At the end of the arrays section, the case study should resemble this example solution:
namespace SpriteKind {
export const Asteroid = SpriteKind.create();
export const PowerUp = SpriteKind.create();
export const Laser = SpriteKind.create();
export const EnemyLaser = SpriteKind.create();
}
enum PowerUpType {
Health,
Score,
EnergyUp,
RechargeRateUp
}
/**
* Contains the images used in the game
*/
namespace spritesheet {
export let player: Image = img`
. . . . 8 . . . .
. . . 8 8 8 . . .
. . . 8 1 8 . . .
. . 2 8 1 8 2 . .
. 2 2 8 8 8 2 2 .
2 2 2 8 8 8 2 2 2
. . . 5 . 5 . . .
`;
export let enemy: Image = img`
5 5 . . . . 5 5
7 7 7 7 7 7 7 7
. 9 9 7 7 9 9 .
. 7 7 7 7 7 7 .
. . . 9 9 . . .
`;
export let asteroids: Image[] = [
sprites.space.spaceAsteroid0,
sprites.space.spaceAsteroid1,
sprites.space.spaceAsteroid2,
sprites.space.spaceAsteroid3,
sprites.space.spaceAsteroid4
];
export let powerUps: Image[] = [];
powerUps[PowerUpType.Health] = img`
. . . 1 1 1 1 1 . . .
. . 1 1 1 1 1 1 1 . .
. 1 1 1 1 1 1 1 1 1 .
1 1 1 2 2 1 2 2 1 1 1
1 1 2 2 2 2 2 3 2 1 1
1 1 f 2 2 2 3 2 2 1 1
1 1 f 2 2 2 2 2 2 1 1
1 1 1 f 2 2 2 2 1 1 1
. 1 1 1 f 2 2 1 1 1 .
. . 1 1 1 f 1 1 1 . .
. . . 1 1 1 1 1 . . .
`;
powerUps[PowerUpType.Score] = img`
. . . 5 5 5 5 5 . . .
. . 5 5 5 f 5 5 5 . .
. 5 5 5 f f f 5 5 5 .
5 5 5 f 5 f 5 f 5 5 5
5 5 5 5 f 5 5 5 5 5 5
5 5 5 5 5 f 5 5 5 5 5
5 5 5 5 5 5 f 5 5 5 5
5 5 5 f 5 f 5 f 5 5 5
. 5 5 5 f f f 5 5 5 .
. . 5 5 5 f 5 5 5 . .
. . . 5 5 5 5 5 . . .
`;
powerUps[PowerUpType.EnergyUp] = img`
. . . 8 8 8 8 8 . . .
. . 8 8 8 f 8 8 8 . .
. 8 8 f f f f f 8 8 .
8 8 8 f 8 d 8 f 8 8 8
8 8 8 f d d d f 8 8 8
8 8 8 f 8 d 8 f 8 8 8
8 8 8 f 8 8 8 f 8 8 8
8 8 8 f d d d f 8 8 8
. 8 8 f 8 8 8 f 8 8 .
. . 8 f f f f f 8 . .
. . . 8 8 8 8 8 . . .
`;
powerUps[PowerUpType.RechargeRateUp] = img`
. . . e e e e e . . .
. . e e e 5 4 e e . .
. e e e 5 5 e e e e .
e e e 5 5 4 4 4 e e e
e e 5 5 5 5 5 5 5 5 e
e e e e e 5 5 5 4 e e
e e e e 5 5 5 4 e e e
e e e 5 5 5 4 e e e e
. e e 5 5 4 e e e e .
. . e e 5 4 e e e . .
. . . e e e e e . . .
