]> Git — Sourcephile - tmp/julm/arpeggigon.git/blob - README.md
New README and name change.
[tmp/julm/arpeggigon.git] / README.md
1 Arpeggigon
2 ===
3
4 The arpeggigon is a music instrument inspired by Mark
5 Burton's [reacTogon][].
6
7 It is written in Haskell using the FRP
8 library [Yampa](http://hackage.haskell.org/package/Yampa-0.10.4) for
9 the music
10 generation, [Gtk2Hs](https://hackage.haskell.org/package/gtk-0.14.5)
11 for the Graphical User Interface (GUI)
12 and [jack](http://hackage.haskell.org/package/jack-0.7.1) for handling
13 MIDI I/O. The code to interface with the exterior world is structured
14 using reactive values and relations
15 (see
16 [this paper](http://www.cs.nott.ac.uk/~psxip1/papers/2015-HaskellSymposium-Perez-Nilsson-BridingGUIGapReactiveValues.pdf) and
17 the
18 libraries
19 [here](https://hackage.haskell.org/package/keera-hails-reactivevalues-0.2.2.0) and
20 [here](https://hackage.haskell.org/package/keera-hails-reactive-gtk-0.3)).
21
22 Install guide
23 ---
24
25 The arpeggigon needs the [GTK+ 2.0 C API](http://www.gtk.org/) and
26 the [JACK C API](http://jackaudio.org/) to be built. It is known to
27 work with GHC 7.10.3 and GHC 8.0.1.
28
29 Running the arpeggigon is then possible with:
30
31 cabal sandbox init
32 cabal install --only-dependencies
33 cabal run arpeggigon
34
35 To install the arpeggigon globally, one can call:
36
37 cabal install
38
39 This will create an executable located in
40 `<path_to_repo>/.cabal-sandbox/bin/` from where it is possible to create a
41 symbolic link to an object in the `PATH`.
42
43 ln -s <path_to_repo>/.cabal-sandbox/bin/arpeggigon <somewhere_in_PATH>/arpeggigon
44
45 Description
46 ---
47
48 ### The reacTogon
49
50 The [reacTogon][] is a musical instrument invented based upon
51 the
52 [harmonic table](https://en.wikipedia.org/wiki/Harmonic_table_note_layout),
53 a way of arranging notes where the various directions correspond to
54 meaningful musical intervals. From that layout, the reacTogon defines
55 an automaton: tokens of different kinds interact with *play heads*
56 moving around on the board, altering their directions and eventually
57 playing a note.
58
59 The arpeggigon is an extended reacTogon. It is for instance possible
60 to have multiple layers with different characteristics running in
61 parallel, or to modify the way individual notes should be played, etc.
62
63 ### Music generation
64
65 The arpeggigon doesn't directly produce music, but is
66 a
67 [MIDI](https://en.wikipedia.org/wiki/MIDI) [JACK](http://jackaudio.org/) client. It
68 then requires a JACK server to run when it is launched and to be
69 connected to a MIDI synthetizer to produce music.
70
71 ### Tokens
72
73 There are five kinds of tokens currently supported, that appear in the
74 following order in the arpeggigon's GUI:
75 * ricochet token: plays a note and reorients the play head toward the
76 direction it's pointing to,
77 * start token: like the ricochet token but generated an impulsion when
78 the machine starts,
79 * stop token: plays a note and makes the play head disappear,
80 * absorb token: like the stop token but doesn't play any note,
81 * split token: splits the impulsion into five.
82
83 ### Multiple layers
84
85 It is possible to have multiple layers running in parallel, each one
86 having it's own control settings. Adjustable parameters include:
87 * the layer beat,
88 * the strength at which notes should be played,
89 * the volume,
90 * the instrument,
91 * the beats per bar for the given layer,
92 * the possibility to make the layer restart automatically after a
93 certain number of bars, specifying if the layer should completly
94 restart or not.
95
96 ### Note attributes
97
98 Each tile, whether it's inhabited by a token or note is attributed a
99 repeat counter, telling how long a play head should stay on it.
100
101 For tiles inhabited by a token giving the possibility of a note being
102 played, it is possible to adjust some parameters, including:
103 * the note duration,
104 * an articulation, allowing the note to be played stronger depending
105 on its position in the bar,
106
107 **Warning:** *Though it appears a slide can be specified, it is for
108 now a missing feature.*
109
110 ### Button semantics
111
112 The start/restart button has a particular semantic. Pressing the start
113 button makes the machine start and turns the button into a restart
114 button. When pressed it will restart all the layers but take into
115 account the layer restart policy to know if it should completely
116 restart the layer or simply add the start heads to the already running
117 ones.
118
119 The stop button simply stops all the layers.
120
121 ### Missing features
122
123 This lists the buttons that have no effect but are yet present at the
124 moment in the GUI. This features are being worked on in priority.
125 * Recording a performance is not yet possible.
126 * Configuration saving and loading is unavailable.
127 * Slides are not implemented.
128 * Tabs are not really named.
129
130 ### Future features
131
132 This lists the features that would be nice to add to the arpeggigon at
133 some point:
134 * a nicer GUI, with the possibility to display note names on the
135 board, and see which note is being focused on.
136 * a new “random split token”, that would redirect a play head in a
137 random direction, or more generally split it in a random way.
138 * an ALSA backend for Linux.
139
140 [reacTogon]:https://www.youtube.com/watch?v=AklKy2NDpqs
141
142 Copyright and license
143 ---
144
145 Copyright 2016, Guerric Chupin and Henrik Nilsson.
146
147 The arpeggigon is licensed under the BSD 3-Clause License. A copy of
148 the license is included in the [LICENSE](LICENSE) file.