utmgridplugin.java

openmap java写的开源数字地图程序. 用applet实现,可以像google map 那样放大缩小地图.

                poly = new PolylineGeometry.LL(vertPoints[i], OMGraphic.DECIMAL_DEGREES, OMGraphic.LINETYPE_GREATCIRCLE);
                polys.add(poly);
            }
            polys.setLinePaint(distanceGridPaint);
            list.add(polys);
        } else {

            // This doesn't seem to calculate the right
            // lines, although it looks like it should.

            if (UTM_DEBUG) {
                Debug.output("Doing vertical lines");
            }

            utm1.northing = startNorthing;
            utm2.northing = endNorthing;

            // Vertical lines
            for (i = 1; i <= 9; i++) {
                utm1.easting = i * 100000f;
                utm2.easting = i * 100000f;

                point1 = utm1.toLatLonPoint(Ellipsoid.WGS_84, point1);
                point2 = utm2.toLatLonPoint(Ellipsoid.WGS_84, point2);

                line = new OMLine(point1.getLatitude(), point1.getLongitude(), point2.getLatitude(), point2.getLongitude(), OMGraphic.LINETYPE_GREATCIRCLE);
                line.setLinePaint(distanceGridPaint);
                list.add(line);
            }
        }

        return list;
    }

    /**
     * Create a list of rectangles representing equal areas of MGRS
     * coordinates around a lat/lon location. The rectangles are laid
     * out on the MGRS grid, their size determined by the accuracy
     * limitation given, which reflects how many digits are provided
     * in a MGRS coordinate. Uses WGS 84 ellipsoid.
     * 
     * @param llp the lat/lon point of concern.
     * @param accuracy the number of digits for northing and easting
     *        values of a MGRS coordinate, which implicitly translates
     *        to meters - 5 (1 meter) to 1 (10,000 meter).
     * @param numRects the number of rectangles in each direction from
     *        the llp to create.
     */
    protected OMGeometryList createMGRSRectangles(LatLonPoint llp,
                                                  int accuracy, int numRects) {
        return createMGRSRectangles(llp, accuracy, numRects, Ellipsoid.WGS_84);
    }

    /**
     * Create a list of rectangles representing equal areas of MGRS
     * coordinates around a lat/lon location. The rectangles are laid
     * out on the MGRS grid, their size determined by the accuracy
     * limitation given, which reflects how many digits are provided
     * in a MGRS coordinate.
     * 
     * @param llp the lat/lon point of concern.
     * @param accuracy the number of digits for northing and easting
     *        values of a MGRS coordinate, which implicitly translates
     *        to meters - 5 (1 meter) to 1 (10,000 meter).
     * @param numRects the number of rectangles in each direction from
     *        the llp to create.
     * @param ellipsoid the ellipsoid to use.
     */
    protected OMGeometryList createMGRSRectangles(LatLonPoint llp,
                                                  int accuracy, int numRects,
                                                  Ellipsoid ellipsoid) {
        MGRSPoint mgrs = new MGRSPoint();
        mgrs.setAccuracy(accuracy);
        MGRSPoint.LLtoMGRS(llp, ellipsoid, mgrs);

        mgrs = new MGRSPoint(mgrs.getMGRS());
        mgrs.setAccuracy(accuracy);

        float accuracyBonus = 100000f / (float) Math.pow(10, accuracy);

        OMGeometryList list = new OMGeometryList();

        for (float i = -numRects * accuracyBonus; i < numRects * accuracyBonus; i += accuracyBonus) {
            for (float j = -numRects * accuracyBonus; j < numRects
                    * accuracyBonus; j += accuracyBonus) {
                if (Debug.debugging("utmdistancegrid")) {
                    System.out.print(".");
                }
                list.add(createMGRSRectangle(mgrs,
                        i,
                        j,
                        accuracyBonus,
                        ellipsoid));
            }
            if (Debug.debugging("utmdistancegrid")) {
                System.out.println("");
            }
        }

