diff options
| -rw-r--r-- | dive.h | 230 | ||||
| -rw-r--r-- | units.h | 243 |
2 files changed, 244 insertions, 229 deletions
@@ -33,6 +33,7 @@ static inline int same_string(const char *a, const char *b) #include <libxslt/transform.h> #include "sha1.h" +#include "units.h" #ifdef __cplusplus extern "C" { @@ -40,96 +41,6 @@ extern "C" { #include <stdbool.h> #endif -#define O2_IN_AIR 209 // permille -#define N2_IN_AIR 781 -#define O2_DENSITY 1429 // mg/Liter -#define N2_DENSITY 1251 -#define HE_DENSITY 179 -#define SURFACE_PRESSURE 1013 // mbar -#define SURFACE_PRESSURE_STRING "1013" -#define ZERO_C_IN_MKELVIN 273150 // mKelvin - -/* Salinity is expressed in weight in grams per 10l */ -#define SEAWATER_SALINITY 10300 -#define FRESHWATER_SALINITY 10000 - -/* - * Some silly typedefs to make our units very explicit. - * - * Also, the units are chosen so that values can be expressible as - * integers, so that we never have FP rounding issues. And they - * are small enough that converting to/from imperial units doesn't - * really matter. - * - * We also strive to make '0' a meaningless number saying "not - * initialized", since many values are things that may not have - * been reported (eg cylinder pressure or temperature from dive - * computers that don't support them). But sometimes -1 is an even - * more explicit way of saying "not there". - * - * Thus "millibar" for pressure, for example, or "millikelvin" for - * temperatures. Doing temperatures in celsius or fahrenheit would - * make for loss of precision when converting from one to the other, - * and using millikelvin is SI-like but also means that a temperature - * of '0' is clearly just a missing temperature or cylinder pressure. - * - * Also strive to use units that can not possibly be mistaken for a - * valid value in a "normal" system without conversion. If the max - * depth of a dive is '20000', you probably didn't convert from mm on - * output, or if the max depth gets reported as "0.2ft" it was either - * a really boring dive, or there was some missing input conversion, - * and a 60-ft dive got recorded as 60mm. - * - * Doing these as "structs containing value" means that we always - * have to explicitly write out those units in order to get at the - * actual value. So there is hopefully little fear of using a value - * in millikelvin as Fahrenheit by mistake. - * - * We don't actually use these all yet, so maybe they'll change, but - * I made a number of types as guidelines. - */ -typedef int64_t timestamp_t; - -typedef struct -{ - int seconds; -} duration_t; - -typedef struct -{ - int mm; -} depth_t; - -typedef struct -{ - int mbar; -} pressure_t; - -typedef struct -{ - int mkelvin; -} temperature_t; - -typedef struct -{ - int mliter; -} volume_t; - -typedef struct -{ - int permille; -} fraction_t; - -typedef struct -{ - int grams; -} weight_t; - -typedef struct -{ - int udeg; -} degrees_t; - struct gasmix { fraction_t o2; fraction_t he; @@ -166,96 +77,10 @@ extern double get_vertical_speed_units(unsigned int mms, int *frac, const char * extern unsigned int units_to_depth(double depth); -static inline double grams_to_lbs(int grams) -{ - return grams / 453.6; -} - -static inline int lbs_to_grams(double lbs) -{ - return rint(lbs * 453.6); -} - -static inline double ml_to_cuft(int ml) -{ - return ml / 28316.8466; -} - -static inline double cuft_to_l(double cuft) -{ - return cuft * 28.3168466; -} - -static inline double mm_to_feet(int mm) -{ - return mm * 0.00328084; -} - -static inline unsigned long feet_to_mm(double feet) -{ - return rint(feet * 304.8); -} - -static inline int to_feet(depth_t depth) -{ - return rint(mm_to_feet(depth.mm)); -} - -static inline double mkelvin_to_C(int mkelvin) -{ - return (mkelvin - ZERO_C_IN_MKELVIN) / 1000.0; -} - -static inline double mkelvin_to_F(int mkelvin) -{ - return mkelvin * 9 / 5000.0 - 459.670; -} - -static inline unsigned long F_to_mkelvin(double f) -{ - return rint((f - 32) * 1000 / 1.8 + ZERO_C_IN_MKELVIN); -} - -static inline unsigned long C_to_mkelvin(double c) -{ - return rint(c * 1000 + ZERO_C_IN_MKELVIN); -} - -static inline double psi_to_bar(double psi) -{ - return psi / 14.5037738; -} - -static inline long psi_to_mbar(double psi) -{ - return rint(psi_to_bar(psi) * 1000); -} - -static inline int to_PSI(pressure_t pressure) -{ - return rint(pressure.mbar * 0.0145037738); -} - -static inline double bar_to_atm(double bar) -{ - return bar / SURFACE_PRESSURE * 1000; -} - -static inline double mbar_to_atm(int mbar) -{ - return (double)mbar / SURFACE_PRESSURE; -} - /* Volume in mliter of a cylinder at pressure 'p' */ extern int gas_volume(cylinder_t *cyl, pressure_t p); extern int wet_volume(double cuft, pressure_t p); -static inline int mbar_to_PSI(int mbar) -{ - pressure_t p = { mbar }; - return to_PSI(p); -} - static inline int get_o2(const struct gasmix *mix) { return mix->o2.permille ?: O2_IN_AIR; @@ -521,60 +346,7 @@ extern void add_single_dive(int idx, struct dive *dive); extern void insert_trip(dive_trip_t **trip); -/* - * We keep our internal data in well-specified units, but - * the input and output may come in some random format. This - * keeps track of those units. - */ -/* turns out in Win32 PASCAL is defined as a calling convention */ -#ifdef WIN32 -#undef PASCAL -#endif -struct units { - enum { - METERS, - FEET - } length; - enum { - LITER, - CUFT - } volume; - enum { - BAR, - PSI, - PASCAL - } pressure; - enum { - CELSIUS, - FAHRENHEIT, - KELVIN - } temperature; - enum { - KG, - LBS - } weight; - enum { - SECONDS, - MINUTES - } vertical_speed_time; -}; - -/* - * We're going to default to SI units for input. Yes, - * technically the SI unit for pressure is Pascal, but - * we default to bar (10^5 pascal), which people - * actually use. Similarly, C instead of Kelvin. - * And kg instead of g. - */ -#define SI_UNITS \ - { \ - .length = METERS, .volume = LITER, .pressure = BAR, .temperature = CELSIUS, .weight = KG, .vertical_speed_time = MINUTES \ - } -#define IMPERIAL_UNITS \ - { \ - .length = FEET, .volume = CUFT, .pressure = PSI, .temperature = FAHRENHEIT, .weight = LBS, .vertical_speed_time = MINUTES \ - } extern const struct units SI_units, IMPERIAL_units; extern struct units xml_parsing_units; diff --git a/units.h b/units.h new file mode 100644 index 000000000..0e168a21e --- /dev/null +++ b/units.h @@ -0,0 +1,243 @@ +#ifndef UNITS_H +#define UNITS_H + +#ifdef __cplusplus +extern "C" { +#endif + +#define O2_IN_AIR 209 // permille +#define N2_IN_AIR 781 +#define O2_DENSITY 1429 // mg/Liter +#define N2_DENSITY 1251 +#define HE_DENSITY 179 +#define SURFACE_PRESSURE 1013 // mbar +#define SURFACE_PRESSURE_STRING "1013" +#define ZERO_C_IN_MKELVIN 273150 // mKelvin + +/* Salinity is expressed in weight in grams per 10l */ +#define SEAWATER_SALINITY 10300 +#define FRESHWATER_SALINITY 10000 + +/* + * Some silly typedefs to make our units very explicit. + * + * Also, the units are chosen so that values can be expressible as + * integers, so that we never have FP rounding issues. And they + * are small enough that converting to/from imperial units doesn't + * really matter. + * + * We also strive to make '0' a meaningless number saying "not + * initialized", since many values are things that may not have + * been reported (eg cylinder pressure or temperature from dive + * computers that don't support them). But sometimes -1 is an even + * more explicit way of saying "not there". + * + * Thus "millibar" for pressure, for