Files
eceg431/09/Snake/SnakeGame.jack
2025-11-14 15:23:07 -05:00

287 lines
8.3 KiB
Plaintext

// Main game controller for Snake
// Handles input, game loop, scoring, and game state management
class SnakeGame {
field Snake snake;
field Food food;
field int score;
field boolean gameOver;
field boolean paused;
field int speed;
field char lastKey;
field int pendingDirection;
field boolean restarting;
// create new snake game
constructor SnakeGame new() {
let snake = Snake.new();
let food = Food.new();
do food.spawn(); // spawn food at random position
let score = 0;
let gameOver = false;
let paused = false;
let speed = 150; // milliseconds between moves
let lastKey = 0;
let pendingDirection = 0;
let restarting = false;
do Random.seed(123); // initialize random generator
do drawUI();
return this;
}
// free memory
method void dispose() {
do snake.dispose();
do food.dispose();
do Memory.deAlloc(this);
return;
}
// draw game interface elements
method void drawUI() {
// draw header area with border only on third row
do Screen.setColor(true);
do Screen.drawRectangle(0, 22, 511, 32); // border only on third row
do Screen.drawRectangle(0, 248, 511, 255); // bottom border
do Screen.drawRectangle(0, 32, 7, 255); // left border (starts below header)
do Screen.drawRectangle(504, 32, 511, 255); // right border (starts below header)
do showGameTitle();
do showScore();
do showControls();
return;
}
// display game title
method void showGameTitle() {
do Output.moveCursor(0, 0);
do Output.printString("SNAKE GAME");
return;
}
// display current score
method void showScore() {
do Output.moveCursor(1, 0);
do Output.printString("Score: ");
do Output.printInt(score);
return;
}
// display game controls
method void showControls() {
do Output.moveCursor(0, 35);
do Output.printString("Arrows: Move Space: Pause");
do Output.moveCursor(1, 35);
do Output.printString("Enter: 2x Speed R: Restart");
return;
}
// display game over message
method void showGameOver() {
// draw larger border box (centered on screen)
do Screen.setColor(true);
do Screen.drawRectangle(100, 80, 412, 180); // outer border
do Screen.setColor(false);
do Screen.drawRectangle(102, 82, 410, 178); // inner area
// properly centered text
// Box spans columns 12-51 (39 chars wide), center at column 31
do Output.moveCursor(10, 26); // "GAME OVER!" (10 chars) centered at 31-5=26
do Output.printString("GAME OVER!");
do Output.moveCursor(12, 23); // "Final Score: XXX" (~16 chars) centered at 31-8=23
do Output.printString("Final Score: ");
do Output.printInt(score);
do Output.moveCursor(14, 15); // "Press R to restart or Q to quit" (32 chars) at 31-16=15
do Output.printString("Press R to restart or Q to quit");
return;
}
// handle user input with key press detection
method void processInput() {
var char key;
let key = Keyboard.keyPressed();
// only process if this is a new key press (different from last frame)
if ((key > 0) & (~(key = lastKey))) {
if (key = 81) { let gameOver = true; } // q - quit
if (key = 32) { let paused = ~paused; } // space - pause
if ((key = 82) & (~restarting)) { // r - restart anytime (prevent rapid calls)
let restarting = true;
do restart();
return;
}
if (key = 131) { let pendingDirection = 1; } // up arrow - queue for next frame
if (key = 133) { let pendingDirection = 2; } // down arrow - queue for next frame
if (key = 130) { let pendingDirection = 3; } // left arrow - queue for next frame
if (key = 132) { let pendingDirection = 4; } // right arrow - queue for next frame
}
let lastKey = key;
return;
}
// get current speed based on whether shift is held
method int getCurrentSpeed() {
var char key;
let key = Keyboard.keyPressed();
if (key = 128) { // enter key
return speed / 2; // 2x speed when enter held
}
return speed;
}
// restart the game
method void restart() {
do Screen.clearScreen();
do snake.dispose();
do food.dispose();
let snake = Snake.new();
let food = Food.new();
do food.spawn();
let score = 0;
let gameOver = false;
let paused = false;
let speed = 150;
let lastKey = 0;
let pendingDirection = 0;
let restarting = false;
do drawUI();
return;
}
// check for input multiple times during wait period
method void waitWithInput(int milliseconds) {
var int elapsed;
var int checkInterval;
let elapsed = 0;
let checkInterval = 20; // check input every 20ms
while (elapsed < milliseconds) {
do processInput();
if (gameOver) {
return;
}
do Sys.wait(checkInterval);
let elapsed = elapsed + checkInterval;
}
return;
}
// update game state one frame
method void update() {
var boolean ateFood;
var Point nextHead, currentHead;
var int nextX, nextY, currentDirection;
if (paused | gameOver) {
return;
}
// apply pending direction change at start of frame
if (pendingDirection > 0) {
do snake.setDirection(pendingDirection);
let pendingDirection = 0;
}
// get current head and direction
let currentHead = snake.getHead();
let currentDirection = snake.getDirection();
let nextX = currentHead.getX();
let nextY = currentHead.getY();
// calculate next head position based on direction
if (currentDirection = 1) { let nextY = nextY - 8; } // up
if (currentDirection = 2) { let nextY = nextY + 8; } // down
if (currentDirection = 3) { let nextX = nextX - 8; } // left
if (currentDirection = 4) { let nextX = nextX + 8; } // right
let nextHead = Point.new(nextX, nextY);
// check food collision at next position
let ateFood = food.checkCollision(nextHead);
do nextHead.dispose();
// move snake (with or without growth)
do snake.move(ateFood);
// check collisions after movement
// check wall collision (adjusted for new header area)
if (snake.hitWall() | snake.hitSelf()) {
let gameOver = true;
return;
}
// handle food consumption
if (ateFood) {
let score = score + 10;
do food.spawn();
do showScore();
// increase speed slightly
if (speed > 80) {
let speed = speed - 2;
}
}
return;
}
// wait for game restart input
method boolean waitForRestart() {
var char key;
while (true) {
let key = Keyboard.keyPressed();
if (key = 82) { // r key
return true;
}
if (key = 81) { // q key
return false;
}
do Sys.wait(50);
}
return false;
}
// main game loop
method void run() {
var boolean restart;
while (true) {
// game running loop
while (~gameOver) {
do update();
do waitWithInput(getCurrentSpeed());
}
// game over screen
do showGameOver();
let restart = waitForRestart();
if (restart) {
do restart();
} else {
return; // quit game
}
}
return;
}
// get current score
method int getScore() {
return score;
}
// check if game is over
method boolean isGameOver() {
return gameOver;
}
// check if game is paused
method boolean isPaused() {
return paused;
}
}