The bees are coming!
Create a better soldier
In this project, you will create a tower defense game called Ants Vs. SomeBees. As the ant queen, you populate your colony with the bravest ants you can muster. Your ants must protect their queen from the evil bees that invade your territory. Irritate the bees enough by throwing leaves at them, and they will be vanquished. Fail to pester the airborne intruders adequately, and your queen will succumb to the bees' wrath. This game is inspired by PopCap Games' Plants Vs. Zombies ®.
This project combines functional and object-oriented programming paradigms, focusing on the material from Chapter 2.5 of the lecture notes. The project also involves understanding, extending, and testing a large program with many related parts.
This project includes several files, but all of your changes will be made to the first two. You can download all of the project code as a zip archive.
||The game logic of Ants Vs. SomeBees.|
||A place to answer the written problems in the project.|
||A series of unit tests to test various parts of your project.|
||Graphics for Ants Vs. SomeBees.|
||General functions for displaying simple two-dimensional animations.|
||Utility functions for 61A.|
This is a two-week project. You'll work in a team of two people, person A and person B. In each part, you will do some of the work separately and some together with your partner. For example, if a problem is marked A1, then it is a solo problem for person A. Both partners should read, think about, and understand the solution to all questions.
Start early! The amount of time it takes to complete a project (or any program) is unpredictable. Ask for help early and often -- the TAs and lab assistants are here to help.
In the end, you and your partner will submit one project. Person-specific problems are graded individually and do not affect your partner's score. There are 25 possible points for each person. If you choose to work alone, you must complete the entire project, including all of the questions posed to both partners.
The only two files that you are required to submit are
written.txt. You do not need to
modify any other files in order to complete the project. To submit the project,
change to the directory where the files are located and run
This project is due by noon on Wednesday, October 19.
A game of Ants Vs. SomeBees consists of a series of turns. In each turn, new bees may enter the ant colony. Then, new ants are placed. Finally, all insects (ants, then bees) take individual actions: bees sting ants, and ants throw leaves at bees. The game ends either when a bee reaches the ant queen (you lose), or the entire bee flotilla has been vanquished (you win).
The Colony. The colony consists of several places that are chained
exit of each
Place leads to another
Placing Ants. There are two constraints that limit ant production.
Placing an ant uses up some amount of the colony's food, a different amount for
each type of ant. Also, only one ant can occupy each
Bees. When it is time to act, a bee either moves to the
exit of its current
Place if no ant blocks its path,
or stings an ant that blocks its path.
Ants. Each type of ant takes a different action and requires a
different amount of food to place. The two most basic ant types are the
HarvesterAnt, which adds one food to the colony during each turn,
ThrowerAnt, which throws a leaf at a bee each turn.
Most concepts in the game have a corresponding class that encapsulates the
logic for that concept. For instance, a
Place in the colony holds
insects and connects to other places. A
Bee stings ants and
advances through exits.
The game can be run in two modes: as a text-based game or using a graphical user interface (GUI). The game logic is the same in either case, but the GUI enforces a turn time limit that makes playing the game more exciting. The text-based interface is provided for debugging and development.
The files are separated according to these two modes.
knows nothing of graphics or turn time limits. All graphical elements are
graphics.py. It is
possible to complete this project without ever reading the graphics files.
To start a text-based game, run
To start a graphical game, run
When you start the graphical version, a new window should appear:
In the starter implementation, you have unlimited food and your ants only
throw leaves at bees in their current
Place. Try playing a game
anyway! You'll need to place a lot of
ThrowerAnts (the second type)
in order to keep the bees from reaching your queen.
You have also been provided a testing file
tests.py that runs a
series of unit tests for the project. To test your project, you can run
python3 tests.py -vThis command runs all of the unit tests along with any doctests in ants.py. The optional
-vgenerates more verbose output. If you would like to learn more about Python's built-in unit testing framework, read the documentation on the unittest module. Most problems have associated tests. Make sure that the tests for each problem pass before moving on.
Problem 1 (3 pts). Answer the following written questions in the file
written.txt after you have read the entire
runis not a method)!
Hive, a subclass of
Place, is the starting location of the bees. Unlike most instances of
Hiveclass does not have an
exit. Explain how and when
Bees leave the
armorattribute? What happens when
Problem 2 (2 pts). Add food costs and implement harvesters.