        return list;
    }

    /**
     * Create a polygon representing an equidistant area, at a meters
     * offset with a meters interval.
     * 
     * @param mgrsBasePoint the center point of interest that has been
     *        normalized for the units of the rectangle (meters, km,
     *        etc).
     * @param voffset vertical offset in meters, normalized for units,
     *        for entire polygon.
     * @param hoffset horizontal offset in meters, normalized for
     *        units, for entire polygon.
     * @param interval edge length of rectangle polygon in meters,
     *        normalized for units.
     * @param ellipsoid Ellipsoid for coordinate translation.
     */
    protected OMGeometry createMGRSRectangle(MGRSPoint mgrsBasePoint,
                                             float voffset, float hoffset,
                                             float interval, Ellipsoid ellipsoid) {

        float[] llpoints = new float[10];

        float easting = mgrsBasePoint.easting + hoffset;
        float northing = mgrsBasePoint.northing + voffset;
        int zone_number = mgrsBasePoint.zone_number;
        char zone_letter = mgrsBasePoint.zone_letter;

        LatLonPoint llp1 = new LatLonPoint();
        MGRSPoint.MGRStoLL(ellipsoid,
                northing,
                easting,
                zone_number,
                zone_letter,
                llp1);
        llpoints[0] = llp1.getLatitude();
        llpoints[1] = llp1.getLongitude();
        llpoints[8] = llp1.getLatitude();
        llpoints[9] = llp1.getLongitude();

        MGRSPoint.MGRStoLL(ellipsoid,
                northing,
                easting + interval,
                zone_number,
                zone_letter,
                llp1);
        llpoints[2] = llp1.getLatitude();
        llpoints[3] = llp1.getLongitude();

        MGRSPoint.MGRStoLL(ellipsoid,
                northing + interval,
                easting + interval,
                zone_number,
                zone_letter,
                llp1);
        llpoints[4] = llp1.getLatitude();
        llpoints[5] = llp1.getLongitude();

        MGRSPoint.MGRStoLL(ellipsoid,
                northing + interval,
                easting,
                zone_number,
                zone_letter,
                llp1);
        llpoints[6] = llp1.getLatitude();
        llpoints[7] = llp1.getLongitude();

        MGRSPoint mgrs = new MGRSPoint(northing, easting, zone_number, zone_letter);
        mgrs.setAccuracy(mgrsBasePoint.getAccuracy());
        MGRSPoint.MGRStoLL(mgrs, ellipsoid, llp1);
        String mgrsString = mgrs.getMGRS();

        if (Debug.debugging("utmgriddetail"))
            Debug.output(" - assigning " + mgrsString + " to poly with "
                    + mgrs.getAccuracy());

        PolygonGeometry poly = new PolygonGeometry.LL(llpoints, OMGraphic.DECIMAL_DEGREES, (interval <= 1000 ? OMGraphic.LINETYPE_STRAIGHT
                : OMGraphic.LINETYPE_GREATCIRCLE));
        poly.setAppObject(mgrsString);
        return poly;
    }

    /**
     * The getRectangle call is the main call into the PlugIn module.
     * The module is expected to fill the graphics list with objects
     * that are within the screen parameters passed.
     * 
     * @param p projection of the screen, holding scale, center
     *        coords, height, width.
     */
    public OMGraphicList getRectangle(Projection p) {

        OMGraphicList list = getList();

        if (verticalList == null) {
            verticalList = createUTMZoneVerticalLines();
            horizontalList = createUTMZoneHorizontalLines();
            labelTree = createUTMZoneLabels();
        }

        list.clear();

        if (showZones) {
            list.add(verticalList);
            list.add(horizontalList);
        }

        LatLonPoint center = p.getCenter();
        UTMPoint utm = new UTMPoint(center);

        if (show100kGrid) {
            Debug.message("utmgrid", "Creating 100k distance lines...");

