VG101RECITATION 8By TAs

CONTENTS

Brief review of class Strategy for assignment 9 Questions about assignment 7, 8

BRIEF REVIEW OF CLASS

In header file: Base class Constructors Private/protected/public member Data/ function member Accessors/ Mutators

In cpp file: Implementation of class functions

class RectangleT : public GObjectT{

PointT llp, urp;void drawRect ();

public:RectangleT (const double x0 = 0, const double y0 = 0,

const double x1 = 0, const double y1 = 0, const string clr = "Blue", const double fill = 0);

RectangleT (const PointT &p0, const PointT &p1, const string clr = "Blue", const double fill = 0);

const PointT &getLocation () {return llp;}double getWidth () const;double getHeight () const;double getArea () const;void setLocation (const double x, const double y);void setLocation (const PointT p);void setWidth (const double w);void setHeight (const double h);void draw ();void draw (const string clr, const double density = 0);

};

Base class

Private membe

r

Public membe

r

constructor

Get & Set

Data members

Function members

BRIEF REVIEW OF CLASS

Base class Base class will be constructed first // BallT is a derived class from ArcT // A ball is an arc of 360 degree BallT (double r = 0) : ArcT (r, 0, 360, "Blue", 1)

{};

Constructors Always define a default constructor (suggested) One and only one of the constructors must be

called

STRATEGY FOR ASSIGNMENT 9

Divide the project into several stages: 1. class design 2. initialization 3. get ball/paddle moving 4. handle collisions 5. end of game

One function for one simple purpose only Test your functions one by one Test your program after finishing each stage Have fun after finishing the whole project

STAGE ONE: CLASS DESIGN

Game window: GwindowT Represent the application window

Brick wall Represent all the bricks Row, column, vector of bricks…

Brick: RectangleT Represent one brick Color, position(row, column), location( x, y)…

Paddle: RectangleT Location(x, y) …

STAGE ONE: CLASS DESIGN

What need you to design: 1. constructors 2. data members and their accessors and mutators 3. special functions: Samples:

// let the paddle move when being selectedbool paddle::selected(…)void paddle::move(…)

// draw the brick wall, the main function in initialization

void brickWall::draw(…)

STAGE TWO: INITIALIZATION

Initialize the game: 1. init brick wall, give color, location to each

brick 2. init paddle, give color, location to it 3. draw the window ,the wall and paddle

No movement in this stage Refer to the lecture note on drawing the brick

wall

STAGE THREE: GET BALL/PADDLE MOVING

To move the ball Just as what you do in assignment 5-2 Consider the brick wall as a static border of the

window, don’t drop out the brick been clicked

To move the paddle Just as the movingBall program discussed in

lecture (page 46) Don’t let the paddle move out of the window

These are not difficult, but they are basis for the following stage

STAGE FOUR: HANDLE COLLISIONS

Three kinds of collision 1. ball and brick 2. ball and paddle 3. ball and window

For kind 2 and 3, it’s similar to assignment5-2

Refer to the boundary check discussed in lecture (page 27)

Remember to check the position of the paddle to see whether the ball falls onto the paddle or falls out.

STAGE FOUR: HANDLE COLLISIONS

For kind 1, divide it into two steps 1. how to determine whether a known brick

collides with the ball? 2. search among all the existing brick in the wall

to find the brick to be clicked Maybe you need a function

bool BrickT::isClicked(…) 3. do changes to the ball (direction), and do

changes to the brick (disappear)

You just need a for/while loop to do the searching and a if statement to handle the collision

STAGE FIVE: END OF GAME

Taking care of some small details in the game: You’ve got to take care of the case when the ball

hits the bottom wall You need to check for the other terminating

condition, which is hitting the last brick You should experiment with the settings that

control the speed of your program Most importantly, you’ve got to test your

program to see that it works

QUESTIONS ABOUT ASSIGNMENT 7, 8

Send your code to TA’s email box if you didn’t submit your assignment before deadline

Any questions?