/**********************************************************
 Main Class File: PointMaker.java
 This file:       Point.java

 Author: CS302 Section 5
 Date:   9-24-03
**********************************************************/

/**
 * The Point class is a wrapper for (x,y) coordinates.
 */
class Point {

	private int x;		// x-coordinate
	private int y;		// y-coordinate

	/**
	 * The constructor sets initial values for (x,y).
	 * 	@param xVal The value of the x-coordinate.
	 *	@param yVal The value of the y-coordinate.
	 */
	public Point(int xVal, int yVal) {

		x = xVal;
		y = yVal;
	}

	/**
	 * Accessor for the x-coordinate.
	 *	@return The x-coordinate.
	 */
	public int getX() {

		return x;
	}

	/**
	 * Accessor for the y-coordinate.
	 *	@return The y-coordinate.
	 */
	public int getY() {

		return y;
	}

	/**
	 * Switches the x and y coordinates.
	 */
	public void invert() {

		int temp = x;
		x = y;
		y = temp;
	}

	

	/**
	 * Adds another Point to this one.
	 *	@param p The other Point.
	 */
	public void add(Point p) {

		x = x + p.x;
		y = y + p.y;
	}



	/**
	 * Computes distance from another Point to this one.
	 *	@param p The other Point.
	 */
	public double getDistanceFrom(Point p) {

		int dx = x – p.x;	// distance along x-axis
		int dy = y – p.y;	// distance along y-axis

		// This is the distance formula. We are casting 
		// (dx*dx + dy*dy) into a double because the sqrt
		// method requires a parameter of type double.
		// Since sqrt returns a double, the return type
		// of this whole method is also double.
		return Math.sqrt( (double) dx*dx + dy*dy);
	}



	/**
	 * Returns a new Point, the inverse of this one.
	 *	@return The inverse Point.
	 */
	public Point getInvert() {

		Point invert = new Point(y,x);
		return invert;
	}



	/**
	 * Returns a new Point, halfway between another
	 * Point and this one.
	 *	@param p The other point.
	 *	@return The halfway Point.
	 */
	public Point getHalfwayPoint() {

		int newX = (x + p.x) / 2;
		int newY = (y + p.y) / 2;
		return new Point(newX, newY);
	}

}