Stop at Walls

At the moment, it is easy to run off the screen, crashing the program. In this exercise, you will add walls that stop the player, also making the dungeon more interesting.

To make the walls work, you need to take care of the following:

1. add walls to the dungeon map

2. draw the walls

3. make sure the player cannot move into a wall

Add walls to the dungeon map

The data structure we created for the floor tiles makes it easy to edit the dungeon. All you need to do is add walls to the level in the start_game() function. Use the hash symbol #.

Replace a few of the floor symbols by walls, e.g. creating a border. The size of the dungeon should not change.

Hint

Running the game should work, but you won’t see anything.

Draw the walls

To see the walls, you need the image wall.png. In the draw() function in main.py, you need to distinguish between floors and walls. The logic you need to add is the following:

1. go through all tiles in the level (we have this already)

2. if the tile is a floor, draw floor.png

3. if the tile is a wall, draw wall.png

Add the following lines, replacing the one inside the two loops in draw():

if tile == ".":
    draw_tile(frame, x=x, y=y, image=images["floor"])

Hint

When you run the code, you should notice that some floor tiles are missing:

Now, add a second if statement similar to the first one that draws the walls.

Hint

The result should look like this:

Stop at walls

Currently, the player can move through the walls. Let’s stop them. You need the following logic:

1. calculate the new position where the player would move

2. if there is a floor in the new position, move there

3. if there is a wall, do nothing

You need to implement this logic in the move_player() function.

First, copy the current position of the player:

def move_player(game, direction: str) -> None:
    """Things that happen when the player walks on stuff"""
    new_x = game.x
    new_y = game.y
    ...

Second, modify the if statements so that they modify the new position instead:

if direction == "right":
    new_x += 1
...

Hint

At this point, the game should work, but you can still walk into walls.

Third, check for floors in the new position. For that you need to look up a tile in game.level. Use indexing, indicated by the square brackets. Note that the y coordinate goes first:

if game.level[new_y][new_x] == ".":
    game.x = new_x
    game.y = new_y

If the tile contains a wall, game.x and game.y will not get updated. So nothing happens.

Hint

Run the game. You should see that the player cannot move into walls any more.

Extra: Fountain

Add another element to the dungeon, e.g. a fountain using the image fountain.png.