dtedframe.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.

        // start in lower left of subframe
        double start_lat_index = (lat_origin - (double) dsi.sw_lat) * 36000.0
                / (double) uhl.lat_post_interval;
        double start_lon_index = (lon_origin - (double) dsi.sw_lon) * 36000.0
                / (double) uhl.lon_post_interval;
        double end_lat_index = ((lat_origin - ((double) dfsi.height * dfsi.yPixInterval)) - (double) dsi.sw_lat)
                * 36000.0 / (double) uhl.lat_post_interval;
        double end_lon_index = ((lon_origin + ((double) dfsi.width * dfsi.xPixInterval)) - (double) dsi.sw_lon)
                * 36000.0 / (double) uhl.lon_post_interval;
        double lat_interval = (start_lat_index - end_lat_index)
                / (double) dfsi.height;
        double lon_interval = (end_lon_index - start_lon_index)
                / (double) dfsi.width;

        if (Debug.debugging("dteddetail"))
            Debug.output("  start_lat_index => " + start_lat_index + "\n"
                    + "  end_lat_index => " + end_lat_index + "\n"
                    + "  start_lon_index => " + start_lon_index + "\n"
                    + "  end_lon_index => " + end_lon_index + "\n"
                    + "  lat_interval => " + lat_interval + "\n"
                    + "  lon_interval => " + lon_interval);

        short e1, e2;
        short xc = 0;
        short yc = 0;
        short xnw = 0;
        short ynw = 0;
        short xse = 0;
        short yse = 0;
        double slope;
        double distance = 1.0;
        float value = 0.0f;
        int assignment = 0;
        double modifier = (double) 0;
        double xw_offset = 0;
        double xe_offset = 0;
        double yn_offset = 0;
        double ys_offset = 0;
        int elevation = (int) 0;

        //  Calculations needed once for slope shading
        if (dfsi.viewType == DTEDFrameSubframe.SLOPESHADING
                || (dfsi.viewType == DTEDFrameSubframe.COLOREDSHADING && colortable.colors.length > DTEDFrameColorTable.NUM_ELEVATION_COLORS)) {
            // to get to the right part of the frame, kind of like a
            // subframe
            // indexing thing
            xw_offset = start_lon_index - Math.ceil(lon_interval);
            xe_offset = start_lon_index + Math.ceil(lon_interval);
            yn_offset = start_lat_index + Math.ceil(lat_interval);
            ys_offset = start_lat_index - Math.ceil(lat_interval);

            switch (dfsi.dtedLevel) {
            //larger numbers make less contrast
            case 0:
                modifier = (double) 4;
                break;//1000 ideal
            case 1:
                modifier = (double) .02;
                break;//2 ideal
            case 2:
                modifier = (double) .0001;
                break;
            case 3:
                modifier = (double) .000001;
                break;
            default:
                modifier = (double) 1;
            }
            // With more colors, contrast tends to be a little light
            // for the
            // default - brighten it up more
            if (colortable.colors.length > 215)
                modifier = modifier / 10;

            for (int h = dfsi.slopeAdjust; h < 5; h++)
                modifier = modifier * 10;
            distance = Math.sqrt((modifier * lon_interval * lon_interval)
                    + (modifier * lat_interval * lat_interval));
        }
        for (short x = 0; x < dfsi.width; x++) {

            //used for both elevation banding and slope
            xc = (short) (start_lon_index + ((x) * lon_interval));
            if (xc < 0)
                xc = 0;
            if (xc > dsi.num_lon_points - 1)
                xc = (short) (dsi.num_lon_points - 1);

            if ((elevations[xc] == null) && !read_data_record(xc)) {
                Debug.error("DTEDFrame: Problem reading lat point line in data record");
                return null;
            }
            if (dfsi.viewType == DTEDFrameSubframe.SLOPESHADING
                    || (dfsi.viewType == DTEDFrameSubframe.COLOREDSHADING && colortable.colors.length > DTEDFrameColorTable.NUM_ELEVATION_COLORS)) {
                //  This is actually finding the right x post for this
                // pixel,
                //  within the subframe measurements.
                xnw = (short) (xw_offset + Math.floor(x * lon_interval));
                xse = (short) (xe_offset + Math.floor(x * lon_interval));

