What It Does
Elementarea is a responsive environment for invoking the four classical elements: Air, Fire, Water, and Earth. As you step on each panel representing one of the elements, a color and sound corresponding to that element are manifested in the space.
How It Works
Four force-sensitive resistors are set beneath four 12 in.2 wood panels and connected to the four resistance sensors of a PicoBoard via copper tape. When nothing is set upon a panel, its corresponding resistance sensor in Scratch measures 100, but when you step on a panel the resistance drops. Exactly how much it decreases depends on how much you weigh, how your panels are attached to the floor (I used Scotch/3M reusable mounting squares), and how hard your floor is, but responding to anything less than 90 should cover most variables. When the resistance drops, Scratch responds with an appropriate color and sound.
Elementarea has only one sprite, Elmntarea, with nine scripts. The main script loops through checking each of the resistance A–D values and when it finds one that has dropped below 90, it broadcasts a corresponding message. Here is the check for the Earth panel connected to the resistance-A sensor on the PicoBoard:
When the message invokeEarth is broadcast, two additional scripts are executed:
The costume earth is just a solid green color that fills the entire screen; the other costumes are similar (yellow for Air, red for Fire, and blue for Water). The ghost effect is used to fade the color in and out—a nicer transition than having the solid color change abruptly. The reason for broadcasting the message playSoundEarth is to play the note at the same time as the ghost transition. If we had replaced the broadcast(playSoundEarth) block with the play note (61) for (4) beats block, the repeat (100) loop that contains the ghost transition would not execute until after the note had finished playing.
The notes that play are E# (i.e., F) for Air, E for Fire, G for Water, and C# for Earth. Such are the notes for the fixed signs of the zodiac corresponding to the elements (per Paul Foster Case): Aquarius=Air, Leo=Fire, Scorpio=Water, and Taurus=Earth. For more about astrological and musical correspondences, I refer you to Astromusik by Ezra Sandzer-Bell.
I used a video projector to display the colors, and a wireless speaker placed in the center of the four panels to play the sounds.1 In the video shown above, I step on each panel briefly to show the response, but typically you would remain on the panel long enough to sufficiently invoke the element it represents, and you might strike an appropriate pose or perform an appropriate gesture such as drawing an invoking pentagram.
- Earth: one copper tape strip connected to the ‘LEFT ARROW’ input, and the other connected to ‘EARTH’ (i.e., the common ground strip on the Makey Makey board)
- Water: one strip connected to the ‘DOWN ARROW’ input; the other to ‘EARTH’
- Air: one connected to ‘UP ARROW’; the other to ‘EARTH’
- Fire: one to ‘RIGHT ARROW’, one to ‘EARTH’
Make It Better
- Add animated sigils or other glyphs that display when each color is fully illume’d.
- Play a constant tone when standing on a panel (hint: you will need to interrupt the currently playing sound when you step off of the panel or step on to another one).
- Do the same as above but with the Scratch Synth Tone experimental extension to generate the tone
- Use Makey Makey Classic to expand the variety of inputs to the seven classical planets or twelve zodiacal signs.
- Make an elemental sorcery version of Dance Dance Revolution.
- In hindsight, keeping the center clear so I could rest there between stepping on panels would have been a more graceful dance, but I had originally designed this configuration to have the light projected down on an artifact in the center as I circumambulated the space and approached each panel from the outside.