[jcelerier]

A rework of the Pattern sequencer (Patternist): what a step can hold, how lanes relate in time, a full editor with a Rings view, and an engine that is real-time safe and never leaves a note sounding.

Depends on ossia/libossia#962 (token_request::for_each_quantification_date). The submodule points at that commit.

Steps and lanes

• Per step: velocity, velocity random, chance, timing, timing random, gate, ratchet (1 to 8), pace (bends the spacing of a ratchet's hits), pitch, pitch random, and a condition (fill, not fill, first, not first, pass A of B).
• Ties hold the note struck before them. A tie strikes again when it ratchets or changes pitch, and its gate can end the note.
• Per lane: its own length and rate (polymeter), velocity, mute and solo. For velocity, pitch and timing, the lane picks whether the whole note shares one random value or each hit of a ratchet draws its own.
• Inputs: Fill, Density, Velocity, Swing, Ratchet (a continuous multiplier), Pace, and Repeat time (synced or in seconds).

Layer and node

• The grid fills its layer. On the timeline, steps fall where they play, on the parent's bars and signatures.
• Drag to paint, Shift to tie, right-click to clear. Mute and solo are in the lane menu.
• Shorter lanes repeat across the longest one, drawn as editable cells. Notes show velocity, gate, timing, chance, ratchets and conditions.
• Colours come from the skin and follow skin changes.

Editor

• Opens as the process's UI (window, side panel or central view).
• Pattern bank: duplicate, remove, and the playing and next patterns marked.
• Toolbar:
  • select, copy, paste, clear;
  • rotate, random;
  • transpose by -12, -1, +1, +12;
  • steps and rate, add lane.
• Lane cards: name, mute and solo, steps and rate. Steps and rate can be dragged, and double-clicked to follow the pattern.
• Parameter bars:
  • one button per parameter, with Random and Reset;
  • Shift-drag moves all bars;
  • Alt-drag blends them towards a random state.
• Step selection across lanes by time. Copy and paste land on the lane and step under the mouse.
• Generators: random, Euclidean (replace, add, mask).
• Rings: the lanes as concentric rings, each its own loop. The selected lane is emphasised, and the centre shows the notes struck while playing.

Engine

• No allocation on the audio thread. Controls are clamped and NaN is ignored, both from the inlets and from the GUI.
• Notes in flight are counted per note. Releases are ordered so no note is stranded. Lanes that are removed release their notes.
• The event queue is sized for the worst case.
• A transport jump repositions the pattern. Lanes added during playback, or given another rate or length, join in time.
• The GUI reads what the engine publishes through atomics.

Loading and undo

• Documents and pastes are brought into range: NaN, huge divisions, lane count, current pattern, channel.
• An ongoing edit follows the pattern it is made on. Undoing a selection past the end gives the list back.

Tests

• test_unit_patternist_node: engine, timing, ratchets, ties, spreads.
• test_unit_patternist_edit: edits, layout, generators, transpose.
• test_unit_patternist_port: ports, serialization, clipboard.
• test_unit_patternist_robustness:
  • real-time allocation counting;
  • stuck notes;
  • hostile documents;
  • the GUI/engine race;
  • skin changes;
  • paint cost.
    Measurements and renders run on demand.

🤖 Generated with Claude Code

https://claude.ai/code/session_01FCfP6rUUXFnGw6VoTiRCWB

[coveralls]

Coverage is 49.151% — feature/pattern-sequencer-ui into master. No base build found for master.