            OMGraphicList hunKLines = createEquiDistanceLines(utm, 100000);
            list.add(hunKLines);
        }

        if (distanceGridResolution > 0) {
            Debug.message("utmgrid", "Creating distance lines...");

            float decisionAid = 100000f / (float) Math.pow(10,
                    distanceGridResolution);
            float dglc = 30f * decisionAid; // distance grid label
                                            // cutoff
            //          Debug.output("Basing decision to display labels on " +
            // dglc);

            int numberBasedForScale = (int) (p.getScale() / (2 * decisionAid));
            if (numberBasedForScale > 10) {
                numberBasedForScale = 10;
            }
            //          Debug.output(numberBasedForScale + "");

            OMGeometryList geoList = createMGRSRectangles(center,
                    distanceGridResolution,
                    numberBasedForScale);

            if (showLabels && p.getScale() <= dglc) {
                Debug.message("utmgrid",
                        "Creating labels for distance lines ...");

                OMGraphicList textList = new OMGraphicList();
                LatLonPoint llp = new LatLonPoint();
                Point point = new Point();
                Iterator it = geoList.iterator();
                while (it.hasNext()) {
                    PolygonGeometry.LL pll = (PolygonGeometry.LL) it.next();
                    String labelString = (String) (pll).getAppObject();
                    if (labelString == null) {
                        continue;
                    }
                    float[] ll = pll.getLatLonArray();
                    llp.setLatLon(ll[0], ll[1], true);

                    p.forward(llp, point);

                    double x = point.getX();
                    double y = point.getY();
                    int buffer = 20;

                    // Lame attempt of testing whether the label is
                    // on-screen
                    if ((x > -buffer || x < p.getWidth() + buffer)
                            && (y > -buffer || y < p.getHeight() + buffer)) {

                        OMText label = new OMText(llp.getLatitude(), llp.getLongitude(), 4, -4, labelString, OMText.JUSTIFY_LEFT);
                        label.setLinePaint(distanceGridPaint);
                        textList.add(label);
                    }
                }
                list.add(textList);
            }

            geoList.setLinePaint(distanceGridPaint);
            list.add(geoList);
        }

        if (labelList != null) {
            labelList.clear();
        } else {
            labelList = new OMGraphicList();
        }

        if (showLabels && p.getScale() <= labelCutoffScale) {
            Debug.message("utmgrid", "Creating labels for map...");
            LatLonPoint ul = p.getUpperLeft();
            LatLonPoint lr = p.getLowerRight();

            Vector labels = labelTree.get(ul.getLatitude(),
                    ul.getLongitude(),
                    lr.getLatitude(),
                    lr.getLongitude());

            labelList.setTargets(labels);
            labelList.setLinePaint(getUTMGridPaint());
            list.add(labelList);
        }

        Debug.message("utmgrid", "Generating OMGraphics...");
        list.generate(p);
        Debug.message("utmgrid", "Done.");
        return list;
    } //end getRectangle

    public Component getGUI() {
        JPanel panel = new JPanel();

        GridBagLayout gridbag = new GridBagLayout();
        GridBagConstraints c = new GridBagConstraints();
        panel.setLayout(gridbag);

        JCheckBox setZonesButton = new JCheckBox(i18n.get(UTMGridPlugIn.class,
                "setZonesButton",
                "Show UTM Zone Grid"), showZones);
        setZonesButton.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent ae) {
                JCheckBox button = (JCheckBox) ae.getSource();
                showZones = button.isSelected();
                doPrepare();
            }
        });
        c.gridy = 0;
        c.anchor = GridBagConstraints.WEST;
        gridbag.setConstraints(setZonesButton, c);
        panel.add(setZonesButton);

        JCheckBox set100kGridButton = new JCheckBox(i18n.get(UTMGridPlugIn.class,
                "set100kGridButton",
                "Show 100Km Distance Grid"), show100kGrid);
        set100kGridButton.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent ae) {
                JCheckBox button = (JCheckBox) ae.getSource();
                show100kGrid = button.isSelected();
                doPrepare();
            }
        });