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Revision as of 19:23, 19 May 2009 by Njb (Talk | contribs) (Key mapping)

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Drum Circle (DC) plays on the idea that the computer can act as a drum (make sound when hit) and takes advantage of the onboard sms sensor. When running DC, a graphical interface in Open GL displays a pattern of different size balls located around a circle. There is a clock hand that points to a given ball, and when hit, a note is played. At this point, the clock hand advances to the next ball in counter-clockwise motion. A melody or bass line can be played by continuously hitting the computer to trigger notes in sequence.


DC can be used for a variety of different sounds and purposes. The sound generation is detached from the graphics interface making sound generation modification easy. The first two performances of DC included a polyphonic sample playback sound as well as a polyphonic blow bottle synthesizer in Chuck. Currently, the blow bottle patch is set up in svn.


  • Copy the folder dc to any directory you like (can be found in [slork/users/njb/])
  • Done!


To run DC, two chuck patches and a separate OpenGL program must be running simultaneously. The two separate Chuck files can be run individually (, or by a separate chuck file that adds the other two ( For simplicity, the instructions below do as such.

  • Start miniAudicle and open
  • Start the virtual machine and add the shred
  • Open Terminal
  • Navigate to the dc folder
  • Type: ./dc


Once Chuck and the Drum Cirlce graphics program is running, simply hit the computer and play through the note sequence. See key mapping for more advanced control.

Key mapping

All control is managed through the graphics interface with the following controls:

  • s -full screen
  • e -rotate pattern up
  • r -rotate pattern down
  • > -adds a circle
  • < -subtracts a circle
  • [ -rotate graphics back
  • ] -rotate graphics forward
  • + -move graphics forward
  • - -move graphics backward
  • q -quits

To play more interesting melodies and use the r or e keys while striking the computer to exactly control the order of the note sequence

Advanced users

  • The main sound generation can be found at:
  • The main graphics file can be found at: dc.cpp
    • The note pattern is a global array at the top