Thread: Help with the body/tail of Snake

Hi, I'm trying to create a snake game, but I can't make the body/tail to follow correctly at the back of the snake's head.
Honestly, I don't know what to do here..


here's my code

import java.awt.*;
import javax.swing.*;
import java.awt.event.*;
import java.awt.event.ActionEvent;
import java.util.Random;
public class snake extends JPanel implements ActionListener,KeyListener{
		static JFrame frame = new  JFrame();
		static int x = 150,y=150,x1=x-10,y1=y,eposx=200,eposy=120,n=0;
		static int slength = 3;
		boolean right = true,left=true,up=true,down=true,rmove=true,lmove=false,umove=false,dmove=false;
		Timer tmr = new Timer(50,this);
		Random rdm = new Random();
 
	public snake(){
		setLayout(null);		
		this.requestFocus();
		addKeyListener(this);
        setFocusable(true);
        setFocusTraversalKeysEnabled(false);
	}
 
	public void actionPerformed(ActionEvent e){
	if(e.getSource()==tmr){
 
		if(right==true&&lmove==false){
		x=x+5;
 
		System.out.println("X = " + x + " Y = " + y);
		}
		if(left==true&&rmove==false){
		x=x-5;
 
			System.out.println("X = " + x + " Y = " + y);
		}
		if(up==true&&dmove==false){
		y=y-5;
 
		System.out.println("X = " + x + " Y = " + y);
 
		}
		if(down==true&&umove==false){
		y=y+5;
		System.out.println("X = " + x + " Y = " + y);
		}
	}
	if(x>=280){
		x=0;
 
	}
	else if(x<=00){
		x=280;
	}
	else if(y<=00){
		y=260;
 
	}
	else if(y>=260){
		y=0;
 
	}
	if(x==eposx&&y==eposy){
		eposx=(rdm.nextInt(20)*10+10);
		eposy=(rdm.nextInt(20)*10+10);
	}
		repaint();
	}
	public void paintComponent(Graphics g){
		g.setColor(Color.WHITE);
		g.fillRect(0,0,100000,10000000);
		g.setColor(Color.BLACK);
		g.fillOval(x,y,10,10);
		g.setColor(Color.GREEN);
		g.fillOval(x1,y1,10,10);
		g.setColor(Color.RED);
		g.fillRect(eposx,eposy,10,10);
 
	}
	public void keyPressed(KeyEvent e){
		tmr.start();
		int c = e.getKeyCode();
		if(c==KeyEvent.VK_RIGHT&&rmove==true){
			right=true;
			left=false;
			up=false;
			down=false;
			umove=true;
			dmove=true;
			lmove=false;
			rmove=false;
 
		}
		if(c==KeyEvent.VK_LEFT&&lmove==true){
			right=false;
			left=true;
			up=false;
			down=false;
			rmove=false;
			lmove=true;
			umove=true;
			dmove=true;
 
		}
		if(c==KeyEvent.VK_UP&&umove==true){
			right=false;
			left=false;
			up=true;
			down=false;
			umove=true;
			dmove=false;
			lmove=true;
			rmove=true;
 
		}
		if(c==KeyEvent.VK_DOWN&&dmove==true){
			right=false;
			left=false;
			up=false;
			down=true;
			umove=false;
			dmove=true;
			lmove=true;
			rmove=true;
 
		}
		repaint();
 
	}
	public void keyTyped(KeyEvent e){}
	public void keyReleased(KeyEvent e){}
 
	public static void main(String[]args){
		snake obj = new snake();	
 
	frame.setSize(300,300);
 
	frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
 
	frame.setVisible(true);
 
	frame.add(obj);	
 
	}
}

What should I add?

Originally Posted by Norm

What are the rules for playing the game?
What is supposed to happen?
What does happen?

My problem is the body of the snake, I need it to follow the snakes head, once the head of the snake moves on the position of the body, game-over. The body goes to every previous position of the head of the snake.. I don't know what to do about the body part..

Here's how it works the Black oval is the head of the snake, it's followed by one green oval which is followed by one green oval. These green oval's are the body/tail of the snake. The black oval(head) keeps moving on the direction pressed, but will not move on the opposite direction if its going up it cant go down.

For example the current position of the black oval is sHeadx=150,sHeady150 , the user pressed right so it goes to the right adding(continuous) 5 to the sHeadx which makes it 155, the green oval must go to the previous location of the black oval(head) which was 150,150. The same goes for the 2nd green oval, but it follows the location of the 1st green oval.

