A Group Project Report on

ROAD ATTACK

Submitted to The Department of Electronics and Computer Engineering

In partial fulfillment of the academic requirements ofSNIST

ForThe award of the degree of

Bachelor of TechnologyIn

Electronic and Computer Engineering (2010 – 2014)

ByT samba siva rao 11315A1919B sandeep kumar 11315A1921P rakesh kumar 11315A1922

Under the Guidance ofShayam babu

Sreenidhi Institute of Science and Technology(AUTONOMOUS)

Yamnampet, Ghatkesar, R.R. District, Hyderabad - 501301

Department of Electronics And Computer Engineering

Sreenidhi Institute of Science and Technology

CERTIFICATE

This is to certify that this project report on

“EXTREME RACING”, submitted by T.sambasiva(11315A1919), B.sandeep

(11315A1921),P.rakesh(11315A1922) in the year 2012 in partial fulfillment of the

academic requirements of Sreenidhi Institute of Science and Technology for the

award of the degree of Bachelor of Technology in Electronics and Computer

Engineering, is a bonafide work that has been carried out by them as part of their

Group Project during Third Year First Semester, under our guidance. This

report has not been submitted to any other institute or university for the award of

any degree.

M.Shyam babu K.SASIDHARAssistant Professor Department of ECM HOD Internal Guide Department of ECM

ACKNOWLEDGEMENT

This project report is the outcome of the efforts of many people, who have driven my

passion to explore into Java. We have received great guidance, encouragement and support from

them and have learned a lot because of their willingness to share their knowledge and

experience.

Primarily, we should express our deepest sense of gratitude to our internal guide

Mr.M.shyam babu, Assistant Professor, Department of ECM. His guidance has been of immense

help in surmounting various hurdles along the path of our goal.

We are deeply indebted to Mrs. Sasidhar .K, Head, and Department of ECM, who spared

her most valuable time without any hesitation whenever we wanted.

We record with a great feeling of gratitude, the contributions of all the faculty members,

who encouraged us during this project by rendering their help when needed.

Finally we thank our parents and adore Almighty God who has made us come in contact

with such worthy people at the right time, provided us with all the necessary resources and made

us accomplish this task.

T. samba siva P.rakesh kumar

B. sandeep kumar

INDEX

Abstract i

List of Figures ii

1. INTRODUCTION 1

1.1 Project Specification 2

2. SYSTEM DESIGN 4

2.1 Modules 4

3. SYSTEM IMPLEMENTATION 07

4. TEST 20

5. CONCLUSION 37

6. REFERENCE 38

ABSTRACT

The main objective of this project is to develop a Java based personal computer game.

Basically it’s a car racing game in which user’s car has to reach the destination in the given time

by avoiding the obstacles. If user completes one level successfully, he will be forwarded to next

level with increased complexity.

User can change his car, save his score and enable or disable back ground sounds. User

can use special features like Health, Time and Speed booster in reaching the destination.

1

1. INTRODUCTION

About Game:

Extreme Racing is a JAVA based PC game where the user’s car has to reach the destination

within a given time avoiding the Obstacles. There will be maximum ten levels. User has to cross

ten levels to win the game. User will be provided with 4 lives to complete the game. In addition,

he can use additional features like weapons to fire the enemies and special features like boosters

to reach the destination.

JAVA:

Java is a Programming Language and computing platform first released by Sun Microsystems in

1995.It is the underlying technology that powers state-of-art technology including utilities,

games and applications.

It was started in 1991 as a project named “Green”, to develop a platform-independent language

that can be used to create software to be embedded in various consumer electronic devices, such

as microwave ovens and remote controls etc.

Java runs inside a piece of software known as a Java Virtual Machine.

In many languages, such as C and C++, the source code (.c and .cpp files) is portable.

What makes Java unique is that Java’s executable code is also portable (.class files).

This means that the same application can be run without modification on any system that

has a Java Virtual Machine without being recompiled.

