physics - how to timestep properly

This seems like a really nice explanation of how to do proper time stepping in physics / time-based simulations:

http://gafferongames.wordpress.com/game-…–timestep/

Yeah I read that just recently and it seems a good way to do frame-rate independent updates in general…

There are two really useful classes in poco for this kind of things; Poco::Timestamp and Poco:Timespan. They have overloaded operators and are pretty easy to use. erik has used them in cppglue for the tween classes so the easing equations work with milliseconds instead of number of frames.

You can do things like:

  
Timestamp timestamp; //this creates a timestamp with the current time  
  
Timespan span = timestamp.elapsed();  

or

  
if(timestamp.isElapsed(span))  

Supports resolutions in microseconds and 100 nanoseconds and can be represented in diferent formats like a human readable date.

Perhaps they can be included as ofTimestamp and ofTimespan just by using typedef over the original poco classes.