projection.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.

// **********************************************************************
// 
// <copyright>
// 
//  BBN Technologies
//  10 Moulton Street
//  Cambridge, MA 02138
//  [phone]
// 
//  Copyright (C) BBNT Solutions LLC. All rights reserved.
// 
// </copyright>
// **********************************************************************
// 
// $Source: /cvs/distapps/openmap/src/openmap/com/bbn/openmap/proj/Projection.java,v $
// $RCSfile: Projection.java,v $
// $Revision: 1.4.2.1 $
// $Date: 2004/10/14 18:27:38 $
// $Author: dietrick $
// 
// **********************************************************************

package com.bbn.openmap.proj;

import java.awt.Point;
import java.awt.Image;
import java.util.ArrayList;

import com.bbn.openmap.LatLonPoint;

/**
 * Projection interface to the OpenMap projection library.
 * <p>
 * This is a READONLY interface to the projection object. See the
 * <code>Proj</code> class for read/write access.
 * <p>
 * A projection is an object that is maintained by the map, and
 * represents a abstract "view" of the data. The projection has the
 * properties of x-width, * y-height, scale (in pixels/meters), and
 * latitude/longitude center point.
 * <p>
 * 
 * <h4>Projection Notes/Assumptions:</h4>
 * <ul>
 * <li>At the center point of the projection, North is to the top of
 * the screen. <br>
 * <li><a href="#poly_restrictions">LatLon Polygon Restrictions. </a>
 * <br>
 * <li><a href="#line_restrictions">LatLon Line Restrictions. </a>
 * <br>
 * </ul>
 * <p>
 * 
 * <h4>Implementation Notes:</h4>
 * <ul>
 * <li>This methods in this interface are safe to use among different
 * threads, BUT the underlying classes may not be. Use with care.
 * </ul>
 * <p>
 * 
 * <h4>Bibliography:</h4>
 * <br>
 * Many of the specific projection equations were taken from <i>Map
 * Projections --A Working Manual </i>, by John Synder.
 * <p>
 * 
 * @see Proj
 * @see Cylindrical
 * @see Mercator
 * @see CADRG
 * @see Azimuth
 * @see Orthographic
 *  
 */
public interface Projection extends java.io.Serializable {

    /**
     * Get the scale.
     * 
     * @return float scale
     */
    public float getScale();

    /**
     * Get the maximum scale.
     * 
     * @return float maxscale
     */
    public float getMaxScale();

    /**
     * Get the minimum scale.
     * 
     * @return float minscale
     */
    public float getMinScale();

    /**
     * Get the center LatLonPoint.
     * 
     * @return center point
     */
    public LatLonPoint getCenter();

    /**
     * Get the width of the map.
     * 
     * @return int width.
     */
    public int getWidth();

    /**
     * Get the height of the map.
     * 
     * @return int height.
     */
    public int getHeight();

    /**
     * Get the type of projection.
     * 
     * @return int type
     */
    public int getProjectionType();

    /**
     * Get the projection ID string.
     * 
     * @return String projID
     */
    public String getProjectionID();

    /**
     * Get the upper left (northwest) point of the projection.
     * <p>
     * Returns the upper left point (or closest equivalent) of the
     * projection based on the center point and height and width of
     * screen.
     * <p>
     * This is trivial for most cylindrical projections, but much more
     * complicated for azimuthal projections.
     * 
     * @return LatLonPoint
     */
    public LatLonPoint getUpperLeft();

    /**
     * Get the lower right (southeast) point of the projection.
     * <p>
     * Returns the lower right point (or closest equivalent) of the
     * projection based on the center point and height and width of
     * screen.
     * <p>
     * This is trivial for most cylindrical projections, but much more
     * complicated for azimuthal projections.
     * 
     * @return LatLonPoint
     */
    public LatLonPoint getLowerRight();

    /**
     * Checks if a LatLonPoint is plot-able.
     * <p>
     * Call this to check and see if a LatLonPoint can be plotted.
     * This is meant to be used for checking before projecting and
     * rendering Point objects (bitmaps or text objects tacked at a
     * LatLonPoint for instance).
     * 
     * @param llpoint LatLonPoint
     * @return boolean
     */
    public boolean isPlotable(LatLonPoint llpoint);

    /**
     * Checks if a LatLonPoint is plot-able.
     * <p>
     * Call this to check and see if a LatLonPoint can be plotted.
     * This is meant to be used for checking before projecting and
     * rendering Point objects (bitmaps or text objects tacked at a
     * LatLonPoint for instance).
     * 
     * @param lat float latitude in decimal degrees
     * @param lon float longitude in decimal degrees
     * @return boolean
     */
    public boolean isPlotable(float lat, float lon);

    /**
     * Forward project a LatLonPoint into XY space.
     * 
     * @param llpoint LatLonPoint
     * @return Point (new)
     */
    public Point forward(LatLonPoint llpoint);

    /**
     * Forward projects a LatLonPoint into XY space and return a
     * Point.
     * 
     * @param llp LatLonPoint to be projected
     * @param pt Resulting XY Point
     * @return Point pt
     */
    public Point forward(LatLonPoint llp, Point pt);

    /**
     * Forward project lat,lon coordinates into xy space.
     * 
     * @param lat float latitude in decimal degrees
     * @param lon float longitude in decimal degrees decimal degrees
     * @return Point (new)
     */
    public Point forward(float lat, float lon);

    /**
     * Forward projects lat,lon coordinates into XY space and returns
     * a Point.
     * 
     * @param lat float latitude in decimal degrees
     * @param lon float longitude in decimal degrees
     * @param pt Resulting XY Point
     * @return Point pt
     */
    public Point forward(float lat, float lon, Point pt);

    /**
     * Forward projects lat,lon coordinates into XY space and returns
     * a Point.
     * 
     * @param lat float latitude in radians
     * @param lon float longitude in radians
     * @param pt Resulting XY Point
     * @param isRadian placeholder argument indicating that lat,lon
     *        arguments are in radians (can be true or false)
     * @see #forward(float,float,Point)
     * @return Point pt
     */
    public Point forward(float lat, float lon, Point pt, boolean isRadian);

    /**
     * Inverse project a Point.
     * 
     * @param point XY Point
     * @return LatLonPoint (new)
     */
    public LatLonPoint inverse(Point point);

    /**
     * Inverse project a point with llpt.
     * 
     * @param point x,y Point
     * @param llpt resulting LatLonPoint
     * @return LatLonPoint llpt
     */
    public LatLonPoint inverse(Point point, LatLonPoint llpt);

    /**
     * Inverse project x,y coordinates.
     * 
     * @param x
     * @param y
     * @return LatLonPoint (new)
     */
    public LatLonPoint inverse(int x, int y);

    /**
     * Inverse project x,y coordinates into a LatLonPoint.
     * 
     * @param x integer x coordinate
     * @param y integer y coordinate
     * @param llpt LatLonPoint
     * @return LatLonPoint llpt
     * @see Proj#inverse(Point)
     */
    public LatLonPoint inverse(int x, int y, LatLonPoint llpt);

    /**
     * Pan the map/projection.
     * <ul>
     * <li><code>pan(