Currently, there is no cost for deploying any type of
Ant, and so
there is no challenge to the game. You'll notice that
out with a base
food_cost of 0. Override this value in each of the
subclasses listed below with the correct costs.
Now there's no way to gather more food! To fix this issue, implement the
HarvesterAnt class. A
HarvesterAnt is a type of
Ant that adds one food to the
Try playing the game again. Once you have placed a
HarvesterAnt, you should accumulate food each turn. Vanquishing
the bees using the default game setup is now possible, but should be
Problem 3 (2 pts). Add code to the
Place constructor that
tracks entrances. Right now, a
Place keeps track only of its
exit. We would like a
Place to keep track of its
entrance as well. A
Place needs to track only one
However, simply passing an entrance to a
Place constructor will
be problematic; we will need to have both the exit and the entrance before we
can create a
Place! (It's a chicken
or the egg problem.) To get around this problem, we will keep track of
entrances in the following way instead. The
should specify that:
Placealways starts with its
exit, then the
entranceis set to that
Problem A4 (2 pts). Add water to the colony. Currently there are only
two types of places, the
Hive and a basic
make things more interesting, we're going to create a new type of
Only an ant that is
watersafe can be deployed to a
Water place. In order to determine whether an
watersafe, add a new attribute to the
watersafe that is
False by default. Since bees
can fly, make their
overriding the default.
Now, implement the
add_insect method for
in addition to doing the same thing as a
Place would do,
immediately kills the added insect if it is not
armor. Do not copy and
paste code. Make use of inheritance to reuse the functionality of the
Once you've finished this problem, play a game that includes water. To access
mixed_layout that includes water, add the
-w for short) when you start the game.
python3 ants_gui.py --water
Problem A5 (3 pts). Implement the
FireAnt has a special
reduce_armor method that, when
FireAnt's armor reaches zero or lower, will reduce the armor of
Bees in the same
Place as the
3 (a fiery end indeed).
Hint: If you iterate over a list, but change the contents of that list at the same time, you may not see all the elements. As the Python tutorial suggests, "If you need to modify the list you are iterating over, you must iterate over a copy." Remember that damaging a bee may cause it to be removed from its place.
Once you've finished implementing the
FireAnt, give it an
implemented with the value
This attribute tells the game that you've added a new type of
FireAnt, be sure to test your program by
playing a game or two! A
FireAnt should destroy any co-located Bees
when it dies.
Problem B4 (2 pts). Implement the
nearest_bee method for
ThrowerAnt class. In order for a
attack, it must know which bee it should hit. The provided implementation will
only hit bees in the same
Place. Your job is to fix it so that a
throw_at the nearest bee in front of
it that is not still in the
nearest_bee method returns a random
the nearest place that contains bees. Places are inspected in order by
be able to
Bee in front of it that is not
still in the
Hive. Make sure that your ants do the right thing!
Problem B5 (3 pts).
Now that the
ThrowerAnt has been completed, implement two
Beethat is found after following at least 4
entrancetransitions. So the
Bees that are in the same
Placeas it or the first 3
Places in front of it.
Beethat is found after following at most 2
entrancetransitions. So the
ShortThrowercan only hit
Bees in the same
Placeas it and 2
Places in front of it.
Beethat is exactly 3
Places away. Placing a single one of these (and no other ants) should never win a default game.
To implement these behaviors, modify the
nearest_bee method to
max_range attributes, and only
return a bee that is in range.
For the base class,
min_range to 0
max_range to 10. Then, implement the subclasses
ShortThrower with appropriately
constrained ranges and correct food costs.
implemented class attribute of
Try playing a game with your newly implemented ants. Be sure that they do
what you expect them to! You can try running
ants_gui.py with the
--full option to go up against a full swarm of bees in a
multi-tunnel layout, and add
--insane if you want a real
challenge! If the bees are too numerous to vanquish, you might need to create
some new ants in Phase 2.
Problem A6 (1 pts). We are going to add some protection to our
AntColony by implementing the
is an ant that does nothing each turn (already the default
Ant class). A
WallAnt is useful because it has
Problem A7 (3 pts). Implement the
NinjaAnt, which damages
Bees that pass by, but is never seen.