2

1.1 Project Specifications:

Software Requirements:

1. Java SE 1.6

2. Any OS that supports java

Hardware Requirements:

A personal computer with

1. Processor – PIV or above

2. RAM – Minimum of 512

3

2. System Design

2.1 Modules

There are 5 Panels in this project. They are

1. Start Screen

2. Game Panel

3. Options

4. High Scores

5. Help Panel

4

2.2.1 Use case Diagram:

Figure 2.1 : Use case Diagram

5

2.2.2 Class Diagram:

Figure 2.2 : Class Diagram

6

2.2.3 Sequence Diagram:

Figure 2.3: Sequence Diagram

7

2.2.4 Collaboration Diagram:

Figure 2.4: Collaboration diagram

8

2.1.1 START SCREEN:

Start Screen is the interface between the user and the game. It allows the user to select the

options of his own. It is the first screen that appears when a user opens the game. It provides user

interface components to start the game, to view the high scores, to exit from the application,

game options etc. Depending on the user input in this screen, user will be taken further in to the

game.

Start screen includes features like

Start game: Takes user in to the Game

Options :Gives Options like Select Car and background music

High Score : Displays the High Scores of the previous users

Help : Shows the game controls and special features.

Exit : Exit the game.

2.1.2 Game Panel

When the user clicks on start game button in start screen, he will be brought to this screen. This

is the Panel where the user plays the game. This panel contains some components on either sides

to display information about the game.

Components that appear on Game Panel:

Score – displays the score of the user

Level – Shows the current level.

Lives – Shows number of lives left

Time – Shows time left to reach the destination.

9

2.1.3 Options Panel

This is the panel where the user can select options of his choice. This panel allows the user to

select car and change the sounds on/off.

Components that appear on Option Panel:

Select Car-Allows user to select the car.

Sound-Allows the users to set sounds on/off.

2.1.4 High Scores

This panel displays the High Scores to the User. When the user finishes the game he will

prompted to enter user’s name to stores his score.

This window can be focused in two ways:

When the User click on High Scores button on Start Screen.

When the user finished the game, he will be directed to High Scores Panel.

2.1.5 Help Panel

This panel displays help information for user.

Help Screen include:

Direction Keys-It tells the keys to be used in directing the car

Special Features-It tells about special features in the game like Bullets, Pause, Main

Menu, Boosters.

10

3. System Implementation

3.1 Game Window:

This class extends JFrame. JFrame creates a window. This is the only window in the project. All

the panels in the game are added to this window and switched according to the user input.

Creation of multiple objects is avoided by using the concept ‘singleton object’. Card layout is

used to set the layout of the main frame. Panels are switched based upon the user input.

Sample code for creating singleton object:

publicstaticGamePanelgetGamePanel(){

if(gamepanel == null)gamepanel = newGamePanel();

returngamepanel;}

3.2 Start Screen:

This class extends a Jpanel. Jpanel is a plain surface that can be added to frames. An object for

this screen is created and added to the main frame (Game window). This panel contains 5 buttons

start game, options, high score, help, exit. When user clicks on a specific button we switch the

panel in the cardlayout (maincardlayout). Several images will be displayed in this screen.

Following is the sample code for loading images into the project.

Sample code for creating image:

ImageIconstarticon = newImageIcon(this.getClass().getRe-source("startgame.jpg"));

startimage = starticon.getImage();

11

getContentPane() method returns the object of the default panel on game window. By using this

method, an object of default panel is created and other panels are added to it.

sample code for adding panel to cardlayout

startScreen = newStartScreen();getContentPane().add(startScreen,"start screen");

Sample code for switching panels

GameWindow.getGameWindowInstance().changePanel(GameWindow.getContentPane(),”game panel”);

3.3 Game Panel

3.3.1 Timer Class

Creates a Timer and initializes both the initial delay and between-event delay to

delaymilliseconds. If delay is less than or equal to zero, the timer fires as soon as it is started. If

listener is not null, it's registered as an action listener on the timer.

Fires one or more action events after a specified delay. For example, an animation object can use

a Timer as the trigger for drawing its frames.

