getViewportBounds();
int count = 0;
while (!getViewportBounds().contains(rect))
{
// u.p("not contained");
Point2D centr = new Point2D.Double(rect.getX() + rect.getWidth() / 2, rect.getY() + rect.getHeight() / 2);
GeoPosition px = getTileFactory().pixelToGeo(centr, zoom);
// u.p("new geo = " + px);
setCenterPosition(px);
count++;
if (count > 30)
break;
if (getViewportBounds().contains(rect))
{
// u.p("did it finally");
break;
}
zoom = zoom + 1;
if (zoom > 15) //TODO: use maxZoom of the tfInfo
{
break;
}
setZoom(zoom);
rect = generateBoundingRect(positions, zoom);
}
}
/**
* Zoom and center the map to a best fit around the input GeoPositions.
* Best fit is defined as the most zoomed-in possible view where both
* the width and height of a bounding box around the positions take up
* no more than maxFraction of the viewport width or height respectively.
* @param positions A set of GeoPositions to calculate the new zoom from
* @param maxFraction the maximum fraction of the viewport that should be covered
*/
public void zoomToBestFit(Set positions, double maxFraction)
{
if (positions.isEmpty())
return;
if (maxFraction <= 0 || maxFraction > 1)
throw new IllegalArgumentException("maxFraction must be between 0 and 1");
TileFactory tileFactory = getTileFactory();
TileFactoryInfo info = tileFactory.getInfo();
if(info == null)
return;
// set to central position initially
Rectangle2D bounds=generateBoundingRect(positions, getZoom());
Point2D bc = new Point2D.Double(bounds.getCenterX(),bounds.getCenterY());
GeoPosition centre = tileFactory.pixelToGeo(bc, getZoom());
setCenterPosition(centre);
if (positions.size() == 1)
return;
// set map to maximum zoomed out
setZoom(info.getMaximumZoomLevel());
// repeatedly zoom in until we find the first zoom level where either the width or height
// of the points takes up more than the max fraction of the viewport
int bestZoom = getZoom();
Rectangle2D viewport = getViewportBounds();
while (true)
{
// is this zoom still OK?
bounds = generateBoundingRect(positions, getZoom());
if (bounds.getWidth() < viewport.getWidth() * maxFraction &&
bounds.getHeight() < viewport.getHeight()* maxFraction)
{
bestZoom = getZoom();
}
else
{
break;
}
if (getZoom() == info.getMinimumZoomLevel())
{
break;
}
else
{
setZoom(getZoom()-1);
}
}
setZoom(bestZoom);
}
private Rectangle2D generateBoundingRect(final Set positions, int zoom)
{
Point2D point1 = getTileFactory().geoToPixel(positions.iterator().next(), zoom);
Rectangle2D rect = new Rectangle2D.Double(point1.getX(), point1.getY(), 0, 0);
for (GeoPosition pos : positions)
{
Point2D point = getTileFactory().geoToPixel(pos, zoom);
rect.add(point);
}
return rect;
}
// a property change listener which forces repaints when tiles finish loading
private TileListener tileLoadListener = new TileListener()
{
@Override
public void tileLoaded(Tile tile)
{
if (tile.getZoom() == getZoom())
{
repaint();
/* this optimization doesn't save much and it doesn't work if you
* wrap around the world
Rectangle viewportBounds = getViewportBounds();
TilePoint tilePoint = t.getLocation();
Point point = new Point(tilePoint.getX() * getTileFactory().getTileSize(), tilePoint.getY() * getTileFactory().getTileSize());
Rectangle tileRect = new Rectangle(point, new Dimension(getTileFactory().getTileSize(), getTileFactory().getTileSize()));
if (viewportBounds.intersects(tileRect)) {
//convert tileRect from world space to viewport space
repaint(new Rectangle(
tileRect.x - viewportBounds.x,
tileRect.y - viewportBounds.y,
tileRect.width,
tileRect.height
));
}*/
}
}
};
/**
* @return true if panning is restricted or not
*/
public boolean isRestrictOutsidePanning()
{
return restrictOutsidePanning;
}
/**
* @param restrictOutsidePanning set if panning is restricted or not
*/
public void setRestrictOutsidePanning(boolean restrictOutsidePanning)
{
this.restrictOutsidePanning = restrictOutsidePanning;
}
/**
* @return true if horizontally wrapped or not
*/
public boolean isHorizontalWrapped()
{
return horizontalWrapped;
}
/**
* @param horizontalWrapped true if horizontal wrap is enabled
*/
public void setHorizontalWrapped(boolean horizontalWrapped)
{
this.horizontalWrapped = horizontalWrapped;
}
/**
* Converts the specified GeoPosition to a point in the JXMapViewer's local coordinate space. This method is
* especially useful when drawing lat/long positions on the map.
* @param pos a GeoPosition on the map
* @return the point in the local coordinate space of the map
*/
public Point2D convertGeoPositionToPoint(GeoPosition pos)
{
// convert from geo to world bitmap
Point2D pt = getTileFactory().geoToPixel(pos, getZoom());
// convert from world bitmap to local
Rectangle bounds = getViewportBounds();
return new Point2D.Double(pt.getX() - bounds.getX(), pt.getY() - bounds.getY());
}
/**
* Converts the specified Point2D in the JXMapViewer's local coordinate space to a GeoPosition on the map. This
* method is especially useful for determining the GeoPosition under the mouse cursor.
* @param pt a point in the local coordinate space of the map
* @return the point converted to a GeoPosition
*/
public GeoPosition convertPointToGeoPosition(Point2D pt)
{
// convert from local to world bitmap
Rectangle bounds = getViewportBounds();
Point2D pt2 = new Point2D.Double(pt.getX() + bounds.getX(), pt.getY() + bounds.getY());
// convert from world bitmap to geo
GeoPosition pos = getTileFactory().pixelToGeo(pt2, getZoom());
return pos;
}
/**
* @return isNegativeYAllowed
*/
public boolean isNegativeYAllowed()
{
return isNegativeYAllowed;
}
}