`;
export let laser: Image = img`
4
4
`;
}
/**
* Creates and controls the asteroids within the game
*/
namespace asteroids {
sprites.onCreated(SpriteKind.Asteroid, function (sprite: Sprite) {
sprite.setFlag(SpriteFlag.AutoDestroy, true);
setPosition(sprite, 10);
setMotion(sprite);
});
game.onUpdateInterval(1500, function () {
sprites.create(Math.pickRandom(spritesheet.asteroids), SpriteKind.Asteroid);
});
/**
* Set the initial velocities for the given sprite
* @param asteroid the asteroid to set the initial velocities of
*/
function setMotion(asteroid: Sprite) {
asteroid.vx = randint(-8, 8);
asteroid.vy = randint(35, 20);
}
/**
* Place the given sprite at a random location at the top of the screen
* @param sprite the sprite to place at the top of the screen
* @param edge how many pixels between either edge of the screen to set
*/
function setPosition(sprite: Sprite, edge: number) {
sprite.x = randint(edge, screen.width - edge);
sprite.y = 0;
}
}
/**
* Creates and controls the player's ship
*/
namespace ship {
export let player: Sprite = initialize();
export let maxCharge = 3;
export let currentCharge = maxCharge;
export let rechargeDelay = 750;
let lastRecharge = 0;
/**
* @returns a player sprite that moves with the directional buttons
*/
function initialize(): Sprite {
let sprite = sprites.create(spritesheet.player, SpriteKind.Player)
controller.moveSprite(sprite, 80, 30);
controller.A.repeatInterval = 400;
sprite.x = screen.width / 2;
sprite.y = screen.height - 20;
sprite.setStayInScreen(true);
return sprite;
}
// When the player presses A, fire a laser from the spaceship
controller.A.onEvent(ControllerButtonEvent.Pressed, function () {
fireLaser();
});
// When the player holds A, also fire the laser
controller.A.onEvent(ControllerButtonEvent.Repeated, function () {
fireLaser();
});
/**
* Fires a laser from the player's ship if they have the energy to do so
*/
function fireLaser() {
if (currentCharge > 0) {
currentCharge--;
sprites.createProjectile(spritesheet.laser, 0, -40, SpriteKind.Laser, player);
}
}
game.onUpdate(function () {
let currentTime = game.runtime();
if (currentTime - lastRecharge >= rechargeDelay) {
lastRecharge = currentTime;
if (currentCharge < maxCharge) {
currentCharge++;
}
}
});
}
/**
* Creates and controls the enemies in the game
*/
namespace enemy {
/**
* @returns an enemy sprite that is positioned at the top of the screen
*/
function createEnemy(): Sprite {
let enemy = sprites.create(spritesheet.enemy, SpriteKind.Enemy);
setPosition(enemy, 10);
enemy.vy = 10;
return enemy;
}
/**
* Place the given sprite at a random location at the top of the screen
* @param sprite the sprite to place at the top of the screen
* @param edge how many pixels between either edge of the screen to set
*/
function setPosition(sprite: Sprite, edge: number) {
sprite.x = randint(edge, screen.width - edge);
sprite.y = 0;
}
game.onUpdateInterval(200, function () {
if (Math.percentChance(5)) {
createEnemy();
}
let allEnemies = sprites.allOfKind(SpriteKind.Enemy);
for (let i = 0; i < allEnemies.length; i++) {
// Create a laser 4% of the time
if (Math.percentChance(4)) {
sprites.createProjectile(img`3`, 0, 70, SpriteKind.EnemyLaser, allEnemies[i]);
}
// follow the player
if (allEnemies[i].x < ship.player.x) {
allEnemies[i].vx = 15;
} else {
allEnemies[i].vx = -15;
}
}
});
}
/**
* Generates powerups for the player to collect
*/
namespace powerups {
let availablePowerUps = [
PowerUpType.Health,
PowerUpType.Score,
PowerUpType.EnergyUp,
PowerUpType.RechargeRateUp
];
export let responses: string[] = [];
responses[PowerUpType.Health] = "Got health!";
responses[PowerUpType.Score] = "Score!";
responses[PowerUpType.EnergyUp] = "More Energy!";
responses[PowerUpType.RechargeRateUp] = "Faster Charge!";
sprites.onCreated(SpriteKind.PowerUp, function (sprite: Sprite) {
