AH HA! Never mind this question, I figured it out with the help of another thread here in the forum. Now I have a new question: I need to make the tiles on my game "obstacles" so that no enemy or hero can walk through them. I would like to have a blanket code encompass every tile on the game, meaning that any and all tiles are obstacles and cannot be walked over or under. I'm searching for an answer right now. I know how to implement collision detection, but I don't know how to tell my hero to NOT go into the tiles.

Sounds suspiciously like, "This should be obvious." Lol. I've been looking. I can see plenty of collision detection methods, but I can't seem to place my finger on a method that will prevent the mixing of two objects.

I'm hoping that I don't have to specify to my moving classes that if they hit a Tile they'll need to reverse their direction, or some such. That's busy work code. There's got to be a method that just prevents actors from intersecting altogether...

I have found a solution, though it's not the solution I was hoping for. Greenfoot doesn't seem to have any sort of a "prevent intersection" method, so for the time being I'm just telling each moving character to negate their speed when they hit a Tile. Again, not the solution I was hoping for.. but acceptable.

The Actor class does have a 'getOneObjectAtOffset(dx, dy, class)' method and a 'getObjectsAtOffset(dx, dy, class)' method which could be used for just that purpose.

You could also store the current location of your Hero(,each moving Charakter, whatever) with methods like getX(), getY() and eventually getRotation(). After the Hero takes one step you check for Collision and restore his old position with methods like setLocation(), setRotation().

Sorry, I did understand, that he wants to make every Tile an obstacle ( not passable by an character or something else). What I posted would have the effect in game, as you wouldn't see how the charakter moves a bit into the obstacle and is then set back. Sorry, for misleading hints, if I misunderstood ^^

JimmyFake, thanks for the help. It seems that the option I'm using is the best one for now, although it does have drawbacks. My hero and enemies occasionally get "stuck" on the side of the tiles. For instance, if I approach the square tile from above, touch it, then immediately turn left or right, I can't move. I have to move upwards a pinch to free up the character. It's not perfect, but any attempt to set the character back a pinch results in the occasional bug of enemies and the hero getting stuck, then turning around, then passing slowly through the tiles. It's so awkward. Lol.

The game is shaping up pretty nicely! I'm very proud even if it is not really much of a game. For my second game ever, it's not too bad. The hero can now move seamlessly between 9 areas, with 4 different monsters, one item to pick up, and even some music I added. I'm having a good time with this.