Vec2.java

package com.android.droidgraph.util;

import android.util.Log;

public class Vec2 
{
        /**
         * x coordinate of the vector
         */
        private double x;
        
        /**
         * y coordinate of the vector
         */
        private double y;
        
        /**
         * Empty constructor, initializes to 0
         */
        public Vec2()
        {
                this.x = 0;
                this.y = 0;
        }
        
        /**
         * Creates an instance of the Vec2 class and initializes x and y
         * @param x
         * @param y
         */
        public Vec2(double x, double y)
        {
                this.x = x;
                this.y = y;
        }

        /**
         * Calculates if this Vec2 is equal to the one provided
         * @param v is the Vec2 to compare against
         * @return True if it's equal, false if it isn't
         */
        public boolean Equals(Vec2 v)
        {
                if(this.x == v.x && this.y == v.y) return true;
                else return false;
        }
        
        /**
         * Calculates the vector length
         * @return the length of the vector
         */
        public double Length()
        {
                return Math.sqrt((this.x*this.x + this.y*this.y));
        }
        
        /**
         * Normalizes the vector
         */
        public void Normalize()
        {
                double len = Length();
                this.x /= len;
                this.y /= len;
        }
        
        /**
         * Returns a vector from this to the point provided
         * @param point to calculate the vector to
         * @return The vector.
         */
        public Vec2 GetVectorTo(Vec2 point)
        {
                Vec2 aux = new Vec2();
                
                aux.SetX(point.x - this.x);
                aux.SetY(point.y - this.y);
                
                return aux;
        }
        
        public Vec2 GetVectorTo(int x, int y)
        {
                Vec2 aux = new Vec2();
                
                aux.SetX(x - this.x);
                aux.SetY(y - this.y);
                
                return aux;
        }
        
        /**
         * Sets the x,y
         * @param x
         * @param y
         */
        public void Set(double x, double y)
        {
                this.x = x;
                this.y = y;
        }
        
        /**
         * Sets the x
         * @param x
         */
        public void SetX(double x)
        {
                this.x = x;
        }
        
        /**
         * Sets the y
         * @param y
         */
        public void SetY(double y)
        {
                this.y = y;
        }
        
        /**
         * Adds the offset to the current position
         * @param x to add to the x component
         * @param y to add to the y component
         */
        public void Offset(double x, double y)
        {
                this.x += x;
                this.y += y;
        }
        
        /**
         * Gets the x value
         * @return x
         */
        public double X() { return this.x; }
        
        /**
         * Gets the y value
         * @return y
         */
        public double Y() { return this.y; }
        
        /**
         * Prints the vector value to the log
         */
        public void Print(String tag, String msg)
        {
                Log.i(tag, msg + ": " + this.x + ", " + this.y);
        }
        
        /**
         * Calculates the dot product of this Vec2 with another
         * @param vec Vec2 to do the product with
         * @return the dot product
         */
        public float Dot(Vec2 vec)
        {
                return (float) (this.x * vec.X() + this.y * vec.Y());
        }
        
        /**
         * Adds to this Vec2 the values of another
         * @param vec Vec2 to add
         */
        public void Add(Vec2 vec)
        {
                this.x += vec.X();
                this.y += vec.Y();
        }
        
        /**
         * Multiplies the x and y components by the value
         * @param val Multiplier for the components
         */
        public void Scale(float val)
        {
                this.x *= val;
                this.y *= val;
        }
        
        /**
         * Gets a Vec2 with the truncated values of the float coordinates
         * @return A Vec2 with no decimals.
         */
        public Vec2 GetIntValue()
        {
                Vec2 intVec = new Vec2();
                intVec.Set((int)this.x, (int)this.y);
                return intVec;
        }
        
        /**
         * Checks if the rounded coordinates of both vectors are equal
         * @param vec Vec2 to check against
         * @return True if they are equal, false if they are not.
         */
        public boolean RoundEqual(Vec2 vec)
        {
                return ( (Math.round(this.x) == Math.round(vec.X())) && (Math.round(this.y) == Math.round(vec.Y())));
        }

}