This sketch was made using the Processing framework. I used a 49-key MIDI keyboard to manipulate the blocks. Playing a key causes its associated block to release (1 per key). Adjusting the Modulation wheel (it starts completely off) increases or decreases the gravity pull of the blocks to be released. Adjusting the volume knob on the MIDI keyboard (it starts at its lowest setting) gradually inverts the colors on the screen, its level is controllable by the knob.

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