Parameters
Everything you tell Constraint Composer to do is set here,
in the Parameters section.
The three steps mirror the way a composer typically thinks about a piece:
first the overall shape (Step 1),
then the harmony (Step 2),
then the individual voices (Step 3).
Defaults are tuned so that the very first Run already works;
you only need to touch the knobs you care about.
Two buttons at the top of the section serialise the entire parameter set
to JSON (Export) and load it back (Import).
Useful for reproducing a setting later or sharing it with someone else.
Step 1: Parts
Step 1 sets the global Tempo and the form structure: the sequence of named parts that make up your piece (e.g. a simple <em>A-B-A</em>, or a longer <em>A-B-A-C-A</em>). For every part you choose the number of Bars and the time signature. Reusing the same letter (<em>A-B-A</em>) tells the solver to repeat Part A verbatim, useful for refrains; different letters get independent content.
Step 2: Chords
Step 2 generates a chord progression for each part separately, so different parts can have different harmonic colour. For every part you choose for instance:
- Key and Mode: the tonal centre (e.g. <em>C</em>, <em>D</em>) and mode (<em>major</em>, <em>minor</em>)
- Style preset: a corpus-derived chord vocabulary (e.g. <em>Bach</em>, <em>Mozart</em>), or <em>manual</em> for the default one
- Start Chord and End Chord: where the progression begins and resolves
Internally the solver finds the cheapest chord path of the right length through a weighted graph of chord transitions; you do not have to think about the graph: pick a preset and listen.
Step 3: Notes
Step 3 assigns actual pitches to each voice across all bars. The number of Voices defaults to two, with one to four voices supported; each gets its own row, identified by colour and Instrument. For every voice you set for instance:
- Instrument: General MIDI program (<em>piano</em>, <em>violin</em>, etc.)
- Pitch range: the lowest and highest notes the voice may use
- Duration: how many notes per beat (<em>whole</em>, <em>half</em>, <em>quarter</em>, <em>eighth</em>, <em>triplet</em>, or <em>sixteenth</em>)
Beyond per-voice settings, Step 3 exposes a handful of global knobs (Variety, Dissonance, Max Interval, Max Holds/Rests) plus a Counterpoint section for voice-leading constraints; Step 2 has a corresponding Creativity knob for the chord progression. The default already gives a recognisable hierarchy of motion (fast top voice, slow bottom voice); change a voice's Duration to alter the texture (e.g. all voices in quarters for a block-chord texture).