Re: [GD-General] Multiple Inheritance and RTTI

[Peter D. <pd...@mm...>]

Noel Llopis wrote:
> On Wed, 05 Feb 2003 22:53:49 +0200
> Peter Dimov <pd...@mm...> wrote:
>
>> Out of curiosity, can someone post a real example of using the
>> QueryInterface pattern (in performance-critical code)?
>
> Sure, we use it in MechAssault.
>
> Every frame we quickly cull out any scene nodes that are not visible
> from a camera, and then for each scene node we query to see if they
> implement the IRenderable interface.  If they do, they get a render
> call.

Yes, I envisioned something like that.

What are the advantages of this approach over just providing a (possibly
empty) render() in every node type? A virtual call can never lose to a QI +
test + potential call.