function update() {
if (gameState === GAME_STATE.PLAY) {
asteroids.update();
playerShip.update();
checkShipAndAsteroidCollision();
checkShipLaserAndAsteroidCollision();
} else {
return;
}
}
function draw() {
canvasContext.clearRect(0, 0, viewPort.width, viewPort.height);
drawScore();
drawLives();
if (gameState === GAME_STATE.START) {
drawStartScreen();
} else if (gameState === GAME_STATE.PLAY) {
playerShip.draw(canvasContext);
asteroids.draw(canvasContext);
} else if (gameState === GAME_STATE.PAUSE) {
console.log('Paused');
} else if (gameState === GAME_STATE.OVER) {
endGame();
} else {
drawStartScreen();
}
}
controls.on('right', () => {
if (gameState === GAME_STATE.PLAY) {
playerShip.moveRight();
}
});
controls.on('left', () => {
if (gameState === GAME_STATE.PLAY) {
playerShip.moveLeft();
}
});
(function main() {
'use strict';
// Game Globals
const GAME_STATE = { START: 'START', PLAY: 'PLAY', PAUSE: 'PAUSE', OVER: 'OVER' };
let canvasContext = document.getElementById('GameCanvas').getContext('2d');
let gameState = GAME_STATE.START;
let gameScore = 0;
let gameLives = 3;
let viewPort = {
width: 720,
height: 480
};
//region Game
let playerShip = new Ship({viewPort, lasers: new LaserCollection()});
let asteroids = new AsteroidCollection({viewPort: viewPort});
let controls = new Controls();
let game = new Game({init, update, draw});
game.start();
function init() {
window.setInterval(() => {
if (gameState === GAME_STATE.PLAY) {
asteroids.addAsteroid();
}
}, 140 - (viewPort.width / 100));
}
function update() {
if (gameState === GAME_STATE.PLAY) {
asteroids.update();
playerShip.update();
checkShipAndAsteroidCollision();
checkShipLaserAndAsteroidCollision();
} else {
return;
}
}
function draw() {
canvasContext.clearRect(0, 0, viewPort.width, viewPort.height);
drawScore();
drawLives();
if (gameState === GAME_STATE.START) {
drawStartScreen();
} else if (gameState === GAME_STATE.PLAY) {
playerShip.draw(canvasContext);
asteroids.draw(canvasContext);
} else if (gameState === GAME_STATE.PAUSE) {
console.log('Paused');
} else if (gameState === GAME_STATE.OVER) {
endGame();
} else {
drawStartScreen();
}
}
function checkShipAndAsteroidCollision() {
asteroids.list.forEach((asteroid, index) => {
if (CollisionDetection.check(playerShip, asteroid)) {
asteroids.list.splice(index, 1);
removeLife();
}
});
};
function checkShipLaserAndAsteroidCollision() {
playerShip.lasers.list.forEach((laser, laserIndex) => {
asteroids.list.forEach((asteroid, asteroidIndex) => {
if (CollisionDetection.check(laser, asteroid)) {
playerShip.lasers.list.splice(laserIndex, 1);
asteroids.list.splice(asteroidIndex, 1);
addScore();
}
});
});
};
//endregion
//region Key Game Controls
controls.on('left', () => {
if (gameState === GAME_STATE.PLAY) {
playerShip.moveLeft();
}
});
controls.on('right', () => {
if (gameState === GAME_STATE.PLAY) {
playerShip.moveRight();
}
});
controls.on('up', () => {
if (gameState === GAME_STATE.PLAY) {
playerShip.moveUp();
}
});
controls.on('down', () => {
if (gameState === GAME_STATE.PLAY) {
playerShip.moveDown();
}
});
controls.onKey('space', () => {
if (gameState === GAME_STATE.PLAY) {
playerShip.fire();
}
});
controls.onKey('pause', () => {
pauseGame();
});
controls.onKey('enter', () => {
if (gameState === GAME_STATE.START || gameState === GAME_STATE.OVER) {
startNewGame();
}
});
//endregion
//region Helper Functions
function drawStartScreen() {
$('.js-start-screen').show();
}
function hideStartScreen() {
$('.js-start-screen').hide();
}
function startNewGame() {
gameLives = 3;
gameState = GAME_STATE.PLAY;
gameScore = 0;
hideStartScreen();
$('.js-game-over-screen').hide();
}
function pauseGame() {
drawPauseScreen();
if (gameState === GAME_STATE.PLAY) {
gameState = GAME_STATE.PAUSE;
} else {
gameState = GAME_STATE.PLAY;
}
}
function drawPauseScreen() {
$('.js-pause-screen').toggle();
}
function endGame() {
$('.js-game-over-screen').show();
}
function addScore() {
gameScore += 1;
}
function drawScore() {
$('.js-score').html('Score:' + gameScore);
}
function removeLife() {
if (gameLives > 0) {
gameLives -= 1;
} else {
gameState = GAME_STATE.OVER;
}
}
function drawLives() {
$('.js-lives').html('Lives:' + gameLives);
}
//endregion
}());
controls.onKey('space', () => {
if (gameState === GAME_STATE.PLAY) {
playerShip.fire();
}
});
controls.on('down', () => {
if (gameState === GAME_STATE.PLAY) {
playerShip.moveDown();
}
});
controls.on('up', () => {
if (gameState === GAME_STATE.PLAY) {
playerShip.moveUp();
}
});