Index: utils/josm/plugins/grid/build.xml
===================================================================
--- utils/josm/plugins/grid/build.xml	(revision 1484)
+++ utils/josm/plugins/grid/build.xml	(revision 1484)
@@ -0,0 +1,40 @@
+<project name="grid" default="build" basedir=".">
+
+	<!-- point to your JOSM directory -->
+	<property name="josm" location="../../../../editors/josm/dist/josm-custom.jar" />
+
+
+
+	<target name="init">
+		<mkdir dir="build"></mkdir>
+		<mkdir dir="dist"></mkdir>
+	</target>
+
+	<target name="compile" depends="init">
+		<javac srcdir="src" classpath="${josm}" debug="true" destdir="build">
+			<include name="**/*.java" />
+		</javac>
+	</target>
+
+	<target name="build" depends="compile">
+		<copy todir="build/images" >
+			<fileset dir="images" />
+		</copy>
+		<jar destfile="dist/grid.jar" basedir="build">
+			<manifest>
+				<attribute name="Plugin-Class" value="grid.GridPlugin" />
+				<attribute name="Plugin-Description" value="Provide a background layer that displays a map grid" />
+			</manifest>
+		</jar>
+	</target>
+
+	<target name="clean">
+		<delete dir="build" />
+		<delete dir="dist" />
+	</target>
+
+	<target name="install" depends="build">
+		<copy file="dist/grid.jar" todir="${user.home}/.josm/plugins"/>
+	</target>
+
+</project>
Index: utils/josm/plugins/grid/src/grid/GridLayer.java
===================================================================
--- utils/josm/plugins/grid/src/grid/GridLayer.java	(revision 1484)
+++ utils/josm/plugins/grid/src/grid/GridLayer.java	(revision 1484)
@@ -0,0 +1,169 @@
+package grid;
+
+import static org.openstreetmap.josm.tools.I18n.tr;
+
+import java.awt.Component;
+import java.awt.Graphics;
+import java.awt.Color;
+import java.awt.Point;
+import java.awt.Font;
+import java.awt.FontMetrics;
+import java.awt.Toolkit;
+import java.io.IOException;
+import java.text.NumberFormat;
+
+import java.awt.event.ActionEvent;
+import javax.swing.AbstractAction;
+import javax.swing.Icon;
+import javax.swing.ImageIcon;
+import javax.swing.JMenuItem;
+import javax.swing.JSeparator;
+
+import org.openstreetmap.josm.Main;
+import org.openstreetmap.josm.data.coor.EastNorth;
+import org.openstreetmap.josm.data.coor.LatLon;
+import org.openstreetmap.josm.gui.NavigatableComponent;
+import org.openstreetmap.josm.data.osm.visitor.BoundingXYVisitor;
+import org.openstreetmap.josm.data.projection.Projection;
+import org.openstreetmap.josm.gui.MapView;
+import org.openstreetmap.josm.gui.dialogs.LayerListDialog;
+import org.openstreetmap.josm.gui.dialogs.LayerListPopup;
+import org.openstreetmap.josm.gui.layer.Layer;
+
+/**
+ * This is a layer that draws a grid
+ */
+public class GridLayer extends Layer {
+
+	private static Icon icon = new ImageIcon(Toolkit.getDefaultToolkit().createImage(GridPlugin.class.getResource("/images/grid.png")));
+        private LatLon origin, pole;
+    private float gridunits;
+    private boolean drawLabels;
+
+    	public GridLayer(String url) {
+	    super(url.indexOf('/') != -1 ? url.substring(url.indexOf('/')+1) : url);
+	    origin = new LatLon(0.0,0.0);
+	    pole = new LatLon(0.0,90.0);
+	    drawLabels = true;
+	}
+
+    private void setGrid(LatLon origin, LatLon pole){
+	this.origin = origin;
+	this.pole = pole;
+	//need to chech pole is perpendicular from origin;
+    }
+    private void toggleLabels(){
+	drawLabels=!drawLabels;
+    }
+    private class toggleLabelsAction extends AbstractAction {
+	GridLayer layer;
+	public toggleLabelsAction(GridLayer layer) {
+	    super("show labels");
+	    this.layer = layer;
+	}
+	public void actionPerformed(ActionEvent e) {
+	    layer.toggleLabels();
+	}
+    }
+
+	@Override public Icon getIcon() {
+		return icon;
+	}
+
+	@Override public String getToolTipText() {
+		return tr("Grid layer:" + origin);
+	}
+
+	@Override public boolean isMergable(Layer other) {
+		return false;
+	}
+
+	@Override public void mergeFrom(Layer from) {
+	}
+
+	@Override public void paint(Graphics g, final MapView mv) {
+	    //draw grid here?
+
+	    //establish viewport size
+	    int w = mv.getWidth();
+	    int h = mv.getHeight();
+	    
+	    //establish viewport world coordinates
+	    LatLon tl = mv.getLatLon(0,0);
+	    LatLon br = mv.getLatLon(w,h);
+
+	    //establish max visible grid coordinates (currently also world coordinates)
+	    double minlat = Math.max(Math.min(tl.lat(),br.lat()),-Main.proj.MAX_LAT);
+	    double maxlat = Math.min(Math.max(tl.lat(),br.lat()), Main.proj.MAX_LAT);
+	    double minlon = Math.max(Math.min(tl.lon(),br.lon()),-Main.proj.MAX_LON);
+	    double maxlon = Math.min(Math.max(tl.lon(),br.lon()), Main.proj.MAX_LON);
+
+	    //span is maximum lat/lon span across visible grid normalised to 800pixels
+	    double span = Math.max((maxlat-minlat),(maxlon-minlon))
+		* 800.0/Math.max(h,w);
+
+	    //grid spacing is power of ten to use for grid interval.
