Please refer to my Scrolling Tutorial scenario.

Thanks I appreciate your help. I used your Tutorial as main reference and I still encountered a few Issues.( I'm trying to do an Actor follow Scrolling code) I can't find a symbol for both the Scroller, Player() and the Scroll. My scrollactor is Megaman import greenfoot.*; // (World, Actor, GreenfootImage, Greenfoot and MouseInfo) /** * Write a description of class Sky here. * * @author (your name) * @version (a version number or a date) */ public class Sky extends World { public static final int WIDE = 1200; public static final int HIGH =540; public static final int CELL =1; Scroller scroller; Actor Megaman; public Sky() { super(WIDE, HIGH, CELL, false); addObject( new Megaman(), 0, 100); addObject( new Boost(), 600, 300); scroller = new Scroller(); GreenfootImage bg = new GreenfootImage("Unknown.jpeg"); int bgWide = bg.getWidth(); int bgHigh = bg.getHeight(); scroller= new Scroller(this, bg, bgWide, bgHigh); Megaman = new Player(); addObject( Megaman, bgWide/2, bgHigh/2); scroll(); } public void act() { if( Megaman!=null)scroll(); } { int dsx = Megaman.getX()-WIDE/2; int dsy = Megaman.getY()-HIGH/2; scroller.scroll(dsx,dsy); } } That's my code if that may help you.

The following should be closer to what you need:

I'm still having a problem with the bgWide, bgHigh and the Scroller. It can't find the Symbols.

Sorry -- lines 9 and 10 were both supposed to start with 'int'.

Oh okay thanks that resolves all problems except for the Scroller it still hasn't got a symbol.

Did you add my Scroller class to your scenario?

