Stage 5 - Item Creation

Introduction

Now our dungeon is starting to take shape. The user can move between multiple rooms in which they can interact with different characters. We have two different types of characters, with different user interactions.

In this stage we will continue to fill out our dungeon. Most Dungeon crawlers will contain different items that the player can interact with, so let’s create some items.

To achieve this we will:

  • Define an Item class

  • Create Item objects

  • Add the Item objects to the rooms

  • Include the Item objects in the room description.

Class Diagram

The new class diagram shows our new Items class, as well as the new item attribute in our Room class.

lesson 5 class diagram

Define the Item class

In Thonny create a new file and enter the code below. Then save it as item.py in the same folder as main.py, character.py and room.py.

1# item.py
2
3class Item():
4    
5    def __init__(self,name):
6        # initialise the Item object
7        self.name = name.lower()
8        self.description = None

In investigating the code everything should be familiar:

  • defining the Item class

  • defining our __init__ method

  • assigning the name argument to the self.name attribute

  • creating a placeholder self.description attribute to be assigned a value later

Create Item objects

To create the Item objects, move to the main.py file and add the code below:

 1# main.py
 2
 3from room import Room
 4from character import Enemy, Friend
 5from item import Item
 6
 7# create rooms
 8cavern = Room("Cavern")
 9cavern.description = ("A room so big that the light of your torch doesn’t reach the walls.")
10
11armoury = Room("Armoury")
12armoury.description = ("The walls are lined with racks that once held weapons and armour.")
13
14lab = Room("Laboratory")
15lab.description = ("A strange odour hangs in a room filled with unknownable contraptions.")
16
17# link rooms
18cavern.link_rooms(armoury,"south")
19armoury.link_rooms(cavern,"north")
20armoury.link_rooms(lab,"east")
21lab.link_rooms(armoury,"west")
22
23# create characters
24ugine = Enemy("Ugine")
25ugine.description = "a huge troll with rotting teeth."
26ugine.weakness = "cheese"
27
28nigel = Friend("Nigel")
29nigel.description = "a burly dwarf with golden bead in woven through his beard."
30nigel.conversation = "Well youngan, what are you doing here?"
31
32# add characters to rooms
33armoury.character = ugine
34lab.character = nigel
35
36# create items
37cheese = Item("Cheese")
38cheese.description = "super smelly"
39
40chair = Item("Chair")
41chair.description = "designed to be sat on"
42
43elmo = Item("Elmo")
44elmo.description = "wanting to be tickled"
45
46'''
47# describe the rooms
48cavern.describe()
49armoury.describe()
50lab.describe()
51'''
52
53# initialise variables
54running = True
55current_room = cavern
56
57# ----- MAIN LOOP -----
58while running:
59    current_room.describe()
60    
61    command = input("> ").lower()
62    
63    if command in ["north", "south", "east", "west"]:
64        current_room = current_room.move(command)
65    elif command == "talk":
66        if current_room.character is not None:
67            current_room.character.talk()
68        else:
69            print("There is no one here to talk to")
70    elif command == "hug":
71        if current_room.character is not None:
72            current_room.character.hug()
73        else:
74            print("There is no one here to hug")
75    elif command== "fight":
76        if current_room.character is not None:
77            weapon = input("What will you fight with? > ").lower()
78            if current_room.character.fight(weapon):
79                current_room.character = None
80            else:
81                running = False
82        else:
83            print("There is no one here to fight")
84    elif command == "quit":
85        running = False
86    else:
87        print("I don't understand.")

Predict what you think will happen and run the code.

Again, in investigating the code this should all be familiar.

For each of the items, we have:

  • imported our new class (Item)

  • called Item() to create a Item object and then assigned it to a variable

  • assigned a string to the Item object’s description attribute

Add the item object to the the rooms.

To add the Item objects to the rooms, we need to first adjust the Room class, so go to room.py and add the code below.

 1# room.py
 2
 3class Room():
 4    
 5    def __init__(self,room_name):
 6        # initialises the room object
 7        self.name = room_name.lower()
 8        self.description = None
 9        self.linked_rooms = {}
10        self.character = None
11        self.item = None
12        
13    def describe(self):
14        # sends a description of the room to the terminal
15        print(f"\nYou are in the {self.name}")
16        print(self.description)
17        if self.character is not None:
18            self.character.describe()
19        for direction in self.linked_rooms.keys():
20            print(f"To the {direction} is the {self.linked_rooms[direction].name}")
21    
22    def link_rooms(self, room_to_link, direction):
23        # links the provided room, in the provided direction
24        self.linked_rooms[direction.lower()] = room_to_link
25        
26    def move(self, direction):
27        # returns the room linked in the given direction
28        if direction in self.linked_rooms.keys():
29            return self.linked_rooms[direction]
30        else:
31            print("You can't go that way")
32            return self

Save the room.py file and then return to the main.py file, add the highlighted code:

