geoexplorer.gui

Class CoordinateConverter

java.lang.Object

geoexplorer.gui.CoordinateConverter

public class CoordinateConverter
extends java.lang.Object

A converter from map coordinates to screen coordinates. The maps coordinates are real values, whereas the screen coordinates are integer values (pixels). By default, the y axis is oriented from bottom to top for the map coordinate, the other way around for the screen coordinates. The top left pixel of the screen has coordinates (0, 0).

Version:

1.0

Author:

Sylvain B.

Constructor Summary

Constructors

Constructor and Description
CoordinateConverter(int screenWidth, int screenHeight, double centerX, double centerY, double mapWidth) The default constructor of the coordinate convertor.

Method Summary

Methods

Modifier and Type	Method and Description
double	dxScreenToMap(int dx) Converts an x distance from the screen reference to the map reference (the only difference with xScreenToMap is that it does not take into account the origin of the map reference.
double	dyScreenToMap(int dy) Converts a y distance from the screen reference to the map reference (the only difference with yScreenToMap is that it does not take into account the origin of the map reference.
int	xMapToScreen(double x) Converts an x coordinate from the map reference to the screen reference
double	xScreenToMap(int x) Converts an x coordinate from the screen reference to the map reference
int	yMapToScreen(double y) Converts a y coordinate from the map reference to the screen reference
double	yScreenToMap(int y) Converts a y coordinate from the screen reference to the map reference

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

CoordinateConverter

public CoordinateConverter(int screenWidth,
                   int screenHeight,
                   double centerX,
                   double centerY,
                   double mapWidth)

The default constructor of the coordinate convertor.

Parameters:

screenWidth - the screen width

screenHeight - the screen height

centerX - the x coordinate of the map center.

centerY - the y coordinate of the map center.

mapWidth - the map width (the map height is fixed to mapWidth × screenHeight / screenWidth, provided that we do not want the map to be deformed by the transformation).

Method Detail

xMapToScreen

public int xMapToScreen(double x)

Converts an x coordinate from the map reference to the screen reference

Parameters:

x - the x coordinate in the map reference to convert.

Returns:

the coordinate converted to the screen reference.

yMapToScreen

public int yMapToScreen(double y)

Converts a y coordinate from the map reference to the screen reference

Parameters:

y - the y coordinate in the map reference to convert.

Returns:

the coordinate converted to the screen reference.

xScreenToMap

public double xScreenToMap(int x)

Converts an x coordinate from the screen reference to the map reference

Parameters:

x - the x coordinate in the screen reference to convert.

Returns:

the coordinate converted to the map reference.

yScreenToMap

public double yScreenToMap(int y)

Converts a y coordinate from the screen reference to the map reference

Parameters:

y - the y coordinate in the screen reference to convert.

Returns:

the coordinate converted to the map reference.

dxScreenToMap

public double dxScreenToMap(int dx)

Converts an x distance from the screen reference to the map reference (the only difference with xScreenToMap is that it does not take into account the origin of the map reference.

Parameters:

dx - the distance to convert (in the screen reference)

Returns:

the distance converted to the map reference.

dyScreenToMap

public double dyScreenToMap(int dy)

Converts a y distance from the screen reference to the map reference (the only difference with yScreenToMap is that it does not take into account the origin of the map reference.

Parameters:

dy - the distance to convert (in the screen reference)

Returns:

the distance converted to the map reference.