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SWEN20003 Object Oriented Software Development Project 1, Semester 1, 2021
The University of Melbourne
School of Computing and Information Systems
SWEN20003 Object Oriented Software Development
Project 1, Semester 1, 2021
Released: 2/4/2021
Due: 23/4/2021 at 20:59 AEST
Overview
Welcome to the first project for SWEN20003! In this project, you will design and simulate ShadowTreasure,
a treasure hunt game, continuously in Projects 1 and 2. In this project (Project 1),
you will create the graphical interface and implement the interactions between the characters in
the game. These will form the basis for the game development in Project 2.
This is an individual project. You may discuss it with other students, but all of the implementation
must be your own work. You may use any platform and tools you wish to develop the project,
but we officially support IntelliJ IDEA for Java development.
The purpose of this project is to:
• give you experience working with an object-oriented programming language (Java)
• introduce fundamental game programming concepts (e.g., 2D graphics, geometric calculations)
• give you experience writing software using an external library (Bagel)
Bagel Concepts
The Basic Academic Graphical Engine Library (Bagel) is a game engine that you will use to develop
your simulation. You can find the documentation for Bagel here—please check this documentation
first if you need clarification on how to use the library.
Every coordinate on the screen is described by an (x, y) pair. (0, 0) represents the top-left of the
screen, and coordinates increase towards the bottom-right. Each of these coordinates is called a
pixel. The Bagel Point class encapsulates this, and additionally allows floating-point positions to
be represented. Note that, in the rest of the context, we omit the entity“pixel”of any
metric amount. For example,“the step size is 10”means the step size is 10 pixel.1
Many times per second, the program’s logic is updated, the screen is cleared to a blank state, and
all of the graphics are rendered again. Each of these steps is called a frame. Every time a frame
is to be rendered, the update method of AbstractGame is called. It is in this method that you are
expected to update the state of the simulations.
1This means, when you write java code, you don’t need to worry about the entity, just set the value to 10, e.g.,
STEP_SIZE = 10.
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SWEN20003 Object Oriented Software Development Project 1, Semester 1, 2021
Figure 1: An Example of Project 1 Screenshot (note that the position of player, sandwich and
zombie might be different in your implementation).
The simulation state must change only every 10 frames; this is called a tick. That is, counting
the number of frames from 1 (at the beginning of the game), the updates of all objects (including
status/variable value changes and movements) should only happen in the frame number that is an
integer multiple of 10, e.g., 10, 20, 30, ….
Figure 1 shows a screenshot from the simulation after completing Project 1.
Treasure Hunt Game
The Player enters a tomb to search for a treasure box. The tomb is filled with zombies, that the
Player needs to fight before reaching the treasure. While the fighting is energy-consuming, the
tomb is also filled with the nutritious foods to let the Player regain strength.
In Project 1, you will implement three entities: the Player; a zombie; and a sandwich; and the basic
interactions between them. There is only one player in the treasure hunt game. For Project 1,
there is one zombie and one sandwich. The character and function descriptions of the Player,
zombie and sandwich are outlined below.
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SWEN20003 Object Oriented Software Development Project 1, Semester 1, 2021
(a) Zombie (b) Sandwich (c) Player
Figure 2: Images of Characters in ShadowTreasure
Background
There is a static background that should be rendered below all of the other elements, and will not
change. The image for the background is located at res/images/background.png. It should be
rendered so that its top-left is at the coordinate (0, 0).
Entities
The Player (described below), can interact with other entities in the tomb. In Project 1, you need
to implement two types of stationary entities (in addition to the Player): a zombie and a sandwich.
• Zombie: a stationary entity in the tomb. Its image is located at res/images/Zombie.png.
See Figure 2(a).
• Sandwich: a stationary entity that provides nutrition to the Player. Its image is located at
res/images/Sandwich.png. See Figure 2(b).
Player
The Player is an entity with an associated image res/images/player.png. See Figure 2(c). The
Player has the following attributes:
• Energy: an int attribute that indicates the energy level of the Player. The energy level is
updated when the Player interacts with the entities (zombie and sandwich), according to
Algorithm 1. The energy level should be displayed in black at position (20, 760) in the form
of
energy: [energy level]
in size 20 and font DejaVuSans-Bol (use the file DejaVuSans-Bold.ttf provided in the res.zip
file). See Figure 1.
• Step size: The Player has step size 10 indicating the distance she moves when she moves one
step.
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SWEN20003 Object Oriented Software Development Project 1, Semester 1, 2021
Algorithm 1: Interaction Logic and Energy Update of Player in Each Tick
1 if the Player meets a zombie then
2 the Player is frighted by the zombie and her energy level is reduced by 3. The treasure
hunt game will be terminated.2
3 else if the Player meets a sandwich then
4 the Player eats the sandwich, which increases her energy level by 5. The sandwich will
disappear from the screen.