 1# main.py
 2
 3from room import Room
 4from character import Enemy, Friend
 5from item import Item
 6
 7# create rooms
 8cavern = Room("Cavern")
 9cavern.description = ("A room so big that the light of your torch doesn’t reach the walls.")
10
11armoury = Room("Armoury")
12armoury.description = ("The walls are lined with racks that once held weapons and armour.")
13
14lab = Room("Laboratory")
15lab.description = ("A strange odour hangs in a room filled with unknownable contraptions.")
16
17# link rooms
18cavern.link_rooms(armoury,"south")
19armoury.link_rooms(cavern,"north")
20armoury.link_rooms(lab,"east")
21lab.link_rooms(armoury,"west")
22
23# create characters
24ugine = Enemy("Ugine")
25ugine.description = "a huge troll with rotting teeth."
26ugine.weakness = "cheese"
27
28nigel = Friend("Nigel")
29nigel.description = "a burly dwarf with golden bead in woven through his beard."
30nigel.conversation = "Well youngan, what are you doing here?"
31
32# add characters to rooms
33armoury.character = ugine
34lab.character = nigel
35
36# create items
37cheese = Item("Cheese")
38cheese.description = "super smelly"
39
40chair = Item("Chair")
41chair.description = "designed to be sat on"
42
43elmo = Item("Elmo")
44elmo.description = "wanting to be tickled"
45
46# add items to rooms
47cavern.item = chair
48armoury.item = elmo
49lab.item = cheese
50
51'''
52# describe the rooms
53cavern.describe()
54armoury.describe()
55lab.describe()
56'''
57
58# initialise variables
59running = True
60current_room = cavern
61
62# ----- MAIN LOOP -----
63while running:
64    current_room.describe()
65    
66    command = input("> ").lower()
67    
68    if command in ["north", "south", "east", "west"]:
69        current_room = current_room.move(command)
70    elif command == "talk":
71        if current_room.character is not None:
72            current_room.character.talk()
73        else:
74            print("There is no one here to talk to")
75    elif command == "hug":
76        if current_room.character is not None:
77            current_room.character.hug()
78        else:
79            print("There is no one here to hug")
80    elif command== "fight":
81        if current_room.character is not None:
82            weapon = input("What will you fight with? > ").lower()
83            if current_room.character.fight(weapon):
84                current_room.character = None
85            else:
86                running = False
87        else:
88            print("There is no one here to fight")
89    elif command == "quit":
90        running = False
91    else:
92        print("I don't understand.")

Predict what you think will happen and then run the program.

Investigating this code, and it will all look familiar to you.

For each item we assigned it to the item attribute of a Room object.

Include the Item objects in the room description

Despite writing all this code, your program should run the same as when we started. That’s because none of these changes have been outputted. For the Item objects we are going to follow the same process that we did for the Character objects:

  • create a describe method in the Item class

  • call the Item describe method from the Room describe method

First we need to go to the item.py file and add the code below:

 1# item.py
 2
 3class Item():
 4    
 5    def __init__(self,name):
 6        # initialise the Item object
 7        self.name = name.lower()
 8        self.description = None
 9
10    def describe(self):
11        # prints description of item to the terminal
12        print(f"You see {self.name} in the room. It is {self.description}.")

In investing this code, you should already recognise all the elements:

  • defining method

  • method describing comment

  • display to terminal using attributes of the object.

Now head to room.py and add the following code:

 1# room.py
 2
 3class Room():
 4    
 5    def __init__(self,room_name):
 6        # initialises the room object
 7        self.name = room_name.lower()
 8        self.description = None
 9        self.linked_rooms = {}
10        self.character = None
11        self.item = None
12        
13    def describe(self):
14        # sends a description of the room to the terminal
15        print(f"\nYou are in the {self.name}")
16        print(self.description)
17        if self.character is not None:
18            self.character.describe()
19        if self.item is not None:
20            self.item.describe()
21        for direction in self.linked_rooms.keys():
22            print(f"To the {direction} is the {self.linked_rooms[direction].name}")
23    
24    def link_rooms(self, room_to_link, direction):
25        # links the provided room, in the provided direction
26        self.linked_rooms[direction.lower()] = room_to_link
27        
28    def move(self, direction):
29        # returns the room linked in the given direction
30        if direction in self.linked_rooms.keys():
31            return self.linked_rooms[direction]
32        else:
33            print("You can't go that way")
34            return self

Predict and run the code.

Investigate the code and you will notice that it is very similar to the character description:

  • check if there is an item in the room

  • when an item is present, call it’s describe method.

Go a step further and test the code by going to each room and checking that the correct item is displayed.

Room

Item expected

Item described

Cavern

chair

Armoury

elmo

Lab

cheese

Stage 5 task

Now it is time for your to implement the Make phase.

You should:

  • make an additional item for each of your additional rooms

  • add your additional items to their room.