# pattern
defines reusable rhythmic motifs mapped onto a stream of triggers. patterns impose local structure and phrasing atop incoming onset lists, regardless of whether they are generated by `grid` (metrical) or `field` (non-metrical) domains.

## families

* id 0 fixed pattern

  * description: plays the same on/off or velocity sequence every cycle
  * real-world analogy: drum machine step sequence
  * notes:

    * a: pattern index or morph position in a preset bank
    * b: density trim (0 = mute, 1 = full pattern)
    * input: accepts any trigger stream, field or grid

* id 1 rotating shift

  * description: circularly shifts the pattern each repetition
  * real-world analogy: rotating clave, staggered motif
  * notes:

    * a: shift length (scaled to trigger stream length)
    * b: shift direction (0 = left, 1 = right)
    * produces variation while preserving content

* id 2 transforming

  * description: modifies the pattern using operations like reverse, invert, or retrograde
  * real-world analogy: classical variation technique
  * notes:

    * a: transformation type (from ops list)
    * b: transformation depth or mix
    * enables evolving phrasing from static seeds

## why these were chosen

* fixed: base unit of repetition and memory
* rotating shift: variation through offset
* transforming: generative expansion from single motifs

together they cover static repetition, controlled change, and structural transformation — applicable to any sequence of trigger times, metrical or not.

## what’s not included

* fully procedural pattern generation (handled by `density` or `generative` domains)
* concatenation or chaining of patterns (handled at the `structure` layer)
* pattern-reactive feedback (disallowed by the system’s static design)

## conclusion

`pattern` brings modular phrasing to any onset stream — whether locked to a grid or distributed by a natural field. these three forms offer a minimal and powerful basis for local temporal structure, without violating the system's deterministic and parametric constraints.