diff options
author | Rick Walsh <rickmwalsh@gmail.com> | 2016-05-21 19:32:07 +1000 |
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committer | Dirk Hohndel <dirk@hohndel.org> | 2016-05-21 07:03:23 -0700 |
commit | b61b3a8d2891c93b1ee95a826133ede2f3a9ca6d (patch) | |
tree | 3b266c1f2098732691092da5df1acefa1fb39016 /core | |
parent | a6c8d0028e946b4713f5fe8c083cf728f086b3b8 (diff) | |
download | subsurface-b61b3a8d2891c93b1ee95a826133ede2f3a9ca6d.tar.gz |
Add functions to calculate best mix
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 <rickmwalsh@gmail.com>
Signed-off-by: Dirk Hohndel <dirk@hohndel.org>
Diffstat (limited to 'core')
-rw-r--r-- | core/dive.c | 23 | ||||
-rw-r--r-- | core/dive.h | 3 |
2 files changed, 26 insertions, 0 deletions
diff --git a/core/dive.c b/core/dive.c index c2ea11a0d..6d5ba1dbb 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 82cda6719..5988990b5 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; |