Abstract: A system for generating a signal includes a touchpad including touch cells and a touch detection device for detecting the location and intensity of a pressure exerted on the touchpad; a first computer generating a first instruction based on the location and intensity of the pressure; an optical detection device for detecting a movement and/or a position, including optics for capturing images; a second computer for determining a motion parameter based on the captured images and for generating a second instruction based on the parameter; and a signal generator for producing a second signal based on the first instruction or on a first signal extracted from the first instruction, to which there is applied a special effect extracted from the second instruction; or on the second instruction or on a first signal extracted from the second instruction, to which there is applied a special effect extracted from the first instruction.