Section: New Results

OpenMusic reactive Model

In collaboration with Jean Bresson, we have extended the evaluation model of OpenMusic to integrate reactive capabilities [10] . OpenMusic (OM) is a domain-specific visual programming language designed for computer-aided music composition based on Common Lisp. It allows composers to develop functional processes generating or transforming musical data. To extend OM towards reactive applications, we have proposed to integrate its demand-driven evaluation mechanism with reactive data-driven evaluations in a same and consistent visual programming framework. To this end, we have developped the first denotational semantics of the visual language, which gives account for its demand-driven evaluation mechanism and the incremental construction of programs. We then have extended this semantics to enable reactive computations in the functional graphs. The resulting language merges data-driven executions with the existing demand-driven mechanism. This integration allows for the propagation of changes in the programs, and the evaluation of graphically-designed functional expressions as a response to external events, a first step in bridging the gap between computer-assisted composition environments and real-time musical systems.