PWGL is a free cross-platform visual language based on Common Lisp, CLOS and OpenGL, specialized in computer aided composition and sound synthesis. It is programmed using the Lispworks programming environment.
PWGL integrates several programming paradigms (functional, object-oriented, constraint-based) with high-level visual representation of data and it can be used to solve a wide range of musical problems. PWGL is based on many concepts and ideas that were originally developed for PatchWork (Laurson, Rueda, Duthen, Assayag, Agon) and thus credit should be given to numerous programmers, composers and researchers that were involved in this project. PWGL is developed at Sibelius Academy in Finland by a research team consisting of Mikael Laurson, Mika Kuuskankare, and Vesa Norilo. Recently the team has been augmented by Kilian Sprotte (TU, Berlin).
Currently, PWGL runs under Mac OS X and Windows XP operating systems. PWGL is distributed in two different configurations: as a standalone application, called PWGL Application, that is targeted mainly to end users, and as a developers version, PWGL Binaries, that is made available as a pre-compiled module that can be loaded on top of LispWorks.
PWGL is a visual language based on similar concepts than PatchWork. PWGL has been designed from scratch and it contains several improvements when compared with PW. For example, the graphics part of the system has been realized in OpenGL. OpenGL offers several advantages such as multi-platform support, hardware acceleration, floating-point graphics and sophisticated 2D and 3D-graphics.
ENP is used as the notational front-end in PWGL. ENP is a music notation program that has been developed in order to meet the requirements of computer aided composition, music analysis and virtual instrument control. It is intended to represent Western musical notation from 17th century onward including 20th century notation. ENP is not a full featured music typesetting program. It is, however, designed to produce automatic, reasonable musical typesetting according to the common practices.