RBS CODE · MINI GAME LIBRARY

WHAT DO YOU WANT TO HAPPEN?

Search by your idea, not by a function name.

Most beginner games use only 5 ideas: move → detect a touch → change something → move/hide something → win or lose.

Move a player with keys

moveWithKeys(item, speed, up, down, left, right)

moveWithKeys(player, 12,
  "ArrowUp", "ArrowDown",
  "ArrowLeft", "ArrowRight");

Use this once near the start.

Know when two things touch

touching(item1, item2)

if (touching(player, coin)) {
    // what happens next?
}

Usually belongs inside an IF.

Add or subtract a number

changeNumber(number, amount, display)

score = changeNumber(score, 1, scoreText);
health = changeNumber(health, -1, healthText);

Put an object somewhere random

randomPosition(item, gameArea)

randomPosition(coin, game);

Keep player inside the game

keepInside(item, gameArea)

keepInside(player, game);

Change words on screen

setText(item, text)

setText(message, "YOU WIN!");

Hide or show something

hide(item) / show(item)

hide(key);
show(door);

Move something by pixels

move(item, xChange, yChange)

move(enemy, -5, 0);
move(rocket, 0, -10);

Put something at an exact place

place(item, x, y)

place(player, 20, 120);

Make an enemy chase the player

moveToward(enemy, target, speed)

function gameLoop() {
    moveToward(enemy, player, 2);
}
setInterval(gameLoop, 30);

Count down

startCountdown(seconds, display, finished)

startCountdown(20, timeText, function() {
    setText(message, "TIME UP!");
});

Know if something reached an edge

atEdge(item, gameArea, side)

if (atEdge(car, game, "bottom")) {
    place(car, 200, 0);
}

Don't browse forever. Say the rule out loud: “WHEN ___ happens, THEN ___.” Search for the verb in that sentence.