loop-grid

An observable collection of looped event sequences shaped to a grid.

Install via npm

$ npm install loop-grid

API

var LoopGrid = require('loop-grid')

var loopGrid = LoopGrid(options)

Returns an observable instance of LoopGrid.

options:

• scheduler: (required) instance of Bopper
• triggerEvent: (required) function(event) called for every event to be triggered
• audio: (required) instance of AudioContext

loopGrid()

Return the current object descriptor (state).

loopGrid.set(descriptor)

Set the current object descriptor (state).

loopGrid.shape (Observ([rows, cols]))

Included in state.

loopGrid.loops (Observ([ { length: 8, events: [] }, ... ]))

Included in state.

loopGrid.targets (Observ([ids]))

Mapping of grid loops to ids.

Included in state.

loopGrid.loopLength (Observ(8))

Included in state.

var removeListener = loopGrid.onEvent(listener)

var event = {
  id: String,
  event: 'start' | 'stop',
  position: Number, // beat
  time: Number, // based on
  args: Array
}

var value = loopGrid.loopPosition()

var removeListener = loopGrid.loopPosition(listener)

var arrayGrid = loopGrid.grid()

Returns ArrayGrid based on loopGrid.targets and loopGrid.shape.

`var removeListener = loopGrid.grid(listener)

var grid = loopGrid.playing()

Returns ArrayGrid of true values where target is currently being triggered.

var removeListener = loopGrid.playing(listener)

var grid = loopGrid.active()

Returns ArrayGrid of true values where target has a current loop.

var removeListener = loopGrid.active(listener)

loopGrid.destroy()

Looper

var Looper = require('loop-grid/looper')

var looper = Looper(loopGrid)

var loops = looper()

var removeListener = looper(listener)

var currentlyRecording = looper.recording()

var removeListener = looper.recording(listener)

looper.store()

looper.flaten()

var releaseTransform = looper.transform(func(input, args..), args)

Pass in a function to add to transform stack. input is an instance of ArrayGrid and should return either the modified input or a new instance of ArrayGrid.

looper.undo()

looper.redo()

looper.isTransforming()

Computed Flags

var computeFlags = require('loop-grid/compute-flags')

Computed Targets

var computeTargets = require('loop-grid/compute-targets')

Selector

Range selector for loop-grid.

API

var Selector = require('loop-grid/selector')

var selection = Selector(shape)

Returns an extended instance of ObservGrid with shape specified.

selector.start(inputGrid, done)

Pass in an observable ArrayGrid. done will be called on stop or before subsequent start.

Any truthy values will trigger a selection. Simultaneous true values will trigger range selection. selection will have .set(selectedIndexes) called on every change.

selector.clear()

Sets selection to an empty array.

selector.stop()

Release watch of inputGrid and call done.

Transforms

Holder

Beat stutter/looper

var Holder = require('loop-grid/transforms/holder')

var holder = Holder(transform)

Pass loopGrid.transform to this constructor.

holder.setLength(length)

Choose the length (in beat decimal) of the stutter effect.

holder.start(position[, indexes, done])

Loop events in specified indexes (or all if not specified) from position to position + length. Ensure each event length is no longer than specified length (truncating if necessary).

Automatically calls holder.stop() first if there is a current hold in progress.

holder.stop()

Release transform and call done if specified.

Mover

Move selected ranges of loops to new origin.

var Mover = require('loop-grid/transforms/mover')

var mover = Mover(transform)

Pass loopGrid.transform to this constructor.

mover.start(inputGrid, selectedIndexes, done)

Finds the top-left most coordinates in selectedIndexes, and uses this as the start origin. Any true values in inputGrid will call transform with a function that moves the values from selectedIndexes to the new origin. Multiple true values will cause the selectedIndexes to be duplicated.

mover.stop()

Release any pending transform and stop watching inputGrid.

Repeater

var Repeater = require('loop-grid/transforms/repeater')

`var repeater = Repeater(transform)

Pass loopGrid.transform to this constructor.

repeater.start(inputGrid, length)

Held notes will call transform with a function that creates a repeating note with length length / 2 at the rate of specified length.

repeater.setLength(length)

repeater.stop()

Release the inputGrid.

Suppressor

Suppress selected loops

var Suppressor = require('loop-grid/transforms/suppressor')

var suppressor = Suppressor(transform, shape[, stride])

Pass loopGrid.transform to this constructor.

Returns an extended observ instance containing instances of array-grid with true values at coords where currently suppressed.

suppressor.start(indexes, done)

Calls transform with a function that suppresses all indexes specified.

suppressor.stop()

Release suppression transform.

License

AGPL-3.0