MapCalibrationData.java

/*************************************************************************
* Copyright (c) 2015 Lemberg Solutions
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
*    http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
**************************************************************************/

package com.ls.widgets.map.utils;

import android.graphics.Point;
import android.location.Location;
import android.util.Pair;

public class MapCalibrationData 
{
	private Pair<Point, Location> topLeft;
	private Pair<Point, Location> bottomRight;
	
	private float widthInMeters;
	private float heightInMeters;
	
	private float results[];
	
	public MapCalibrationData(Pair<Point, Location> topLeft, Pair<Point, Location> bottomRight)
	{
		this.topLeft = topLeft;
		this.bottomRight = bottomRight;
		results = new float[3];
		
		recalculateDistanceInMeters();
	}

	
	/**
	 * @return returns width of the calibration rectangle in pixels
	 */
	public int widthInPixels()
	{
		return bottomRight.first.x - topLeft.first.x; 
	}
	
	
	/**
	 * @return returns height of the calibration rectangle in pixels
	 */	
	public int heightInPixels()
	{
		return bottomRight.first.y - topLeft.first.y; 
	}
	
	
	/**
	 * @return Returns width of the calibration rectangle in degrees;
	 */
	public double widthInDegrees()
	{
		return bottomRight.second.getLongitude() - topLeft.second.getLongitude();
	}
	
	/**
	 * @return Returns height of the calibration rectangle in degrees;
	 */
	public double heightInDegrees()
	{
		return topLeft.second.getLatitude() - bottomRight.second.getLatitude();
	}
	
	
	/**
	 * @return Returns width of the calibration rectangle in meters;
	 */
	public float getWidthInMeters()
	{
		return widthInMeters;
	}
	
	
	/** 
	 * @return Returns height of the calibration rectangle in meters;
	 */
	public float getHeightInMeters()
	{
		return heightInMeters;
	}
	
	
	/**
	 * Converts location to position on the map.
	 * @param location instance of android.location.Location object.
	 * @param position - out parameter. Can be null.
	 * @return returns the same object that was passed as position, or if it is null - returns new Point object.
	 */
	public Point translate(final Location location, /*out*/Point position)
	{
		double heightCoef = (topLeft.second.getLatitude() - location.getLatitude()) / heightInDegrees();
		double widthCoef = (location.getLongitude() - topLeft.second.getLongitude()) / widthInDegrees();
		
		if (position == null) {
			position = new Point();
		}
			
		position.x = (int) (widthInPixels() * widthCoef + topLeft.first.x);
		position.y = (int) (heightInPixels()* heightCoef + topLeft.first.y);
		
		return position;
	}
	
	
	/**
	 * Converts position on the map to location coordinates.
	 * @param point - position on the map in pixels. Instance of android.graphics.Point
	 * @param location - out parameter. Will contain latitude and longitude of point on the map.
	 */
	public void translate(Point point, Location location) 
	{	
		translate(point.x, point.y, location);
	}
	

	/**
	 * Converts position on the map to location coordinates.
	 * @param x - x coordinate in map coordinate system.
	 * @param y - y coordinate in map coordinate system.
	 * @param location - out parameter. Will contain latitude and longitude of point on the map.
	 */
	public void translate(int x, int y, Location location) 
	{
		double heightCoef = (float)(topLeft.first.y - y) / (float)heightInPixels();
		double widthCoef = (float)(x - topLeft.first.x) / (float)widthInPixels();
		
		location.setLatitude(heightInDegrees() * heightCoef + topLeft.second.getLatitude());
		location.setLongitude(widthInDegrees() * widthCoef + topLeft.second.getLongitude());
	}
	
	
	
	private void recalculateDistanceInMeters() 
	{
		// width
		Location.distanceBetween(topLeft.second.getLatitude(), topLeft.second.getLongitude(), topLeft.second.getLatitude(), bottomRight.second.getLongitude(), results);
		widthInMeters = results[0];
		
		// height
		Location.distanceBetween(bottomRight.second.getLatitude(), topLeft.second.getLongitude(), topLeft.second.getLatitude(), topLeft.second.getLongitude(), results);
		heightInMeters = results[0];
	}

}