Setting up a timer involves creating a Timer object, registering one or more action listeners on it,

and starting the timer using the start method. For example, the following code creates and

starts a timer that fires an action event once per second (as specified by the first argument to the

Timer constructor). The second argument to the Timer constructor specifies a listener to receive

the timer's action events.

Sample code

int delay = 10; //millisecondsTimer timer = new Timer(delay,this);

12

timer.start();

3.3.2 Paint Method

Invoked by Swing to draw components. This method actually paints all the images in our game.

Applications should not invoke paint directly, but should instead use the repaint method to

schedule the component for redrawing.

Sample code

publicvoid paint(Graphics g){

super.paint(g);g.drawImage(roadimage, road_x, road_y[0], this);g.drawImage(roadimage, road_x, road_y[1], this);

}

3.3.3 ActionPerformed method

This method many actions in our game such as calculating the score, levels, lives, distance,

changing the position of the road, changing position of the enemy cars, changing positions of the

bullets etc. All these are maintained in different methods. This method gets called every time the

timer object raises the event.

Sample code

public void actionPerformed(ActionEvent e)

{

accelerate();moveRoad();moveBullets();moveEnemies();checkCollision();

}

3.3.4 Moving road

Timer object fires the event for every 10 milli seconds i.e paint method, actionPerformed method

gets called 100 times for every second. The position of the images is changed in actionPerformed

method. Beacause of changing positions of the images and repainting, user gets illusion that the

car is moving. The position of the road is changed in actionperformed method.

13

Sample code for changing position of the road.

road_y[1]+=acceleration;if(road_y[1]>=(810-acceleration))

road_y[1] = 0;

road_y[0] = road_y[1]-810;

When the road crosses the position of 810, it’s position has been changed to 0. An another road

image in road[0] position will always follow the road in road[1] position. So the road images will

be moved in a continuous loop.

3.3.5 Acceleration of user’s car

Acceleration of the user car is maintained by using a variable called acceleration. As long as the

user presses the up arrow key, this variable gets incremented. Acceleration decrement is

constantly maintained by decrementing the acceleration variable when the user does nor presses

the up arrow key.

Sample code of maintaining acceleration

if(upkeypressed){if(acceleration<max_acceleration){

acceleration++;}}

14

3.3.6 Moving bullets

Two arrays are created to maintain the x and y positions of the bullets. When the user presses the

button ‘x’ the positions(x,y) of one bullet is initialized. As long as user presses the x button, the

x,y positions of bullets are initialized. These positions are moved by changing these positions in

actionperformed method. When a bullet crosses the border, it will be initialized to zero. Bullets

are painted in paint method when their positions are not zero.

Sample code

PrivatevoidmoveBullets() {

for(int i = 0;i<bullet_y.length;i++){

if(bullet_y[i] != 0)bullet_y[i]-=10;

if(bullet_y[i] < 0)bullet_y[i] = 0;

} }

3.3.7 Moving enemies

Enemy car’s y position is changed every time action performed method gets called. When the

enemy car crosses the border, it’sy position is initialized to a value less than zero so that it comes

from the starting position again. It’s x position is relocated by using locateEnemyPosition

method. Enemy car is moved with a value greater than user car’s acceleration so that if the user

car moves fast, enemy car also moves fast.

Sample code

PublicvoidmoveEnemies(){

enemy_y+=(acceleration+4);if(enemy_y>810){

enemy_y = -200;locateEnemyPosition();}}

15

3.3.8 Checking collision

Enemy car’s collision with user car is maintained in the checkcollision method. This method is

called in actionperformed method. Each time enemy car’s position is changed, it’s collision with

the user’s car is checked. If enemy car hits the user car 4 times, a variable called lives is

decremented. When this variable comes to zero, the game is ended and user is prompted to save

his score.

Sample code

publicvoidcheckCollision(){

if((enemy_y+85)>=car_y&&enemy_x>=(car_x-45) &&enemy_x<=(car_x+45)){enemy_y = -200;locateEnemyPosition();energy-=100;if(energy == 0){

energy = 400;lives--;lifeover = true;if(lives == 0)

gameover = true;}

}}3.3.9 Playing Audio

User can enable or disable sounds from the options screen. Audio is played by using the classes

AudioSystem, Clip. Audio files are loaded and played in GamePanel class.

