Volume on black background

using Makie

 r = LinRange(-3, 3, 100);  # our value range

 ρ(x, y, z) = exp(-(abs(x))) # function (charge density)

 # create a Scene with the attribute `backgroundcolor = :black`,
 # can be any compatible color.  Useful for better contrast and not killing your eyes with a white background.
 scene = Scene(backgroundcolor = :black)

     r, r, r,          # coordinates to plot on
     ρ,                # charge density (functions as colorant)
     algorithm = :mip  # maximum-intensity-projection

 scene[Axis].names.textcolor = :gray # let axis labels be seen on dark background

 scene # show scene