+	    double spacing = Math.pow(10,Math.floor(Math.log(span)/Math.log(10.0))-1.0);
+
+	    //set up stuff need to draw grid
+	    NumberFormat nf = NumberFormat.getInstance();
+	    Color majcol = Color.RED;
+	    Color mincol = (majcol.darker()).darker();
+
+
+	    System.out.println("Span: "+span);
+	    System.out.println("Spacing: "+spacing);
+	    g.setFont (new Font("Helvetica", Font.PLAIN, 8));
+	    FontMetrics fm = g.getFontMetrics();
+
+	    for(double lat=spacing*Math.floor(minlat/spacing);lat<maxlat;lat+=spacing){
+		for(double lon=spacing*Math.floor(minlon/spacing);lon<maxlon;lon+=spacing){
+		    LatLon ll0, lli, llj; 
+		    ll0 = new LatLon(lat,lon);
+		    lli = new LatLon(lat+spacing,lon);
+		    llj = new LatLon(lat,lon+spacing);
+		    Point p0=mv.getPoint(Main.proj.latlon2eastNorth(ll0));
+		    Point pi=mv.getPoint(Main.proj.latlon2eastNorth(lli));
+		    Point pj=mv.getPoint(Main.proj.latlon2eastNorth(llj));
+
+		    if(Math.round(lon/spacing)%10==0)
+			g.setColor(majcol);
+		    else
+			g.setColor(mincol);
+		    g.drawLine(p0.x,p0.y,pi.x,pi.y);
+
+		    if(Math.round(lat/spacing)%10==0)
+			g.setColor(majcol);
+		    else
+			g.setColor(mincol);
+		    g.drawLine(p0.x,p0.y,pj.x,pj.y);
+
+		    if((Math.round(lon/spacing))%10==0 && (Math.round(lat/spacing))%10==0 && drawLabels){
+			String label = nf.format(lat);
+			int tw = fm.stringWidth(label); 
+			g.drawString(label,p0.x-tw,p0.y-8);
+			label = nf.format(lon);
+			g.drawString(label,p0.x+2,p0.y+8);
+		    }
+		}		
+	    }
+
+	}
+
+	@Override public void visitBoundingBox(BoundingXYVisitor v) {
+		// doesn't have a bounding box
+	}
+
+	@Override public Object getInfoComponent() {
+		return getToolTipText();
+	}
+
+	@Override public Component[] getMenuEntries() {
+		return new Component[]{
+				new JMenuItem(new LayerListDialog.ShowHideLayerAction(this)),
+				new JMenuItem(new LayerListDialog.DeleteLayerAction(this)),
+				new JMenuItem(new toggleLabelsAction(this)),
+				new JSeparator(),
+				new JMenuItem(new LayerListPopup.InfoAction(this))};
+	}
+}
Index: utils/josm/plugins/grid/src/grid/GridPlugin.java
===================================================================
--- utils/josm/plugins/grid/src/grid/GridPlugin.java	(revision 1484)
+++ utils/josm/plugins/grid/src/grid/GridPlugin.java	(revision 1484)
@@ -0,0 +1,71 @@
+package grid;
+
+import static org.openstreetmap.josm.tools.I18n.tr;
+
+import java.awt.event.ActionEvent;
+import javax.swing.AbstractAction;
+import javax.swing.JMenu;
+import javax.swing.JMenuBar;
+import javax.swing.JMenuItem;
+import javax.swing.JOptionPane;
+
+import org.openstreetmap.josm.Main;
+import org.openstreetmap.josm.data.Bounds;
+import org.openstreetmap.josm.data.coor.LatLon;
+import org.openstreetmap.josm.data.osm.DataSet;
+import org.openstreetmap.josm.data.osm.Node;
+import org.openstreetmap.josm.data.osm.Segment;
+import org.openstreetmap.josm.data.osm.Way;
+import org.openstreetmap.josm.data.osm.visitor.AddVisitor;
+import org.openstreetmap.josm.gui.MapFrame;
+import org.openstreetmap.josm.io.OsmWriter;
+import org.openstreetmap.josm.plugins.Plugin;
+
+public class GridPlugin extends Plugin {
+
+    private class Action extends AbstractAction {
+	public Action() {
+	    super("add grid");
+	}
+	public void actionPerformed(ActionEvent e) {
+	    GridLayer gridLayer = new GridLayer("");
+	    if (gridLayer != null)
+			Main.main.addLayer(gridLayer);
+	}
+    }
+    private JMenu edit;
+    private JMenuItem addGridMenu = new JMenuItem(new Action());
+    
+    public GridPlugin() {
+	JMenuBar menu = Main.main.menu;
+	edit = null;
+	for (int i = 0; i < menu.getMenuCount(); ++i) {
+	    if (menu.getMenu(i) != null && tr("Edit").equals(menu.getMenu(i).getName())) {
+		edit = menu.getMenu(i);
+		break;
+	    }
+	}
+	if (edit == null) {
+	    edit = new JMenu(tr("Edit"));
+	    menu.add(edit, 2);
+	    edit.setVisible(false);
+	}
+	edit.add(addGridMenu);
+	addGridMenu.setVisible(false);
+    }
+	@Override
+	public void mapFrameInitialized(MapFrame oldFrame, MapFrame newFrame) {
+		if (oldFrame != null && newFrame == null) {
+			// disable
+			addGridMenu.setVisible(false);
+			if (edit.getMenuComponentCount() == 1)
+				edit.setVisible(false);
+		} else if (oldFrame == null && newFrame != null) {
+			// enable
+			addGridMenu.setVisible(true);
+			if (edit.getMenuComponentCount() == 1)
+				edit.setVisible(true);
+		}
+	}
+
+}