5 endif
6 if the Player’s energy level ≥ 3 then
7 the Player moves towards the zombie by one step.
8 else
9 the Player moves towards sandwich by one step.
10 endif
Initial Positions
The initial positions of the entities are determined by a environment file, located at res/environment.csv.
This is a comma-separated value (CSV) file with rows in the following format for zombie and sandwich:
[Type], x-coordinate, y-coordinate
where the [Type] is Zombie or Sandwich respectively and the x-coordinate and y-coordinate show
the location of the entity.
A row in the file for the Player will have the format:
Player, x-coordinate, y-coordinate, energy level
where x-coordinate and y-coordinate show the initial location of the Player and the last column,
energy level, shows the starting energy level of the Player. The environment file we provided in the
zip file has the following content:
Player,650,100,2
Zombie,300,200
Sandwich,500,400
This means that you should render the Player, a zombie and a sandwich at position (650, 100),
(300, 200) and (500, 400), respectively, at the beginning of the game. The Player’s initial energy
level is 2.
You must actually load the environment file—copying and pasting the data, for example, is
not allowed. You must load this environment file and create the corresponding entities in your
simulation. When we testing your code, we may use a different environment file.
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SWEN20003 Object Oriented Software Development Project 1, Semester 1, 2021
Algorithm 1: Interactions between the Player and other entities and energy update
The Player has strong radar that collects the information (type and position of other entities) in
the game. She should interact and set/change the direction of her movement in each tick according
to Algorithm 1. See the following notes for Algorithm 1.
• Definition of’meet’: In lines 1 and 3, the Player is considered to meet to an entity (zombie
or sandwich), if the Euclidean distance between the Player and the entity is (strictly) less
than 50. Recall that Euclidean distance between (x1, y1) and (x2, y2) is
dist = p
(x1 − x2)
2 + (y1 − y2)
2.
• One-step move: Refer to the solutions to workshop questions in Week 5 for how to make
the Player move by one step in lines 7 and 9. Note, the direction should be normalized so
that the length of each move is 10.3 All related information is provided in the solutions to
Week 5 workshop.
Output
It is required that you trace and output the Player’s movement. You need to print to the standard
output (stdout), i.e., the screen/console, the position the Player moves to and her energy level in
each tick, including the initial position and energy level (as readfrom the environment file), in the
form of
x-coordinate, y-coordinate, energy level
in one line for each tick.
Use the method with the following signature:
public static void printInfo(double x, double y, int e)
in the class ShadowTreasure, in the skeleton code provided (described later), to print the position
of the Player.
Note: You should make sure you write to stdout correctly in each tick. We will read
the stdout when we check the functionality of your code.
Your Code
You are required to submit the following:
• a class named ShadowTreasure that contains a main method to run the simulation described
above
2
In project2, you will be asked to make the Player fight with the zombie. But, you don’t need implement this
part in project 1.
3When you look into it, apply some tolerance: 10 ±0.1. This is also the tolerance we will apply when we test your
code.
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SWEN20003 Object Oriented Software Development Project 1, Semester 1, 2021
• and all other classes you have designed and implemented to make the game work.
You may choose to create as many additional classes as you see fit, keeping in mind the principles
of object oriented design discussed so far in the subject. You will be assessed based on your code
running correctly, as well as the effective use of Java concepts. As always in software engineering,
appropriate comments and variables/method/class names are important.
Implementation Checklist
To help you get started, here is a checklist of the required functionality, with a suggested order of
implementation:
• Draw the background on screen.
• At the beginning of the game, load the environment file and draw the Player, a zombie and
a sandwich at the designated position on screen.
• Implement Algorithm 1.
Supplied Package
You will be given a package project-1.zip, which contains: (1) Skeleton code for the ShadowTeasure.java
class in the res folder to help you get started – this class also has the method to print the Player
information as described above; (2) All of the graphics and other files you need to build the game in
the res folder; (3) Input and output files for two test scenarios in the test folder; and (4) pom.xml
file required for Maven. Below is a more detailed description of its contents:
• src/ – The folder for the code.
– ShadowTreasure – Skeleton code for a game.
• test/
– test1/ – the sample video in Canvas shows the game simulation for test1
∗ environment.csv: The environment file, the same file as in res/IO/environment.csv.
∗ output.csv: The output that is expected to display on the screen after you load
environment.csv and run ShadowTreasure.
– test2/
∗ environment.csv: The environment file.
∗ output.csv: The output that is expected to display on the screen when you load
environment.csv and run ShadowTreasure.
• res/ – The resources for the simulation.
– images/ – The image files for the simulation.
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SWEN20003 Object Oriented Software Development Project 1, Semester 1, 2021
∗ background.png: The background image
∗ zombie.png: The image for the zombie
∗ sandwich.png: The image for the sandwich
– IO/ – The input/output files for treasure hunt game.
