Dissonance Grading

Dissonance Grading is a program by Jos Kunst (1936-1996), intended as a pre-compositionial tool and used as such by himself.

It scans and/or modifies chords along the dimension of dissonance.

The original documentation by Jos Kunst can be found in the file INTRODUCTION.txt.

The original program is a command-line tool written in Pascal (1993). The original source code, meant for the Symantec Think Pascal compiler for classic Mac OS, can be found in the directory cli/pascal/think_pascal.

With some minimal changes, mainly the removal of a pseudo-terminal window (every modern OS has a real terminal available now) and the change of the construction copy(str, 1, 1) to str[1] as a way to get the first character of a string, the code compiles with the Free Pascal compiler. This version of the code can be found in the directory cli/pascal/fpc.

The first version of my port to PHP was created in 2006. This was a port in which the procedural Pascal code was ported more or less straight to procedural PHP with no significant structural changes. It was also a CLI program, identical in its UI to the Pascal program.

Some time later, also in 2006, a web interface for the program was created. This was and is available at https://www.joskunst.net/dsg/.

In 2012 the procedural PHP code was seriously refactored to an object-oriented structure. Also a few long-standing bugs, found when comparing the outputs of the Pascal code and the PHP code, surfaced and were fixed. (The output of the Pascal code is used as the gold standard for how the program should behave.)

The PHP CLI and web interfaces both use the classes Chord.class.php and DSG.class.php and the procedural code in set_emulation.inc.php, all located in web/includes.

The PHP CLI program should work wherever you put the dsg directory:

$ cd ./cli/php
$ php dsg_cli.php

The web interface should work if you upload the contents of the web directory to your PHP-enabled web server. Some editing of web/dsg_config.inc.php may be needed.

MIDI support

MIDI support is provided by third-party libraries. See web/includes/extlib/README.md and web/js/README.md. MIDI does not seem to function in Safari.

Automated tests

An expect-lite script to test the CLI programs is avaiable, see the files cli/pascal.elt, cli/php.elt and cli/dsg_cli_test.inc.

CLI

Install expect-lite, see here for instructions.

Make sure that the environment variable EL_REMOTE_HOST is set to none:

$ export EL_REMOTE_HOST=none

php-cli

$ cd cli
$ expect-lite -c php.elt

Pascal

Download the Free Pascal compiler and compile cli/pascal/fpc/dsgrading.p to an executable called dsg. On Mac OS X 12.6.2 on an Intel Mac mini I used the following command:

$ fpc dsgrading.p -odsg

Make sure that the resulting binary dsg is in your PATH. Then:

$ cd cli
$ expect-lite -c pascal.elt

Lots of terminal output, it should conclude with

##Overall Result: PASS.

PHPUnit tests

Unit tests (written for PHPUnit) for the PHP DSG class are available in web/test.

$ cd web/test
$ composer install
$ vendor/bin/phpunit DSGTest.php

Expected output:

PHPUnit 9.5.0 by Sebastian Bergmann and contributors.

.......................................                           39 / 39 (100%)

Time: 00:04.222, Memory: 4.00 MB

OK (39 tests, 39 assertions)

The PHP code runs correctly under PHP 7.4. Not tested under PHP 8.

Released under the terms of version 2 of the GNU General Public License.

copyright (c) 1993 - 2022 Jos Kunst, the Jos Kunst heirs.

Contact: Jan Pieter Kunst