> This demo renders images through a ray-tracing technique called Signed Distance Fields.

The first sentence on the site demonstrates a lack of understanding of the program. Signed distance fields are a representation of an implicit surface, which is sampled by fragments (pixels.) They have mathematical properties which make them simple to render in a realistic manner via something like ray-tracing or ray-marching. These properties also enable the fields to compose into more complex shapes.

Yeah, I think that phrasing was slightly misleading. I was attempting to make it more understandable for the non graphics programmer audience, but you are of course right that SDFs are not necessarily a technique solely for ray tracing, though I haven't really seen them used outside of ray/path tracers.