Bird.java

import greenfoot.*;  // (World, Actor, GreenfootImage, Greenfoot and MouseInfo)

/**
 * Write a description of class bird1 here.
 *
 * @author (your name)
 * @version (a version number or a date)
 */
public class Bird extends SharedResources
{
    protected  int BirdX = 80;
    protected  int BirdY = 200;

    int velocity2 = 0;
    private static final double boostSpeed = -6;

    GreenfootImage bird_image_1 = new GreenfootImage("flappybird1.png");
    GreenfootImage bird_image_2 = new GreenfootImage("flappybird2.png");
    GreenfootImage bird_image_3 = new GreenfootImage("flappybird3.png");

    static final private double Gravity = .5;
    private double velocity = 0;

    /**
     * Act - do whatever the bird1 wants to do. This method is called whenever
     * the 'Act' or 'Run' button gets pressed in the environment.
     */
    public void act()
    {
        // Add your action code here.
        apllyGravity();
        checkKeys();
        rotateBird();
        checkCollisions();
    }

    public void apllyGravity()
    {
        addBirdY((int)velocity);
        velocity +=Gravity;
        animateBird();
        setLocation(getBirdX(),getBirdY());
    }

    public void checkKeys()
    {
        if(Greenfoot.isKeyDown("space") || Greenfoot.mouseClicked(null))
        {
            velocity = boostSpeed;
        }
    }

    public void rotateBird()
    {
        if(velocity < 1) {
            setRotation(-30);
        } else if(velocity < 8) {
            setRotation(0);
        } else if(velocity < 12) {
            setRotation(30);
        } else if(velocity < 90) {
            setRotation(90);
        }
    }

    public void animateBird()
    {
        frame++;

        if(frame < 1 * animationDelay) {
            setImage(bird_image_1);
        }
        else if(frame < 2 * animationDelay) {
            setImage(bird_image_2);
        }
        else if(frame < 3 * animationDelay) {
            setImage(bird_image_3);
            frame = 0;
        }
    }

    public void checkCollisions() {
        Actor ground = getOneIntersectingObject(Ground.class);
        Actor Pipe = getOneIntersectingObject(Pipe.class);
        if(ground != null || Pipe != null) {
            setLocation(getX(), 322);
            Greenfoot.stop();
        }
    }

    protected int getBirdX() {
        return BirdX;
    }

    protected int getBirdY() {
        return BirdY;
    }

    protected void addBirdY(double x) {
        BirdY += (int)x;
    }
}