yes, using composition instead of inheritance, as well as a "Structure of Arrays" (SoA) instead of an "Array of Structures" (AoS), to form a loose collection of

yes, using composition instead of inheritance, as well as a "Structure of Arrays" (SoA) instead of an "Array of Structures" (AoS), to form a loose collection of arrays one can iterate over very quickly, and add properties to at run time, to program games is a mature game architecture described by http://en.wikipedia.org/wiki/Entity_component_system http://en.wikipedia.org/wiki/Entity_component_system which has been popular in the last decade. Oddly Eric never mentions ECS or SoA in the series, even though it solves the problem. (He only suggests in part 5 to use a Rule Engine, instead of inheritance)