Sample code for loading audio files into the project

publicvoid initAudioFiles(){

try{File file = new File("sound.wav");

audioIn = AudioSystem.getAudioInputStream(file);

// Get a sound clip resource.mainaudioclip = AudioSystem.getClip();audioIn2 = AudioSystem.getAudioInputStream(file2);bulletclip = AudioSystem.getClip();audioIn3 = AudioSystem.getAudioInputStream(file3);explosionclip = AudioSystem.getClip();

// Open audio clip and load samples from the audio input stream.

16

mainaudioclip.open(audioIn);// Open an audio input stream.}catch(Exception e){}

}

Sample code for starting an audio clip

mainaudioclip.start();mainaudioclip.loop(mainaudioclip.LOOP_CONTINUOUSLY);

3.3.10 Reading User Settings

User settings saved in highscores.txt are read by using the method getUserSettings().

Sample code for reading user settings

publicvoid getUserSettings(){

try{File f; f=new File("settings.txt");if(!f.exists()){ f.createNewFile();usercar = "usercar2.jpg";sounds = false;return; }else{ FileInputStream fstream = new FileInputStream(f); DataInputStream in = new DataInputStream(fstream);

BufferedReader br = new BufferedReader(new InputStreamReader(in)); String line; String[] all = new String[3];while((line=br.readLine())!=null) {

all = line.split(","); }if(all[0]!=null)usercar = all[0];else

usercar = "usercar2.jpg";if(all[1].equals("on"))

sounds = true;else

sounds = false; }

}catch (Exception e) {// TODO: handle exception

17

}}

3.3.11 Keyboard input

KeyAdapter class is used to take input from the user in this game. Java language rules are such

that we must implement all the methods of an interface even if we can put them into empty

braces i.e we must override all the methods declared in the interface.

But we can create our classes as subclasses of one of the adapter classes then we need to override

only some of the methods we need. An adapter calss provides an empty implementationof all

methods declared in listener concerned interface.

Keypressed(KeyEventke) method is used to identify which key has been pressed.

Ke.getkeycode() method returns the Unicode of the character. When a key is pressed, it will be

checked with getkeycode() method and the corresponding action will be performed.

3.3.12 The KeyEvent Class

IntgetKeyChar( ) which returns the character that was entered, and intgetKeyCode( ) which

returns the key code.

It defines many integer constants:

VK_ENTER VK_ESCAPE VK_CANCEL VK_UP

VK_DOWN VK_LEFT VK_RIGHT VK_PAGE_DOWN VK_PAGE_UP

VK_SHIFT VK_ALT VK_CONTROL

18

3.4 High Scores Screen

User high scores are saved using text file. A text file is created through the code and user’s high

scores are saved in it. When the user opens the game, the list of high scores are loaded into the

game. Every time, when user completes the game, he is prompted to save his score.

This score is checked with the list of high scores and will be saved if it is better than top 10th

high score in the list.

Sample code for creating new text fileFile f;

f=newFile("HighScore.txt");if(!f.exists()){f.createNewFile(); }

Sample code for reading file contents.

FileInputStreamfstream = newFileInputStream(f);DataInputStream in = newDataInputStream(fstream);BufferedReaderbr = newBufferedReader(newInputStreamReader(in)); String line;String[] all = new String[3];

while((line=br.readLine())!=null) {

all = line.split(",");al.add((Object)all);

}

Sample code for writing file contents.

fwriter = newFileWriter(f);

BufferedWriter br2 = newBufferedWriter(fwriter);for(int i = 0;i<al.size();i++) {

String[] p = (String[])al.get(i);br2.write(p[0]+","+p[1]+","+p[2]+"\n");

}br2.close();

19

3.5 Options Screen

User’s setting are also saved in a text file. Buffered reader and buffered writer classes are used to

save settings into the text file. Two settings(usercarimage,sounds) are saved in the file. User

settings are loaded into the game when user opens the game for the first time.

