3D Modeling

[dxw]

In function api_roll_n_states(),there are three parameters:HISTORY_STREAM *hs, int nRequest and int& nActual, while nActual indicates number of delta states rolled. I'm wondering, in which situation nActual doesn't equal to nRequest ? Now I've faced with a roll_back failure.It's quite strange that next state of the active delta state is not NULL,but one we've set before.

[Mohit]

Hi

The "next" state pointer in the model is with respect to roll back, as in "the state obtained when rolling the model back one step."

Regards,
Mohit

Useful links: Delta States Documentation.

[dxw]

Hello.Thanks for your attention!

But I just think in the way you described that :

The "next" state pointer in the model is with respect to roll back, as in "the state obtained when rolling the model back one step."

What I'm faced with is when using api_roll_n_states(hs,-1,nActual), nActual returns 0. So the rollback has failed. Yet  (hs->get_active_ds)->next() shows one delta state I just want to go to.Why ? Since the "next" state is truly existed,but I can't roll back to it.