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 ![Example rendered scene](examples/demo.jpg)
 
-A raytracer written in OCaml, following Peter Shirley's mini-book
-series [Raytracing in One Weekend][weekend].
+A raytracer written in OCaml. It supports diffuse("matte") and
+reflective("metallic") surfaces.
+
+The design of the software roughly follows Peter Shirley's mini-book
+series [Raytracing in One Weekend][weekend] which presents a raytracer
+in C++. I've adopted the programming style to suit the OCaml's
+functional style.
 
 [weekend]: http://in1weekend.blogspot.com/2016/01/ray-tracing-in-one-weekend.html