                // trying to smooth out the edge of the frame
                if (xc == 0 || xnw < 0) {
                    xnw = xc;
                    xse = (short) (xnw + 2.0 * Math.ceil(lon_interval));
                }
                if (xc == dsi.num_lon_points - 1
                        || xse > dsi.num_lon_points - 1) {
                    xse = (short) (dsi.num_lon_points - 1);
                    xnw = (short) (xse - 2.0 * Math.ceil(lon_interval));
                }

                if (((elevations[xnw] == null) && !read_data_record(xnw))
                        || ((elevations[xse] == null) && !read_data_record(xse))) {
                    Debug.error("DTEDFrame: Problem reading lat point line in data record");
                    return null;
                }
            }

            // Now, calculate the data and assign the pixels based on
            // y
            for (short y = 0; y < dfsi.height; y++) {

                // used for elevation band and slope
                yc = (short) (start_lat_index - ((y) * lat_interval));
                if (yc < 0)
                    yc = 0;
                elevation = (int) elevations[xc][yc];

                // elevation shading
                if (dfsi.viewType == DTEDFrameSubframe.METERSHADING
                        || dfsi.viewType == DTEDFrameSubframe.FEETSHADING) {

                    // Just use the top two-thirds of the colors
                    if (elevation == 0)
                        assignment = 0; // color water Blue
                    else {
                        if (elevation < 0)
                            elevation *= -1; // Death Valley
                        if (dfsi.viewType == DTEDFrameSubframe.FEETSHADING)
                            elevation = (int) (elevation * 3.2);
                        // Start at the darkest color, and then go up
                        // through the
                        // colormap for each band height, the start
                        // back at the
                        // darkest when you get to the last color. To
                        // make this
                        // more useful, I limit the number of colors
                        // (10) used - if
                        // there isn;t enough contrast between the
                        // colors, you can't
                        // see the bands. The contrast adjustment in
                        // 24-bit color
                        // mode(216 colors) lets you add a few colors.
                        if (colortable.colors.length < 216) {
                            try {
                                assignment = (int) ((elevation / dfsi.bandHeight)
                                        % (colortable.colors.length - 6) + 6);
                            } catch (java.lang.ArithmeticException ae) {
                                assignment = 1;
                            }
                        } else {
                            try {
                                assignment = (int) (((elevation / dfsi.bandHeight)
                                        % (10 - 2 * (3 - dfsi.slopeAdjust)) * (colortable.colors.length / (10 - 2 * (3 - dfsi.slopeAdjust)))) + 6);
                            } catch (java.lang.ArithmeticException ae) {
                                assignment = 1;
                            }
                        }
                    }
                    if (dfsi.colorModel == OMRasterObject.COLORMODEL_DIRECT)
                        raster.setPixel(x,
                                y,
                                colortable.colors[assignment].getRGB());
                    else
                        raster.setByte(x, y, (byte) assignment);
                }

                // Slope shading
                else if (dfsi.viewType == DTEDFrameSubframe.SLOPESHADING
                        || (dfsi.viewType == DTEDFrameSubframe.COLOREDSHADING && colortable.colors.length > DTEDFrameColorTable.NUM_ELEVATION_COLORS)) {

                    // find the y post indexes within the subframe
                    ynw = (short) (yn_offset - Math.floor(y * lat_interval));
                    yse = (short) (ys_offset - Math.floor(y * lat_interval));

                    //  trying to smooth out the edge of the frame by
                    // handling the
                    //  frame limits
                    if (yse < 0)
                        yse = 0;
                    if (yc == dsi.num_lat_lines - 1
                            || ynw > dsi.num_lat_lines - 1)
                        ynw = (short) (dsi.num_lat_lines - 1);

                    e2 = elevations[xse][yse]; // down & right
                                               // elevation
                    e1 = elevations[xnw][ynw]; // up and left
                                               // elevation

                    slope = (e2 - e1) / distance; // slope relative to
                                                  // nw sun
                    // colormap value darker for negative slopes,
                    // brighter for
                    // positive slopes

                    if (dfsi.viewType == DTEDFrameSubframe.COLOREDSHADING) {
                        assignment = 1;
                        elevation = (int) (elevation * 3.2);// feet
                        for (int l = 1; l < DTEDFrameColorTable.NUM_ELEVATION_COLORS; l++)
                            if (elevation <= colortable.elevation_color_cutoff[l]) {
                                if (slope < 0)
                                    assignment = (int) (l + DTEDFrameColorTable.NUM_ELEVATION_COLORS);
                                else if (slope > 0)
                                    assignment = (int) (l + (DTEDFrameColorTable.NUM_ELEVATION_COLORS * 2));
                                else
                                    assignment = (int) l;
                                break;
                            }
                        if (elevation == 0)
                            assignment = 0;
                        if (dfsi.colorModel == OMRasterObject.COLORMODEL_DIRECT)
                            raster.setPixel(x,
                                    y,
                                    colortable.colors[assignment].getRGB());
                        else
                            raster.setByte(x, y, (byte) assignment);
                    }

                    else {
                        value = (float) (((colortable.colors.length - 1) / 2) + slope);

