I am slowly working towards providing for bailout in the dive profile display. There are a few decisions that need to be made and I would appreciate any comment.

1) The recording of bailout events by dive computers. On Shearwater, each dive sample has a boolean that indicates whether the sample was during Loop or during Bailout. At the moment this boolean is not exposed by libdivecomputer, but Jef and myself are having discussions about making this information available in the API. I only have access to Shearwater equipment. How do other dive computers, e.g. H-W, record bailout events? Obviously, if one implements bailout, one would like to do it in a way that is as compatible with what most dive computers do. Anyone using other hardware for ccr/pscr, please comment on how your computer handles bailout events while logging?

2) Showing bailout events in the Subsurface dive profile. This would have two aspects.

    a) Indicating bailout with an icon on the dive profile. The inclusion of appropriate events is by far the easiest way to implement this. Currently the dive events are very closely tied to the libdivecomputer events, so this is somewhat limiting.

    b) Adapting the gas partial pressure graphs to reflect what the diver breathes during bailout. When rendering the dive by creating a plot_info structure for each sample, the easiest mechanism of incorporating bailout would be to use the Shearwater approach: have a byte indicating Loop or Bailout and perform the appropriate calculation for gas partial pressures.

What worries me about the above is that it uses a dual system of events as well as sample-wise boolean values. In the case of Shearwater, the events would be created from the sample-wise boolean values. If the events are entered by hand, then the sample-wise bolean values would be created using the events.

Is this approach too complex?

Kind regards,


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