A circular component that rotates from left to right to set numerical values.

Similar to the Slider in functionality.


Value number

The value returned by the position of the knob, ranging from -100 to 100.

IsMoving boolean read only

Returns true if the user is moving the knob.


KnobValueChangeEvent : { Value number, Type string }

Triggered when the knob is moved.
* Value is the respective value given by the knob's position
* Type is "KnobValueChangeEvent"


A simple code using some math to map knob's value into the hue of a LED's color:

-- a function that maps "value"
-- from a scale of "src_from" to "src_to"
-- into a scale of "tgt_from" to "tgt_to"
function map(value, src_from, src_to, tgt_from, tgt_to)
	return ((value - src_from) / (src_to - src_from) * (tgt_to - tgt_from)) + tgt_from

-- turn LED on at startup
gdt.Led0.State = true

function update()
	-- map slider -100,100 to hue 0,360
	local hue = map(gdt.Knob0.Value, -100, 100, 0, 360)
	-- set LED color to hue
	gdt.Led0.Color = ColorHSV(hue, 100, 100)