Creating vector class

public class Vec2D I

public float dx, dy;

public void setVec (float dx, float dy) I

this.dx = dx;

this.dy = dy;

public float mag () {

return (float) Math.sgrt(dx * dx + dy * dy);

public void addVec (Vec2D vec) I

dx += vec.dx;

dy += vec.dy;

public void subVec (Vec2D vec) I

dx -= vec.dx:

dy -= vec.dy;

public void unitVec () f

float mag = mag();

setVec(dx / mag, dy / mag);

public void mulVec (float scale) t

setVec(dx * scale, dy * scale);

paddle

class Paddle I

public int x, y, width, height;

private Color color;

Paddle (int x, int y, int width, int height,

Color color) I

th'is.x = x:

this.y = y;

this.width = width;

this.height = height;

this.color = color;

public void move (int x, Rectangle bd) I

i f ( x > (width >> 1) && x < (bd.width - (width )> l)))

this.x = x;

public int checkReturn (Ball ball, boolean plyr,

i nt rl, int r2, int r3) I

if (plyr && ball.y > (y - ball.radius)

! plyr && ball.y < (y + ball.radius))

if ((int) Math.abs(ball.x - x) < (width 1 2 +

ball.radius)) I

ball.dy = -ball.dy;

1! Put a little english on the ball

ball.dx += (int) (ball.dx * Math.abs(ball.x - x) /

(width / 2));

return r2;

else

return r3;

return rl;

public void draw (Graphics g) f

g.setColor(color);

g.fillRect(x - (width >> 1), y, width, height);

ball bounce

public void move (Rectangle bounds) I

// Add velocity values dx/dy to position to

get ,

// ball s new position

x +_ dx;

y +° dy;

// Check for collision with left edge

if (x < bounds.x && dx < 0)

dx = -dx;

x -= 2 * (x - bounds.x);

// Check for collision with right edge

else if ((x + size) ) (bounds.x + bounds.width) &&

d x > 0' )

dx = -dx;

x -= 2 * ((x + size) - (bounds.x + bounds.width));

// Check for collision with top edge

if (y < bounds.y && dy < 0) I

dy = -dy;

y -° 2 * (y - bounds.y);

// Check for collision with bottom edge

else i f (( y + size) > ( bounds.y + bounds.height) &&

dy = -dy;

y -= 2 * ((y + size) - (bounds.y + bounds.height));

moving the ball