NinjaAnt is not able to be attacked by a
because it is hidden, nor does it block the path of a
flies by. To implement this behavior, first modify the
to include a new class attribute
blocks_path that is
True by default. Set the value of
False in the
Second, modify the
blocked to return
False if either there is no
Ant in the
place or if there is an
blocks_path attribute is
Bees will just fly past
Finally, we want to make the
NinjaAnt damage all
Bee's that fly past. Implement the
action method in
NinjaAnt to reduce the armor of all
Bees in the same
place as the
NinjaAnt by 1, overriding the default
action method inherited from
For a challenge, try to win a default game using only
Problem B6 (1 pts). Currently there are no ants that can be placed on
Water. Implement the
ScubaThrower, which is a
ThrowerAnt that is more costly and
watersafe, but otherwise identical to its base class.
Water should not cause it to
Problem B7 (3 pts). We will now implement the new offensive unit
HungryAnt, which will eat a random
place, instantly killing the
Bee. After eating a
Bee, it must spend 3 turns digesting before eating again.
To implement, give
attribute that holds the number of turns that it takes all
HungryAnts to digest (default to 3). Also, give each
HungryAnt an instance attribute
digesting that counts
the number of turns it has left to digest (default is 0, since it hasn't eaten
anything at the beginning).
Now we implement the
action method of the
to check if it's digesting; if so, decrement its
Otherwise, eat a random
Bee in its
place (killing the
Bee and restarting the
Problem 8 (5 pts). Implement the
BushAnt. Right now, our
ants are quite frail. We'd like to provide a way to help them last longer
against the onslaught of the bees. Enter the
BushAnt differs from a normal
Ant because it can
occupy the same
Place as another ant. When a
is added to the same
Place as another ant, it shields the other ant
and protects it from damage. Attacks should damage the
first and only hurt the protected ant after the
BushAnt has an instance attribute
ant that stores
the ant contained within the bush. It should start off as
indicating that no ant is currently being protected. Give
contain_ant method that takes an
Ant argument and
ant instance attribute to that argument.
Now, change your program so that a
BushAnt and another
Ant can simultaneously occupy the same
Ant.containerclass attribute that indicates whether an ant can contain another. For all
BushAnt.containerattribute should be
Ants a new method,
can_contain, that takes an
otherant as an argument and returns
Trueif and only if:
add_insectmethod of the
Placeclass will immediately cause an error. Change
add_insectso that the
Placecontains the container ant and the container ant contains the other ant:
Antcurrently occupying this
Placecan contain the
Antwe are trying to add, then simply tell it to do so.
Antwe are trying to add can contain the
Antcurrently occupying this
Place, then have it do so and set this
Place's ant to be the newly added
Antcan contain the other, then raise the same assertion error as before.
Almost done! Just a few more things to do. When a
perishes, we need to make sure the ant it currently contains (if it contains
one) takes the
BushAnt's place. Override
reduce_armor method so that, if the
perishes, it will set its place's ant to be the ant it currently
contains. (Remember to use inheritance!)
The last step is to make sure that ants that are contained
BushAnts still perform their action. Override
action method for
Problem 9 (4 pts). Implement two final thrower ants that do no damage,
but instead replace the
action method of a
instance that they
throw_at with a new method that alters the
Bee's behavior for some duration. You will do this by writing the
apply_effect function, which takes a
Bee instance and
changes its action method.
Bee's original action on even-numbered turns (
colony.time % 2 == 0). A stun action will cause the
Beeto do nothing. Both of these affected methods can be created by higher-order functions that take and return an action method. You will find
Status Effectsection of
Implement two new ants that subclass
ThrowerAnt. You only need
to set their class attributes appropriately.
SlowThrowerapplies a slow effect for 3 turns.
StunThrowerapplies a stun effect for 1 turn.
You are now done with the project!. If you weren't able to vanquish the bees' insane-mode assault plan before, do your new ants help? Add some water or design your own layout to keep things interesting.
Feel free to design additional ants, layouts, and assault plans and post them to Piazza.
Acknowledgements: Tom Magrino and Eric Tzeng developed this project with John DeNero. Jessica Wan contributed the artwork.