Split up helper functions for interpolating gas pressure

This splits up the function to create the estimated pressures for
missing tank pressure information.

The code now has a separate pass to create the beginning and ending
pressures for segments that lack them, and fill them in to match the
overall SAC-rate for that cylinder.

In the process, it also fixes the calculation of the interpolated gas
pressure: you can see this in test-dive 13, where we switch back to the
first tank at the end of the dive.  It used to be that the latter
segment of that cylinder showed in a different color from the first
segment, showing that we had a different SAC-rate.  But that makes no
sense, since our interpolation is supposed to use a constant SAC-rate
for each cylinder.

The bug was that the "magic" calculation (which is just the pressure
change rate over pressure-time) was incorrect, and used the current
cylinder pressure for start-pressure calculation.  But that's wrong,
since we update the current cylinder pressure as we go along, but we
didn't update the total pressure_time.

With the separate phase to calculate the segment beginning/ending
pressures, the code got simplified and the bug stood out more.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Dirk Hohndel <dirk@hohndel.org>

0 files changed, 0 insertions, 0 deletions