[Game AI][Steering Behavior] Task_Wall Avoidance (engine.Vector)

engine에 새로 만들어야한다.

package engine;

/**
 * This comes directly from http://introcs.cs.princeton.edu/java/34nbody/Vector.java.html
 * with a few changes
 * @author stephencalabro
 */

public class Vector {
	public double x;
	public double y;
	
	// create the zero vector of length N
	public Vector(double _x, double _y) {
	    x = _x;
	    y = _y;
	}
	
	// return the inner product of this Vector a and b
	public double dot(Vector that) {
	    double sum = 0.0;
	    
	    sum = sum + (this.x*that.x);
	    sum = sum + (this.y*that.y);
	    return sum;
	}
	
	// return the Euclidean norm of this Vector
	public double magnitude() {
	    return Math.sqrt(this.dot(this));
	}
	
	// return the Euclidean distance between this and that
	public double distanceTo(Vector that) {
	    return this.minus(that).magnitude();
	}
	
	// return this + that
	public Vector plus(Vector that) {
	    Vector c = new Vector(x, y);

	    c.x = this.x + that.x;
	    c.y = this.y + that.y;
	    return c;
	}
	
	// return this - that
	public Vector minus(Vector that) {
	    Vector c = new Vector(x, y);

	    c.x = this.x - that.x;
	    c.y = this.y - that.y;
	    return c;
	}
	
	/* Don't think I need this
	// return the corresponding coordinate
	public double cartesian(int i) {
	    return data[i];
	}
	*/
	
	// create and return a new object whose value is (this * factor)
	public Vector times(double factor) {	    
	    Vector c = new Vector(x, y);

	    c.x = factor * this.x;
	    c.y = factor * this.y;
	    return c;
	}
	
	
	// return the corresponding unit vector
	public Vector direction() {
	    if (this.magnitude() == 0.0) throw new RuntimeException("Zero-vector has no direction");
	    return this.times(1.0 / this.magnitude());
	}
	
	public Vector normalize() {
		Vector c = new Vector(x, y);

		c.x = this.x / this.magnitude();
		c.y = this.y / this.magnitude();
		
		return c;
	}
	
	public static Vector Normalize(Vector v) {
		Vector c = new Vector(v.x, v.y);

		c.x = v.x / v.magnitude();
		c.y = v.y / v.magnitude();
		
		return c;
	}
	
	// return a string representation of the vector
	public String toString() {
	    StringBuilder s = new StringBuilder();
	    s.append("(");
	    s.append(this.x);
	    s.append(", ");
	    s.append(this.y);
	    s.append(")");
	    return s.toString();
	}
}