Conductive soil, video projection and Makey Makey

Description: 
 A demo set-up named "Groene vingers" demoing the Makey Makey board by utilising soil as a conductive material to switch between between two images. The switching and image handling is done within Isadora.

 
 Required components: 
 
 2 trays with moist soil 
 Makey Makey board with alligator clips and aluminium foil  
 Computer running Isadora (Isadora patch via this link ) 
 A projector pointing at the table 
 
 Order from input to output: - The 2 trays with soil form the positive and negative 'switchboard' of a circuit, which is closed when a person places both hands on it. - The Makey Makey sensor board detects when the circuit is closed and sends for example the letter 'g' as a keyboard command. - the 'g' key activity is detected in Isadora and used to fade between projections of photos, film and text and to start a sound. - Using the projection mapping (a.k.a. video mapping) function in Isadora (see online tutorial ), the images are projected in the correct perspective and within the frames of the trays. 
 
 Patch explainer: 
 
 Key strokes received from the Makey Makey 
 An algorithm preventing continuos keystrokes 
 A fading circuit to fade between projected images when a keystroke is activated by touch 
 Inverting the values for fading in an image while fading out the default image 
 Randomisation of audio startpoint to prevent repeats + green projection of displayed text 
 The default hand projection and movie which appears when triggered 
 An extra attribute to control the theatre lights