Best mix O2 calculated based on planner Bottom O2 preference Best mix He calculated based on EAD of 30m (should be made user-configurable)
Signed-off-by: Rick Walsh <[email protected]> --- core/dive.c | 23 +++++++++++++++++++++++ core/dive.h | 3 +++ 2 files changed, 26 insertions(+) diff --git a/core/dive.c b/core/dive.c index c2ea11a..6d5ba1d 100644 --- a/core/dive.c +++ b/core/dive.c @@ -3639,3 +3639,26 @@ int get_depth_at_time(struct divecomputer *dc, unsigned int time) } return depth; } + +//Calculate O2 in best mix +fraction_t best_o2(depth_t depth, struct dive *dive) +{ + fraction_t fo2; + + fo2.permille = (prefs.bottompo2 * 100 / depth_to_mbar(depth.mm, dive)) * 10; //use integer arithmetic to round down to nearest percent + return fo2; +} + +//Calculate He in best mix. O2 is considered narcopic +fraction_t best_He(depth_t depth, struct dive *dive) +{ + fraction_t fhe; + int ead = 30000; //this should be user-configurable + int pnarcotic, ambient; + pnarcotic = depth_to_mbar(ead, dive); + ambient = depth_to_mbar(depth.mm, dive); + fhe.permille = (100 - 100 * pnarcotic / ambient) * 10; //use integer arithmetic to round up to nearest percent + if (fhe.permille < 0) + fhe.permille = 0; + return fhe; +} diff --git a/core/dive.h b/core/dive.h index 82cda67..5988990 100644 --- a/core/dive.h +++ b/core/dive.h @@ -402,6 +402,9 @@ extern void picture_free(struct picture *picture); extern int explicit_first_cylinder(struct dive *dive, struct divecomputer *dc); extern int get_depth_at_time(struct divecomputer *dc, unsigned int time); +extern fraction_t best_o2(depth_t depth, struct dive *dive); +extern fraction_t best_He(depth_t depth, struct dive *dive); + static inline int get_surface_pressure_in_mbar(const struct dive *dive, bool non_null) { int mbar = dive->surface_pressure.mbar; -- 2.5.5 _______________________________________________ subsurface mailing list [email protected] http://lists.subsurface-divelog.org/cgi-bin/mailman/listinfo/subsurface
