I think that's a pretty nice overview you have. One thing I would clarify is about how the objects in the scene are represented mathematically: it's done using

I think that's a pretty nice overview you have. One thing I would clarify is about how the objects in the scene are represented mathematically: it's done using 'signed distance functions' so every object you have in the scene is actually created through one of these functions which takes a point in 3D space and returns the distance to the nearest point on the object's surface to that point—which does, as you say, make the object/ray intersection testing trivial (the return value of this function is the radius of the sphere used to step along the ray). The other basic components when creating scenes to be raymarched are distance functions which combine other distance functions together. The simplest cases are just union and intersection, but it's easy to get more interesting things like smoothly blending objects together. This page is a nice reference of these 'combining' functions as well as distance functions for geometric primitives: http://mercury.sexy/hg_sdf/ http://mercury.sexy/hg_sdf/ I think that combining power is one of the main reasons to use raymarching/distance functions: building procedural content this way is faaar easier than trying to knit triangle meshes together. Additionally, if anyone wants to go a little further on the subject of building up sophisticated content by raymarching distance functions, this is an excellent talk on the subject: https://www.youtube.com/watch?v=s8nFqwOho-s https://www.youtube.com/watch?v=s8nFqwOho-s