let typeOfPowerUp = Math.pickRandom(availablePowerUps);
sprite.data = typeOfPowerUp;
sprite.setImage(spritesheet.powerUps[typeOfPowerUp]);
sprite.setFlag(SpriteFlag.AutoDestroy, true);
setPosition(sprite, 10);
setMotion(sprite);
});
/**
* Place the given sprite at a random location at the top of the screen
* @param sprite the sprite to place at the top of the screen
* @param edge how many pixels between either edge of the screen to set
*/
function setPosition(sprite: Sprite, edge: number) {
sprite.x = randint(edge, screen.width - edge);
sprite.y = 0;
}
/**
* Set the initial velocities for the given sprite
* @param powerUp the powerUp to set the initial velocities of
*/
function setMotion(powerUp: Sprite) {
powerUp.vy = 60;
}
/**
* @param powerUp sprite to get type of
* @returns the type of the given powerUp
*/
export function getType(powerUp: Sprite): PowerUpType {
return powerUp.data;
}
game.onUpdateInterval(600, function () {
if (Math.percentChance(50)) {
let currentPowerUps = sprites.allOfKind(SpriteKind.PowerUp);
if (currentPowerUps.length < 2) {
sprites.create(img`1`, SpriteKind.PowerUp);
}
}
});
}
/**
* Handle overlaps between different sprites
*/
namespace overlapevents {
// When the player hits an asteroid, damage the player and destroy the asteroid
sprites.onOverlap(SpriteKind.Player, SpriteKind.Asteroid, function (sprite: Sprite, otherSprite: Sprite) {
info.changeLifeBy(-1);
otherSprite.destroy();
});
// When the player hits an enemy, damage the player and destroy the enemy
sprites.onOverlap(SpriteKind.Player, SpriteKind.Enemy, function (sprite: Sprite, otherSprite: Sprite) {
info.changeLifeBy(-1);
otherSprite.destroy();
});
// When a laser hits an asteroid, destroy both sprites
sprites.onOverlap(SpriteKind.Laser, SpriteKind.Asteroid, function (sprite: Sprite, otherSprite: Sprite) {
info.changeScoreBy(1);
otherSprite.destroy(effects.fire, 200);
sprite.destroy();
});
// When a laser hits an enemy, destroy both sprites
sprites.onOverlap(SpriteKind.Laser, SpriteKind.Enemy, function (sprite: Sprite, otherSprite: Sprite) {
info.changeScoreBy(1);
otherSprite.destroy(effects.bubbles);
sprite.destroy();
});
// When an enemy laser hits the player, destroy the laser, say "ow!", and lose life
sprites.onOverlap(SpriteKind.Player, SpriteKind.EnemyLaser, function (sprite: Sprite, otherSprite: Sprite) {
info.changeLifeBy(-1);
otherSprite.destroy();
sprite.say("ow!", 500);
});
// When a player hits a powerup, apply the bonus for that powerup
sprites.onOverlap(SpriteKind.Player, SpriteKind.PowerUp, function (sprite: Sprite, otherSprite: Sprite) {
let powerUp: number = powerups.getType(otherSprite);
otherSprite.destroy();
sprite.say(powerups.responses[powerUp], 500);
if (powerUp == PowerUpType.Health) {
info.changeLifeBy(1);
} else if (powerUp == PowerUpType.Score) {
info.changeScoreBy(15);
} else if (powerUp == PowerUpType.EnergyUp) {
ship.maxCharge++;
} else if (powerUp == PowerUpType.RechargeRateUp) {
ship.rechargeDelay -= 20;
}
});
}
/**
* Set up the state of the game
*/
namespace status {
initialize(4, 0);
effects.starField.startScreenEffect();
/**
* Sets up the initial state of the game
* @param life the initial life to set
* @param score the initial score to set
*/
function initialize(life: number, score: number) {
info.setLife(life);
info.setScore(score);
}
info.onLifeZero(function () {
let playerContinue = game.ask("Continue?", "Cost: 50 points");
if (playerContinue) {
info.setLife(3);
info.changeScoreBy(-50);
} else {
game.over();
}
});
game.onPaint(function () {
let x = 1;
let y = screen.height - image.font5.charHeight - 1;
let color = 0x3;
if (ship.currentCharge == ship.maxCharge) {
color = 0x7;
} else if (ship.currentCharge == 0) {
color = 0x2;
}
let energyState = "energy: " + ship.currentCharge + "/" + ship.maxCharge;
screen.print(energyState, x, y, color, image.font5);
});
}