This package provides very basic GUI features to Lightarrow applications.
So far it is mostly just proof that GUIs can be expressed with signal function
tasks. Still, the Graphics.UI.Lightarrow.Modulate module provides a
high-level function to add a window with sliders to a task, which feeds the
slider positions to it as a second input signal.
This is relatively easy to use. For example, the following task draws a red rectangle of varying width and height, determined by two sliders in a window:
let f (a, []) = f (a, [0, 0])
f (a, [k1]) = f (a, [k1, 0])
f (_, k1:k2:_) = let w = (k1 + 1) * 100
h = (k2 + 1) * 100
in Node (Term (sceneRectangle Red (w, h))) []
in modulateWithSliders 2
(always (constant (arr f)))