Tag Archives: World of Goo

Designing Sound Juggler

The premise for our first project was clear: a game simple enough that could be created in one or two months, without compromising quality.

Nowadays, physics is usually the answer to these constraints (just in case you have been living in a cave for some years, check 2DBoy’s World of Goo and Petri Purho’s Crayon Physics Deluxe), so we decided to play a little bit with Unity’s built-in physics engine.

Gameplay design

We came up with a basic game mechanic: juggling. The game would be centered on keeping an increasing number of balls in midair by simply touching the screen to create bumpers (as in pinball games), which would grow and fade, quickly disappearing. Balls would be thrown upwards after hitting a bumper, awarding points with each hit. Finally, bumpers placed higher would be weaker than those placed in lower regions, and they would also lose strength while fading.

Easy enough! Collisions, gravity and thrust forces would be handled by the physics engine, so we would focus on tunning gameplay, designing additional features and adding some bells and whistles…

Visual design

We wanted a bright neon look, so our balls… er… our juggling balls are represented by light glows, while bumpers look like laser rings. Moreover, glows are  even brighter when they collide, and they leave a trail and some good old-school particles behind them: the older the glow, the larger the trail.

We also added two particle effects. One of them created bright sparks with each collision. The other one was inspired by Futurama’s opening animation: when a new glow comes into play, bright rays of light spout out from the lower part of the screen.

Audio design

We also wanted Sound Juggler to be a musical experience. Three unique music themes were composed, each one spawning five tracks that feature increasingly more complex arrangements. Which track is played depends on the number of glows in game. That way, music is quiet with one glow but it fills your ears with five, changing continually depending on how you play.

We also divided space in a number of vertical bands, assigning each band a note and a given musical instrument. Obviously, scales and sounds were chosen to fit the underlying soundtrack. Each time a glow collides with a bumper or with another glow, a note is emitted depending on the glow’s position. It results quite fascinating listening to melodies that emerge from almost-random collisions!

Powerups

Gameplay is seasoned with three powerups that modify different conditions temporally, both positively (green icons) and negatively (red icons). They affect three variables: bumper size, bumper fade time and glow speeds. A fourth powerup, the skull, ends the game. However, the probability of skulls appearing only increases significatively if the player places bumpers indiscriminately, forcing her to play wisely.

Scoring system

We wanted scores to grow exponentially if the player played well, and we came up with a nice but rather obscure scoring system based on multipliers that fulfilled our goal. It uses the following values:

  1. Base points: with each glow-bumper hit, the base amount of points is set. Older glows award more points, using the following progression: 10 seconds or younger, 1 point; 20 seconds, 2 points, 30 seconds or older, 3 points (p)
  2. Difficulty level multiplier: easy mode x1, normal mode x2, difficult mode x3 (d)
  3. Square of number of glows in game multiplier (g^2)
  4. Hits in a row multiplier: number of consecutive glow-bumper hits without losing a glow (r)
  5. Mid-air collisions multiplier: number of glow-glow collisions between glow-bumper hits (c)
  6. Height modifier: measured between zero (higher play region) and one (lower play region). Playing in the lower region is risky (if you miss a glow, you will probably lose it!), but it is rewarded! Thanks to this modifier, the same glow may score 1 point… or many thousands! (h)

Thus, each glow-bumper hit awards points using the following expression:

points = p · d · (g^2) · (1 + r) · c · h

You may be wondering whether all this was necessary. Well… it serves its purpose! You get more points if you dare to play in difficult modes, if you keep many glows in play, if you play in lower regions and if you produce sound from glow-glow collisions. What for?

You will unlock all music themes and Etch Your Name In History…

Enjoy Sound Juggler: a game that is meant to be played with, at least, three senses.

… until you delete Sound Juggler from your iPhone, I guess. Which of course you won’t do because you will love it.

Watch the in-game trailer, it looks great, although it will look even better in your own iPhone. And do not forget your headphones!