The Snake

Created with C++14 and QT 5.13.2

Description

Player can set the initial speed and snake length before starting the game. Controll the snake with arrow keys. Enjoy the game.

Game class

Once initialized, the menu window appears and asks for input. No input means using hardcoded values. Game starts when Start Game button is hit.

Fields

Variable	Description
`Board* board`	The Board class
`Menu* menu`	The Menu class

Methods

Method signature	Description
`startGame()`	Close the menu, initialize the Board.
`quitGame()`	Close the application.

Menu class

Prompts the player for input. Passes the input for the Board class.

Fields

Variable	Description
`Ui::Menu ui`	Menu window which appears when staring the app
`int time`	Containts the game time from input
`int snakeLength`	Containts the snake length from input

Methods

Method signature	Description
`void setLength(int)`	`snakeLength` setter
`int getLength() const`	`snakeLength` getter
`void setTime(int)`	`time` setter
`int getTime() const`	`time` getter

Slots

Slot signature	Description
`void on_startGameButton_clicked()`	Gathers input from text windows and emits `startGame()` signal
`void on_quitGameButton_clicked()`	Emits `quitGame()` signal

Signals

Signal signature	Description
`void startGame() const`	Received by Game's `startGame()` slot
`void quitGame() const`	Received by Game `quitGame()` slot

Controller class

Controlls the timers which make the snake move and fruit appear.

Variable gameTimer contains game elapsed time.
When needed, the Controller object stops or restarts the game.
When the game ends the object gives the player total score and prompts to play again or quit.

Fields

Variable	Description
`QGraphicsScene* gameScene`	Scene displaying game objects
`Snake* snake`	Snake pointer
`QTimer* snakeTimer`	Moves the snake with `Data::snakeLatencySpeed` `QTimer* fruitTimer`
`QElapsedTimer* gameTimer`	Counts elapsed time.
`int gameTime`	Used when starting a new game
`int snakeLength`	Used in Snake constructor and when starting a new game
`static int score`	Player's score
`static int fruitsNumber`	Containts the current number of fruits in the `gameScene`

Methods

Method signature	Description
`Controller(QGraphicsScene, QObject, int, int)	Initializes the timers and the snake
`void startTimers() const`	Starts the timers
`void stopTimers() const`	Stops the timer
`void restartGame()`	Start timers and reinitialize `snake`, set `score` and `fruitsNumber` to 0
`void stopGame()`	Calls `stopTimers()` and ask the player to play again or quit.
`void quitGame() const`	Closes the app
`QString gameEndMessage() const`	Shows the total score multiplied by 10
`void keyPressEvent(QKeyEvent*)`	Reads key input from the player
`bool eventFilter(QObject, QEvent event) override`	Calls `keyPressEvent(event)`
`bool checkFruitsNumber() const`	Returns true if `fruitsNumber` is greater or equal than `Data::maxFruitNumber`
`void CheckCollisions()`	Call all the checking methods below
`bool checkWallCollision() const`	Returns true whenever `snake` hits a wall(window border)
`bool checkSnakeCollision() const`	Returns true if `snake` eats itself
`void checkItemCollision() const`	Checks if snake`snake`'s eaten a fruit

Slots

Slot signature	Description
`void spawnFruit()`	Spawns a fruit if `checkFruitsNumber()` return false
`void moveSnake()`	If elapsed time is less than `gameTime`, `snake` is moved

Snake class

Snake is a moving set of points. Its shape is a set of circles painted on the points coordinates. The biggest circle is the head. The snake grows when a fruit is eaten. Is controlled with arrow keys, can move in any direction except diagonal. Inherits from QGraphicsItem.

Fields

Variable	Description
`QPointF head`	Point containing coordinates of snake's head
`QVector<QPointF> tail`	Vector containing the coordinates of the tail points
`QGraphicsScene* scene`	Pointer to `Board`'s `scene`. Used to remove eaten fruits from `scene`
`Data::Direction direction`	Enum containing info about the direction snake's heading to. Initial `direction` is set to `Data::Direction::Right`
`int velocity`	Current snake's speed
`int xDirection`	How far can snake go in left or right, set by `velocity`. Initialized with `Data::velocity`
`int yDirection`	How far can snake go in up or down, set by `velocity`. Initialized with 0
`int snakeLength`	Snake's length
`int toGrow`	How many `QPointF` coordinates to add to `tail`

Methods

Method signature	Description
`Snake(QGraphicsScene* gameScene, int snakeLength)`	Set `head` coordinates to the middle of the `gameScene`
`QPainterPath shape() const`	Sets snake's shape to a set of circles based on `head` and `tail` points
`QRectF boundingRect() const`	Sets a rectangular shape to the body.
`void paint()`	Paints the shape
`void move()`	Updates `head` and `tail` positions
`bool wallHit()`	Returns true if `head` coordinates met a frame of `scene`
`void goThroughWall()`	Checks which wall was hit by `head` and makes it appear on the opposite side of the `scene`
`void eatFruit()`	Removes the eaten fruit, increases `Controller::score`, makes the snake grow
`void checkCollision()`	Eats a fruit if any was hit by `head`
`void moveLeft()`	Sets `xDirection` to `-velocity` and `yDirection` to `0`. Thus `direciton` is set to `Data::Direction::Left`
`void moveRight()`	Sets `xDirection` to `velocity` and `yDirection` to `0`. Thus `direciton` is set to `Data::Direction::Right`
`void moveUp()`	Sets `xDirection` to `0` and `yDirection` to `-velocity`. Thus `direciton` is set to `Data::Direction::Up`
`void moveDown()`	Sets `xDirection` to `0` and `yDirection` to `velocity`. Thus `direciton` is set to `Data::Direction::Down`
`bool intersects() const`	When `tail` contains `head` it means that snake's eaten itself. Returns true so
`void updateHead()`	Sets `head.x()` to `head.x() + xDirection` and `head.y()` to `head.y() + yDirection`
`void updateTail()`	Adds a new `QPointF` to `tail`.

Board class

Board is responsible for displaying snake, its movement, and furit. Inherits from QGraphicsView.

Fields

Variable	Description
`QGraphicsScene* scene`	Surface to manage 2D objects
`Controller* controller`	Initialized at the same time as the Board

Methods

Method signature	Description
`Board(int, int)`	Initializes `controller` and `scene`, sets the background

Fruit class

A 2D object inheriting from QGraphicsItem. When eaten, enlengthens the snake.

Methods

Method signature	Description
`Fruit(qreal, qreal)`	Sets the coordinates to given `qreal` variables
`QPainterPath shape() const`	Sets shape to circle
`QRectF boundingRect() const`	Sets `Fruit`'s boundary to a rectangle
`void paint(QPainter, const QStyleOptionGraphicsItem, QWidget*)`	Paints the shape

MateuszW99/Snake

The Snake

Created with C++14 and QT 5.13.2

Description

Game class

Fields

Methods

Menu class

Fields

Methods

Slots

Signals

Controller class

Fields

Methods

Slots

Snake class

Fields

Methods

Board class

Fields

Methods

Fruit class

Methods

Contants.h

Contains all the game's constans used in the code.