Sample code for saving settings

publicvoidsaveSettings(){FileWriterfwriter = newFileWriter(f);

BufferedWriter br2 = newBufferedWriter(fwriter);br2.write(selectedcar+","+sound+"\n");br2.close();

}Sample code for reading user settings

while((line=br.readLine())!=null)all = line.split(",");

selectedcar = all[0] ;sound = all[1];

if(selectedcar.equals("usercar1.jpg"))carnum = 1;

elseif(selectedcar.equals("usercar2.jpg"))carnum = 2;

3.6 Help Screen

All the help information for the user is painted in the paint method. A user interface component

is placed in the screen for the user to go to the main menu.

20

Sample code for displaying help information

publicvoid paint(Graphics g) {// TODO Auto-generated method stubsuper.paint(g);

g.setFont(bigfont);g.setColor(Color.red);g.drawString("Help", 300, 50);

g.setColor(Color.yellow);g.setFont(mediumfont);

g.drawString("DIRECTION KEYS", 20, 100);g.setFont(smallfont);g.setColor(Color.red);

g.drawString("UP ARROW ",20,150);g.drawString("DOWNN ARROW ",20,200);g.drawString("LEFT ARROW ",20,250);g.drawString("RIGHT ARROW ",20,300);

}

Testing:

When the user clicks on any of the buttons available, he will be directed to a new screen. Based on the user actions, he will be proceeded further in the game.

21

When the user clicks on Start Game button he will be redirected to new window in which the user can play the game. In this user can find many features like

1. Level2. Score3. Time4. Lives left5. Health6. Accelerometer7. And a small window showing position of car in the main track.

22

As shown in the figure, Level indicates the current level the user is playing. It shows 1 when the game is started indicating that the user is in 1st level of the game. When the user completes the first level, the value of Level tab will become 2.That is each time when the user completes a level value of level tab will be automatically incremented by 1.There are maximum of ten levels in the game.

When the user finishes the level, to indicate the end of the level Finish line will be displayed.

23

When the user finishes all the levels successfully, a message will be displayed congratulating the winner.

24

Another important feature in this game is the Score tab. When the user starts the game initial score of the user is zero. As the user proceeds in the game he will be awarded the score according to the distance he race through. Score will be awarded for the distance he travel. There

25

is a maximum of 3000 meters track in the game, when the user finishes the level he will have the score of 3000. In addition to the score awarded based on distance he travel, additional scores will be awarded when the user attacks the opponent cars with the provided bullets. User can fire bullets by pressing “X” key in key board. Each time user attacks the opponent he will be awarded the bonus of 100 points. The more user attacks the opponents more he gets bonus and more score.

As shown in the above figure, Score increased to 8001 and level changed to 2 indicating that the user is now in 2nd level. Also, the figure shows the bullets released by the user when he is attacking the opponents. Each time bullet hits the opponent, user gets a bonus of 100 points.Anytime, user can be redirected to Start Screen by pressing “M” key in the key board.

Time indicates the time left for the user to reach the destination. User will be given a time of 60 seconds to reach the destination. If he failed to do so he will lose the game. If he reaches the destination within the given 60 seconds he will be promoted to next level.

26

Health of the user is indicated by a special bar at the bottom of the screen. Initially user has full health. Each time user collides with an obstacle, health will be reduced by 25%. When user collides with obstacles for 4 times, user’s car will explode and user will lose one of his lives and the level will restarted.

As shown in the above figures, Lives of the user are denoted by the special symbol in the window below the time tab. Each time user’s health reduced to zero one out of four lives will be reduced.

27

When user loses all his four lives he can no longer continue with the game. He will be asked to save his score in the High Scores window and exit the game.

User will be redirected to High Scores window. In High Scores window a new text field and button named “ok” will be displayed allowing the user to register his name to save his score.

If the users score stands in top 10 scores it will be displayed in the top scores list with serial name indicating position he is standing, name of the user and his score.

