Add helper function for doing depth unit calculations

[ext/subsurface.git] / dive.c

diff --git a/dive.c b/dive.c
index 1b906ee43bd9a7e86db41d08cc5d3f288732a012..41bbabd698868bf43c90555acc38d13a83b41a9c 100644 (file)
--- a/dive.c
+++ b/dive.c
@@ -5,6 +5,31 @@
 
 #include "dive.h"
 
+double get_depth_units(unsigned int mm, int *frac, const char **units)
+{
+       int decimals;
+       double d;
+       const char *unit;
+
+       switch (output_units.length) {
+       case METERS:
+               d = mm / 1000.0;
+               unit = "m";
+               decimals = d < 20;
+               break;
+       case FEET:
+               d = mm_to_feet(mm);
+               unit = "ft";
+               decimals = 0;
+               break;
+       }
+       if (frac)
+               *frac = decimals;
+       if (units)
+               *units = unit;
+       return d;
+}
+
 struct dive *alloc_dive(void)
 {
        const int initial_samples = 5;