The interval slider selects an interval (low, high) from the supplied attribute range. The (approximate) start values can be set with startvalues.

The currently selected interval is in the attribute interval and is a Tuple of (low, high). Don't change this value manually, but use the function set_close_to!(intslider, v1, v2). This is necessary to ensure the values are actually present in the range attribute.

You can click anywhere outside of the currently selected range and the closer interval edge will jump to the point. You can then drag the edge around. When hovering over the slider, the larger button indicates the edge that will react.

If the mouse hovers over the central area of the interval and both buttons are enlarged, clicking and dragging shifts the interval around as a whole.

You can double-click the slider to reset it to the values present in startvalues. If startvalues === AbstractPlotting.automatic, the full interval will be selected (this is the default).

If you set the attribute snap = false, the slider will move continously while dragging and only jump to the closest available values when releasing the mouse.

using GLMakie

f = Figure(resolution = (800, 800))
Axis(f[1, 1], limits = (0, 1, 0, 1))

rs_h = IntervalSlider(f[2, 1], range = LinRange(0, 1, 1000),
    startvalues = (0.2, 0.8))
rs_v = IntervalSlider(f[1, 2], range = LinRange(0, 1, 1000),
    startvalues = (0.4, 0.9), horizontal = false)

Label(f[3, 1], @lift(string(round.($(rs_h.interval), digits = 2))),
    tellwidth = false)
Label(f[1, 3], @lift(string(round.($(rs_v.interval), digits = 2))),
    tellheight = false, rotation = pi/2)

points = rand(Point2f0, 300)

# color points differently if they are within the two intervals
colors = lift(rs_h.interval, rs_v.interval) do h_int, v_int
    map(points) do p
        (h_int[1] < p[1] < h_int[2]) && (v_int[1] < p[2] < v_int[2])

scatter!(points, color = colors, colormap = [:black, :orange], strokewidth = 0)