Name of the user should not include special characters. It should be a plain text. If the user enters any wrong details he will be prompted with a warning dialog box and will be asked to enter correct details.

28

When the user clicks on Main menu button in the High Scores tab he will be redirected to Start Screen window.

Accelerometer on the right side of the main track indicates the speed at which car is moving. The maximum speed of the car is 156.

Small track with a small car to the right of the main track indicates the position of the car in the track. It gives an idea to the user about the distance left to reach the destination so that the user can speed up or slow down to reach the destination in given time.

During the race when the users proceed special features like health, speed and time booster will arise along the track. When user takes this booster, respective powers will be activated.There are 3 types of boosters.

1. Health

29

2. Speed3. Time

When the user gets the Health Booster, health of the user will be increased to maximum. This feature helps the user to increase the health when the health is going down. It helps the user in reaching the destination with less chance of losing the life.

When user gets the Speed booster, speed of the user will be incremented. Initially user has a maximum speed of 156. But, when the user takes the Speed Booster speed will be increased to 220. This feature helps the user to reach the destination with more speed and thereby saves the time of the user.

30

This speed added by this feature stands until the end of the level.

31

When the user gets the Time Booster, it will add additional time of 20 seconds to the user. This feature helps the user when he is running short of time. So that user can reach the destination with the help of this additional time.

These 3 boosters Health, Speed and Time will rise randomly in the track.

When the User clicks on Option Button in the Start Screen, he will be redirected to Options window. In the Option window user can select car of his choice and also user can set sounds On or Off.

32

In Select car tab, user will be provided with 4 different types of cars. User can select one of the four cars.

In Sounds tab, user can set the game sounds On/Off with the help of the radio buttons provided

When the user clicks on the Main menu tab in Option window he will be redirected to Start Screen of the game.

33

After making the required changes user have to save the changes. He can do so by clicking on save button to save changes. When user clicks on save button, a new dialog will be displayed prompting the user that the settings are saved.

When the user clicks on Ok button in dialog box he will be redirected to Start Screen Window to continue with the game. Now the when the user starts the game selected car will be used in the game and sound changes also will be effective.

34

When user clicks on High Scores button in the Start Screen, he will be redirected to High Scores window. High Scores window displays logs of high scores recorded in the game.

High Scores window displays the high scores of the users in descending order. That is top scores stands first in the position of rankings.

High Scores window can display the records of 10 users. When a new record is created it will be recorded into the log based on the score and least score will be taken out from the high scores log.

35

When the user clicks on Help button in the Start Screen window, he will be redirected to Help Window. Help contains information needed for the user to play the game.

Help Contains information about 1. Direction Keys2. Special features.

Direction Keys helps the user in controlling the car.1. UP Arrow – Move forward2. DOWN Arrow – Apply breaks3. Left Arrow – Move left4. Right Arrow – Move right

36

Special Features contains information about special buttons and booster icons.

1. X : To fire Bullets2. P : To pause the game3. M : To display main menu

And also contains information needed to identify the boosters.

To exit from the game user can click the Exit button in Start Screen window. When the user clicks on the exit button he will be directed out of the game.

37

5. Conclusion

Practical Training is very important part of the curriculum as it strengthens the concepts and

enhances knowledge about the practical implementation of all theory concepts, we have learnt so

far in different subjects.

In future we can enhance this “Extreme Racing Game” using new technologies because its codes

are so simple that a lay man can understand. Since this is developed in java which is truly object

oriented language it support the future additions and eliminations in the code. We can increase

the flexibility with adding new levels to the game and new items in the appearance of the game.

Although we have completed this project, due to lack of knowledge on a few concepts and

constraint of time, we could not include some more features we wanted to. We left these features

as a part of the future development.

38

6. References

• The java Language specification, third edition by James Gosling, Bill Joy, Guy

Steele, Gilad Bracha.

• Introduction to Programming using java, sixth edition by David J Eck

• http://www.mybringback.com/tutorials/

• http://www.tutorialspoint.com/

• http://www.java2s.com/Tutorial/Java/CatalogJava.html

39