[sharpneli]

That's the point of intrusive lists. You add a pair of pointers for every list the object is in. So when you do your physics pass using the "moving objects" list the value of the bullet is automatically updated in the "renderable objects" list without having to go trough renderable objects separately.

It was explained in the original article "If you want your structure to be in two lists at the same time, you have to add another field: " with an example.

[nly]

For games and other micro-optimised uses yeah... super-fine control over where you put your pointer pairs with respect to other data members and cache lines could be warranted. If you're optimising at that level then fine, I'd do it (with Boost Intrusive). Otherwise I'd pick up Boost Multi_Index with a couple of 'sequenced' (linked node) or random_access (vector of pointers) indices. This is non-intrusive and has the construction and overhead you want.

I just wanted to spell out that in most use cases intrusion is a sucky trade-off with no benefit.