The best introduction to this kind of computation that I've seen is Eric Johnston's SIGGRAPH 2016 talk[1], and the associated interactive simulator[2]. In the talk uses quantum superposition to implement a type of "quantum supersampling[3]".

[1] https://vimeo.com/180284417

[2] http://qcengine.com/

[3] https://en.wikipedia.org/wiki/Supersampling