∗ environment.csv: The environment file.
– font/ – The font files for the simulation.
∗ DejaVuSans-Bold.ttf: The fond file.
Make sure you do not change anything in sub-directories images/ and font/: We may load
res/ in your submission when testing your code.
Note: To get started with the project, clone the [user-name]-project-1 project from
GitLab, copy the contents of this zip file to [user-name]-project-1 folder in your machine
and add, commit and push the initial code. Then start implementing the project
(adding code to meet the requirements of the specification). Please remember to add,
commit and push as you add code regularly as you progress, adding meaningful comments
for your commits.
Testing: Test your code by running the game ShadowTreasure with at least the two environment.csv
files provided in test1 and test2 sub-folders under the test folder in the supplied package, and
then compare the output with the output.csv in the respective folders.
Note: Please do additional testing as needed. When marking, we will be testing your code with
other input files.
Submission and marking
Technical requirements
• The program must be written in the Java programming language.
• The program must not depend upon any libraries other than the Java standard library and
the Bagel library (as well as Bagel’s dependencies).
• The program must compile fully without errors.
Submission will take place through GitLab. You are to submit to your <username>-project-1
repository. An example repository has been set up here showing an ideal repository structure.
At the bare minimum you are expected to follow the following structure. You can create more
files/directories in your repository.
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SWEN20003 Object Oriented Software Development Project 1, Semester 1, 2021
username -project-1
res
resources used for project
src
ShadowTreasure.java
other Java files, including at least one other class
On 23/4/2021 at 21:00 AEST, your latest commit will automatically be harvested from GitLab.
Commits
You are free to push to your repository post-deadline, but only the latest commit on or before
23/04/2021 at 20:59 AEST will be marked. You must make at least 4 commits throughout the development
of the project, and they must have meaningful messages (commit messages must match
the code in the commit). If commits are anomalous (e.g. commit message does not match the
code, commits with a large amount of code within two commits which are not far apart in time)
you risk penalization.
Examples of good, meaningful commit messages:
• displayed background and load the Player, zombie and sandwich graphics correctly
• implemented the Player’s movement logic (Algorithm 1) correctly
• refactored code for cleaner design
Examples of bad, unhelpful commit messages:
• fesjakhbdjl
• i’m hungry
• fixed thingzZZZ
Good Coding Style
Good coding style is a contentious issue; however, we will be marking your code based on the
following criteria:
• You should not go back and comment your code after the fact. You should be commenting
as you go. (Yes, we can tell.)
• You should be taking care to ensure proper use of visibility modifiers. Unless you have a very
good reason for it, all instance variables should be private.
• Any constant should be defined as a static final variable. Don’t use magic numbers!
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SWEN20003 Object Oriented Software Development Project 1, Semester 1, 2021
– A string value that is used once and is self-descriptive (e.g. a file path) does not need
to be defined as a constant.
• Think about whether your code is written to be easily extensible via appropriate use of classes.
• Make sure each class makes sense as a cohesive whole. A class should have a single well-defined
purpose, and should contain all the data it needs to fulfil this purpose.
Extensions and late submissions
If you need an extension for the project, please email Ni Ding at ni.ding@unimelb.edu.au explaining
your situation with some supporting documentation (medical certificate, academic adjustment
plan, wedding invitation). If an extension has been granted, you may submit via Gitlab as usual;
please do however email Ni Ding once you have submitted your project.
The project is due at 20:59 AEST sharp. Any submissions received past this time (from 21:00
AEST onwards) will be considered late unless an extension has been granted. There will be no
exceptions. There is a penalty of 1 mark for a late project, plus an additional 1 mark per 24 hours.
If you submit late, you must email Ni Ding so that we can ensure your late submission is marked
correctly.
Marks
Project 1 is worth 8 marks out of the total 100 for the subject.
• Features implemented correctly – 4 marks
– Background rendered correctly; Player, zombie and sandwich are rendered correctly
according to the environment file: 1 mark
– Player movement and interaction logic (see Algorithm 1) is correct: 3 marks
∗ Correct interaction with zombie and sandwich, e.g., turning direction, etc., when
she meets another entity: 1 mark;
∗ energy level is updated correctly: 0.5 mark;
∗ Move towards correct direction, when she does not meet another entity: 1 mark;
∗ Correct step size: 0.5 mark.
• Code (coding style, documentation, good object-oriented principles) – 4 marks
– Delegation – breaking the code down into appropriate classes: 1 mark
– Use of methods – avoiding repeated code and overly long/complex methods: 1 mark
– Cohesion – classes are complete units that contain all their data: 1 mark
– Code style – visibility modifiers, consistent indentation, lack of magic numbers, commenting,
etc.: 1 mark