A digital picture, based on my illustration of the early 1980s, for an article in the children's science-popular magazine Kvant. The work was created in the program of vector graphics in the style of "Chaos Symmetries". The work is interesting geometrically-mathematical system for constructing flat curves with the help of a set of straight lines tangent to it, therefore I call a series of similar works as “straight lines - curves”. Specifically, a method using similar constructions in geometry is called the funny term “Mathematical Embroidery”. A wonderful example of the beauty of geometric constructions. And most importantly, an amazing effect is created, like in the “Op-art” style, when a flat two-dimensional construction of a simple curve, a cycloid, is suddenly perceived by us as a new, incredible, three-dimensional three-dimensional object, almost miraculously, which grew simply from intersecting straight lines. It is fascinating and inspiring.