My problem is, I don't know how to make the green ovals follow the previous position of the black oval or the head.


here's the updated.. named it properly

import java.awt.*;
import javax.swing.*;
import java.awt.event.*;
import java.awt.event.ActionEvent;
import java.util.Random;
import java.util.ArrayList;
public class snake extends JPanel implements ActionListener,KeyListener{
 
		static JFrame frame = new  JFrame();
		int sHeadx = 150,sHeady=150,eposx=200,eposy=120,score=0;
		int []sBodyx = new int[]{sHeadx-10,sHeadx-20};
		int []sBodyy = new int[] {sHeady,sHeady};
		static int slength = 3;
		boolean right = true,left=true,up=true,down=true,rmove=true,lmove=false,umove=false,dmove=false;
		Timer tmr = new Timer(50,this);
		Random rdm = new Random();
 
	public snake(){
		setLayout(null);		
		this.requestFocus();
		addKeyListener(this);
        setFocusable(true);
        setFocusTraversalKeysEnabled(false);
	}
 
 
	public void actionPerformed(ActionEvent e){
	if(e.getSource()==tmr){
 
		if(right==true&&lmove==false){
		sHeadx=sHeadx+5;
		sBodyx[0]=sHeadx-10;sBodyy[0]=sHeady;
		sBodyx[1]=sHeadx-20;sBodyy[1]=sHeady;
		System.out.println("X = " + sHeadx + " Y = " + sHeady);
		}
		if(left==true&&rmove==false){
		sHeadx=sHeadx-5;
		sBodyx[0]=sHeadx+10;sBodyy[0]=sHeady;
		sBodyx[1]=sHeadx+20;sBodyy[1]=sHeady;
			System.out.println("X = " + sHeadx + " Y = " + sHeady);
		}
		if(up==true&&dmove==false){
		sHeady=sHeady-5;
		sBodyx[0]=sHeadx;sBodyy[0]=sHeady+10;
		sBodyx[1]=sHeadx;sBodyy[1]=sHeady+20;
		System.out.println("X = " + sHeadx + " Y = " + sHeady);
 
		}
		if(down==true&&umove==false){
		sHeady=sHeady+5;
		sBodyx[0]=sHeadx;sBodyy[0]=sHeady-10;
		sBodyx[1]=sHeadx;sBodyy[1]=sHeady-20;
		System.out.println("X = " + sHeadx + " Y = " + sHeady);
		}
	}
	if(sHeadx>=280){
		sHeadx=0;
 
	}
	else if(sHeadx<=00){
		sHeadx=280;
	}
	else if(sHeady<=00){
		sHeady=260;
 
	}
	else if(sHeady>=260){
		sHeady=0;
 
	}
 
	if(sHeadx==eposx&&sHeady==eposy){
		eposx=(rdm.nextInt(20)*10+10);
		eposy=(rdm.nextInt(20)*10+10);
		score=score+10;
		System.out.println("CURRENT SCORE : "+score);
	}
		repaint();
	}
	public void paintComponent(Graphics g){
		g.setColor(Color.WHITE);
		g.fillRect(0,0,100000,10000000);
		g.setColor(Color.BLACK);
		g.fillOval(sHeadx,sHeady,10,10);
		g.setColor(Color.GREEN);
		g.fillOval(sBodyx[0],sBodyy[0],10,10);//1st green dot
		g.fillOval(sBodyx[1],sBodyy[1],10,10);//2nd green dot
		g.setColor(Color.RED);//Food 
		g.fillRect(eposx,eposy,10,10);//Food Position
 
	}
	public void keyPressed(KeyEvent e){
		tmr.start();
		int c = e.getKeyCode();
		if(c==KeyEvent.VK_RIGHT&&rmove==true){
			right=true;
			left=false;
			up=false;
			down=false;
			umove=true;
			dmove=true;
			lmove=false;
			rmove=false;
 
		}
		if(c==KeyEvent.VK_LEFT&&lmove==true){
			right=false;
			left=true;
			up=false;
			down=false;
			rmove=false;
			lmove=true;
			umove=true;
			dmove=true;
 
		}
		if(c==KeyEvent.VK_UP&&umove==true){
			right=false;
			left=false;
			up=true;
			down=false;
			umove=true;
			dmove=false;
			lmove=true;
			rmove=true;
 
		}
		if(c==KeyEvent.VK_DOWN&&dmove==true){
			right=false;
			left=false;
			up=false;
			down=true;
			umove=false;
			dmove=true;
			lmove=true;
			rmove=true;
 
		}
		repaint();
 
	}
	public void keyTyped(KeyEvent e){}
	public void keyReleased(KeyEvent e){}
 
	public static void main(String[]args){
		snake obj = new snake();	
 
	frame.setSize(300,300);
 
	frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
 
	frame.setVisible(true);
 
	frame.add(obj);	
 
	}
}

Originally Posted by Norm

What value is in the eposx variable?

Is this too restrictive, requiring the points to be equal?

if(sHeadx==eposx&&sHeady==eposy){

Should the width of the shapes be considered?

moving to the exact position of eposx and eposy will give you a score

g.setColor(Color.RED);//Food 
g.fillRect(eposx,eposy,10,10);//Food Position

if the head of the snake goes to the exact position, you gain a score, then it changes position.

 
if(sHeadx==eposx&&sHeady==eposy){
		eposx=(rdm.nextInt(20)*10+10);
		eposy=(rdm.nextInt(20)*10+10);
		score=score+10;
		System.out.println("CURRENT SCORE : "+score);
	}

My real problem is the green ovals going to the previous positions of the black oval..