What produces these distinct shapes in the Rub' al Khali seen from space?
This a great example of "self-organization" in a geomorphological system; this one an oscillating system at a fairly large scale. On a much smaller scale, you find similar structures on sand dune surfaces themselves as well as dry dusty dirt roads:



Self organization (and its scaling) is a complex process delicately dependent on just a few variables, in the case of desert dunes, wind carrying capacity, and critically, bed surface. (You can also find examples of oscillating chemical self organization in rocks when, for example, you see "tree-rings" around plagioclase crystals in anorthosites.)

The hidden (and surprising) complexity of self organization in natural systems is reflected in the difficulty in modelling these behaviors. In the case of small sand dunes:


  ...a complex process of ripple coalescence is responsible for this evolution of the ripple field. Small, fast-moving ripples catch up with and are absorbed by larger, slower forms, each such merger resulting in a growth of the mean wavelength and a decline in the relative dispersion of the wavelengths.


This mechanism may figure in modelling the formation of large dune fields:


  Because dunes reorient only at their crest terminations with a change in wind regime, the rate of formation of a new pattern of small dunes is typically faster than the rate of reorientation of the existing pattern, resulting in the superposition of simple patterns to give rise to complex patterns. Complex patterns are distinct from spatial changes in a simple pattern, and from the type of superposition that characterizes compound/complex dunes. 


There are literally tons of examples of self organization in earth systems, at all kinds of scales, but that NASA image is a stunner!