Okay i found it thanks. But I can now launch my game but it doesn't follow my megaman. ( Thanks for taking so much time for me by the way). Thats my code for the bg : import greenfoot.*; // (World, Actor, GreenfootImage, Greenfoot and MouseInfo) /** * Write a description of class Sky here. * * @author (your name) * @version (a version number or a date) */ public class Sky extends World { public static final int WIDE = 1200; public static final int HIGH =540; public static final int CELL =1; Scroller scroller; Actor Megaman; public Sky() { super( WIDE, HIGH, CELL, false); GreenfootImage bg = new GreenfootImage("Unknown.jpeg"); int bgWide = bg.getWidth(); int bgHigh = bg.getHeight(); scroller = new Scroller(this, bg, bgWide, bgHigh); Megaman = new Megaman(); addObject(Megaman, bgWide/2, bgHigh/2); scroll(); } public void act() { if (Megaman != null && Megaman.getWorld() == this) scroll(); } private void scroll() { int dsx = Megaman.getX()-WIDE/2; int dsy = Megaman.getY()-HIGH/2; scroller.scroll(dsx, dsy); } } and i took this one for the Scroller import greenfoot.*; /** * CLASS: Scroller (extends Object) * AUTHOR: danpost (greenfoot.org username) * DATE: November 11, 2016 * MODIFIED: December 22, 2016 (fixed 'scroll' method for limited no-image scrolling) * MODIFIED: February 21, 2017 (fixed scroll offsets for unlimited no-image scrolling) * * DESCRIPTION: This is a support class for a scrolling world. It contains two constructors; * one for unlimited scrolling and one for limited scrolling. Both constructors have an 'image' * parameter. Because image manipulation can hog up CPU time, it is important to remember that * it is better not to have a scrolling background image (having an Actor for the background is * probably worse than having the background scroll). For unlimited scrolling using a background * image, the smaller that background image to be tiled, the better. Making the viewport (the * size of the world that is visible) smaller can help in CPU expense, also. Scrolling worlds * should be unbounded, allowing actors to move beyond the visible area. Ensuring that actors * are removed from the world if no longer needed when out of view will help to prevent lag, * as well. * * It is the responsibility of the World object that creates a Scroller object to determine when * to scroll and by how much. */ public class Scroller { private World world; // view window world private GreenfootImage scrollImage; // scrolling image private boolean limited; // flag to indicate whether scrolling is limited or not private int scrolledX, scrolledY; // current scrolled distances private int wide, high; // if limited, dimensions of scrolling area else of image to wrap /** * This constructor is for an unlimited scrolling world; * If 'image' is null, the background will not change; else the given image is wrapped * * @param viewWorld the world that scrolling will be performed on * @param image the background image that will be tiled, if needed, and wrap with scrolling */ public Scroller(World viewWorld, GreenfootImage image) { world = viewWorld; scrollImage = image; if (image != null) { wide = image.getWidth(); high = image.getHeight(); } scroll(0, 0); // sets initial background image } /** * This constructor is for a limited scrolling world; * If 'image' is smaller than the given total scrolling area, it will be tiled * If 'image' is null, the background will not change * * @param viewWorld the world that scrolling will be performed on * @param image the background image that will be tiled, if needed, to fill the scrolling area * @param wide the width of the visible area encompassed through scrolling; * the given value must be at least equal to the width of 'viewWorld' and * is given in world cells (not in pixels) * @param high the height of the visible area encompassed through scrolling; * the given value must be at least equal to the height of 'viewWorld' and * is given in world cells (not in pixels) */ public Scroller(World viewWorld, GreenfootImage image, int wide, int high) { this.wide = wide; this.high = high; limited = true; world = viewWorld; if (image != null) { // create an image as large as scrolling area; tiled, if needeed scrollImage = new GreenfootImage(wide*world.getCellSize(), high*world.getCellSize()); for (int x=0; x<wide*world.getCellSize(); x+= image.getWidth()) for (int y=0; y<high*world.getCellSize(); y+=image.getHeight()) scrollImage.drawImage(image, x, y); // set initial background image scroll(0, 0); } } /** * performs scrolling on 'world' by the given distances along the horizontal and vertical; * if 'limited' is false, requested distances are actual scrolling distances; * if 'limited' is true, the distances may be adjusted due to the limits of scrolling * * @param dsx the requested distance to shift everything horizontally * @param dsy the requested distance to shift everything vertically */ public void scroll(int dsx, int dsy) { // adjust scroll amounts and scroll background image if (limited) { // calculate limits of scrolling int maxX = wide-world.getWidth(); int maxY = high-world.getHeight(); // apply limits to distances to scroll if (scrolledX+dsx < 0) dsx = -scrolledX; if (scrolledX+dsx >= maxX) dsx = maxX-scrolledX; if (scrolledY+dsy < 0) dsy = -scrolledY; if (scrolledY+dsy >= maxY) dsy = maxY-scrolledY; // update scroll positions scrolledX += dsx; scrolledY += dsy; // scroll background image if (scrollImage != null) { world.getBackground().drawImage ( scrollImage, -scrolledX*world.getCellSize(), -scrolledY*world.getCellSize() ); } } else // unlimited image wrapping { // update scroll positions scrolledX += dsx; scrolledY += dsy; // scroll background image if (scrollImage != null) { // create working variables of scroll positions int imageX = scrolledX*world.getCellSize(); int imageY = scrolledY*world.getCellSize(); // get near-zero starting positions for drawing 'scrollImage' imageX = imageX%wide; imageY = imageY%high; // adjust negative values as needed if (imageX < 0) imageX += wide; if (imageY < 0) imageY += high; // create image of appropriate size and tile fill 'scrollImage' onto it GreenfootImage hold = new GreenfootImage(scrollImage); hold.drawImage(scrollImage, -imageX, -imageY); if (imageX > 0) hold.drawImage(scrollImage, wide-imageX, -imageY); if (imageY > 0) hold.drawImage(scrollImage, -imageX, high-imageY); if (imageX > 0 && imageY > 0) hold.drawImage(scrollImage, wide-imageX, high-imageY); // set image to background of 'world' world.setBackground(hold); } } // adjust position of all actors (that can move with 'setLocation') for (Object obj : world.getObjects(null)) { Actor actor = (Actor) obj; actor.setLocation(actor.getX()-dsx, actor.getY()-dsy); } } /** * getter method for the current total scrolled distance horizontally * * @return the current total offset of horizontal scrolling */ public int getScrolledX() { return scrolledX; } /** * getter method for the current total scrolled distance vertically * * @return the current total offset of vertical scrolling */ public int getScrolledY() { return scrolledY; } }

It still doesn't work. Maybe the problem comes from the bgWide and the bgHigh because my Megaman doesn't spawn in the middle of the map (addObject(Megaman, bgWide/2, bgHigh/2);)

That would not be it. Do this -- inspect world, inspect scroller, and report back the values of wide and high.

i got for the world i got 1200 for Wide, 540 for High. and for the scroller i got no fields

There has got to be scroller fields.

Do you maybe know why i got no fields in the Scroller ? I can send u my code if it might help you. I got 2 Actors Megaman and Boost and I got 1 world Sky is the name of the world.