RFC: PSCR dive plots: Part 2.

[Anton Lundin]

On 13 March, 2018 - Robert Helling wrote:

> > 
> > A setpoint change to 0 is sort of a clever hack which just works for
> > planed/setpoint-only CCR dives, and not for CCR dives with po2-sensors,
> > or SCR dives.
> > 
> > 
> > I'd suggest we clean that up into some bailout sematics which works for
> > both SCR and CCR code, with or without o2 sensors.
> > 
> > 
> > If we implement that as a divemode switching event, a gaschange event
> > with some special flags, i don't really have a opinion until i see a
> > real suggestion. Nothing says we can't have a gaschange event which
> > switches to the same gas as we're currently using...
> 
> You could always interpret „gas switch“ not as „switch of gas in cylinder“ but as „switch of breathing gas“ as that what PSCR divers experience when going from the loop to OC.
> 
> I would say, the main difference is to make „PSCR mode“ not a global thing for a dive but more local in time. Note that this is already the case for „CCR mode“: We have set point that can change over time with 0 indicating OC and „CCR mode“ in a more strict sense (as in the combo box) is simply a dive that has at least at some part non-zero set-point (but we don’t use that to determine the breathing gas at any moment).
> 
> Does that make sense?

Yep.

But, currently we're using gaschange events to represent the switching
of OC gas _AND_ the switching of diluent, and we're using setpoint to
switch between CCR-setpoints and OC, if we're not using pO2 sensors.

Intertwining PSCR mode with all of that just doesn't make sense.


I'd suggest we just convert the whole thing into a mode switch event,
and let that switch between OC, CCR and PSCR, independent of everything
else. That could be implemented as a bailout event between whatever mode
you're in and OC, or a dedicated mode switch event.

Ie CCR + bailout -> OC on you're current diluent, and so on.


//Anton


-- 
Anton Lundin	+46702-161604