Ray Marching for Dummies video.md

There are two approaches to the RayMarch function - calculate and return the position in space vs return the distance that we should walk along the rayDir. Pos might be useful when calculating normals (saves you a multiplication and addition, meh), while distance can be used for fog/shading/etc.

28:00 - Be careful when marching from some surface (to the light, for example), because by default, the distance from the point to the surface is less than the EPSILON. ^b12f24