                        // not water, but close in the colormap - max
                        // dark
                        if (slope != 0 && value < 1)
                            value = 1;
                        if (elevation == 0)
                            value = 0; // water?!?
                        if (value > (colortable.colors.length - 1))
                            value = colortable.colors.length - 1; // max
                                                                  // bright

                        assignment = (int) value;
                        if (dfsi.colorModel == OMRasterObject.COLORMODEL_DIRECT)
                            raster.setPixel(x,
                                    y,
                                    colortable.colors[assignment].getRGB());
                        else
                            raster.setByte(x, y, (byte) assignment);

                    }
                }
                // Subframe outlines - different colors for each side
                // of the frame
                // This is really for debugging purposes, really.
                else if (dfsi.viewType == DTEDFrameSubframe.BOUNDARYSHADING) {
                    int c;
                    if (x < 1)
                        c = 1;
                    else if (x > dfsi.width - 2)
                        c = 12;
                    else if (y < 1)
                        c = 1;
                    else if (y > dfsi.height - 2)
                        c = 12;
                    else
                        c = 7;

                    if (dfsi.colorModel == OMRasterObject.COLORMODEL_DIRECT)
                        raster.setPixel(x, y, colortable.colors[c].getRGB());
                    else
                        raster.setByte(x, y, (byte) c);

                } else if (dfsi.viewType == DTEDFrameSubframe.COLOREDSHADING) {
                    assignment = 1;
                    elevation = (int) (elevation * 3.2);// feet
                    for (int l = 1; l < DTEDFrameColorTable.NUM_ELEVATION_COLORS; l++)
                        if (elevation <= colortable.elevation_color_cutoff[l]) {
                            assignment = (int) l;
                            break;
                        }

                    if (elevation == 0)
                        assignment = 0;
                    if (elevation < 0)
                        assignment = 1;
                    if (elevation > 33000)
                        assignment = 1;

                    if (dfsi.colorModel == OMRasterObject.COLORMODEL_DIRECT)
                        raster.setPixel(x,
                                y,
                                colortable.colors[assignment].getRGB());
                    else
                        raster.setByte(x, y, (byte) assignment);
                }
            }
        }

        if (Debug.debugging("dteddetail"))
            Debug.output("DTEDFrame: leaving raster");
        return raster;

    }

    public static void main(String args[]) {
        Debug.init();
        if (args.length < 1) {
            System.out.println("DTEDFrame:  Need a path/filename");
            System.exit(0);
        }

        System.out.println("DTEDFrame: " + args[0]);
        DTEDFrame df = new DTEDFrame(args[0]);
        if (df.frame_is_valid) {
            System.out.println(df.uhl);
            System.out.println(df.dsi);

            //          int startx = 5;
            //          int starty = 6;
            //          int endx = 10;
            //          int endy = 30;

            //          short[][] e = df.getElevations(startx, starty, endx,
            // endy);
            //          for (int i = e[0].length-1; i >= 0; i--) {
            //              for (int j = 0; j < e.length; j++) {
            //                  System.out.print(e[j][i] + " ");
            //              }
            //              System.out.println("");
            //          }
        }
        float lat = df.dsi.lat_origin + .5f;
        float lon = df.dsi.lon_origin + .5f;

        CADRG crg = new CADRG(new com.bbn.openmap.LatLonPoint(lat, lon), 1500000, 600, 600);
        final OMRaster ras = df.getOMRaster(crg);

        // Pushes the image to the left top of the frame.
        crg.setHeight(ras.getHeight());
        crg.setWidth(ras.getWidth());

        ras.generate(crg);

        java.awt.Frame window = new java.awt.Frame(args[0]) {
            public void paint(java.awt.Graphics g) {
                if (ras != null) {
                    ras.render(g);
                }
            }
        };

        window.addWindowListener(new java.awt.event.WindowAdapter() {
            public void windowClosing(java.awt.event.WindowEvent e) {
                // need a shutdown event to notify other gui beans and
                // then exit.
                System.exit(0);
            }
        });

        window.setSize(ras.getWidth(), ras.getHeight());
        window.show();
        window.repaint();
    }
}