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tweakable experimental

Streamable UI elements for adjusting metrics when debugging interactives/visualisations/etc. A very light, malleable alternative to dat.gui, which is pretty great but a little tricky when handling some setups.

Not much to see here yet though!



Each "metric" is wrapped up in a node.js through stream, in that it can both be written to and read from. They each take a parent element, and any remaining arguments are up to you.

createStream = require('tweakable')(params...)

Returns a tweakable stream constructor. Takes the following arguments, listed in order:

  • init(parent) should create the element, attach it to the DOM and listen to any required events. It should also return the newly created element.
  • update(value) should update the tweakable's DOM representation to reflect a new value. This is called whenever the stream is written to, so that you can update metrics either through the UI or programatically.
  • remove() should handle removing the element from the DOM.
  • equal(a, b) should return whether two incoming values are equal. This is used to handle the changed event.

All are called from the context of the stream, and all are optional - the default values for these functions will create a text input element.

stream = createStream(parent)

Creates a tweakable stream that should be a child of the parent element.


Updates the stream's current value. Any events triggered through the UI should use this to update data.

stream.on('data', handler(value))

Emitted every time the value is updated, regardless of its value.

stream.on('change', handler(value))

Emitted every time the value is changed.


The most recently set value passed to the tweakable stream or element.