example, or "millikelvin" for + * temperatures. Doing temperatures in celsius or fahrenheit would + * make for loss of precision when converting from one to the other, + * and using millikelvin is SI-like but also means that a temperature + * of '0' is clearly just a missing temperature or cylinder pressure. + * + * Also strive to use units that can not possibly be mistaken for a + * valid value in a "normal" system without conversion. If the max + * depth of a dive is '20000', you probably didn't convert from mm on + * output, or if the max depth gets reported as "0.2ft" it was either + * a really boring dive, or there was some missing input conversion, + * and a 60-ft dive got recorded as 60mm. + * + * Doing these as "structs containing value" means that we always + * have to explicitly write out those units in order to get at the + * actual value. So there is hopefully little fear of using a value + * in millikelvin as Fahrenheit by mistake. + * + * We don't actually use these all yet, so maybe they'll change, but + * I made a number of types as guidelines. + */ +typedef int64_t timestamp_t; + +typedef struct +{ + int seconds; +} duration_t; + +typedef struct +{ + int mm; +} depth_t; + +typedef struct +{ + int mbar; +} pressure_t; + +typedef struct +{ + int mkelvin; +} temperature_t; + +typedef struct +{ + int mliter; +} volume_t; + +typedef struct +{ + int permille; +} fraction_t; + +typedef struct +{ + int grams; +} weight_t; + +typedef struct +{ + int udeg; +} degrees_t; + +static inline double grams_to_lbs(int grams) +{ + return grams / 453.6; +} + +static inline int lbs_to_grams(double lbs) +{ + return rint(lbs * 453.6); +} + +static inline double ml_to_cuft(int ml) +{ + return ml / 28316.8466; +} + +static inline double cuft_to_l(double cuft) +{ + return cuft * 28.3168466; +} + +static inline double mm_to_feet(int mm) +{ + return mm * 0.00328084; +} + +static inline unsigned long feet_to_mm(double feet) +{ + return rint(feet * 304.8); +} + +static inline int to_feet(depth_t depth) +{ + return rint(mm_to_feet(depth.mm)); +} + +static inline double mkelvin_to_C(int mkelvin) +{ + return (mkelvin - ZERO_C_IN_MKELVIN) / 1000.0; +} + +static inline double mkelvin_to_F(int mkelvin) +{ + return mkelvin * 9 / 5000.0 - 459.670; +} + +static inline unsigned long F_to_mkelvin(double f) +{ + return rint((f - 32) * 1000 / 1.8 + ZERO_C_IN_MKELVIN); +} + +static inline unsigned long C_to_mkelvin(double c) +{ + return rint(c * 1000 + ZERO_C_IN_MKELVIN); +} + +static inline double psi_to_bar(double psi) +{ + return psi / 14.5037738; +} + +static inline long psi_to_mbar(double psi) +{ + return rint(psi_to_bar(psi) * 1000); +} + +static inline int to_PSI(pressure_t pressure) +{ + return rint(pressure.mbar * 0.0145037738); +} + +static inline double bar_to_atm(double bar) +{ + return bar / SURFACE_PRESSURE * 1000; +} + +static inline double mbar_to_atm(int mbar) +{ + return (double)mbar / SURFACE_PRESSURE; +} + +static inline int mbar_to_PSI(int mbar) +{ + pressure_t p = { mbar }; + return to_PSI(p); +} + +/* + * We keep our internal data in well-specified units, but + * the input and output may come in some random format. This + * keeps track of those units. + */ +/* turns out in Win32 PASCAL is defined as a calling convention */ +#ifdef WIN32 +#undef PASCAL +#endif +struct units { + enum { + METERS, + FEET + } length; + enum { + LITER, + CUFT + } volume; + enum { + BAR, + PSI, + PASCAL + } pressure; + enum { + CELSIUS, + FAHRENHEIT, + KELVIN + } temperature; + enum { + KG, + LBS + } weight; + enum { + SECONDS, + MINUTES + } vertical_speed_time; +}; + +/* + * We're going to default to SI units for input. Yes, + * technically the SI unit for pressure is Pascal, but + * we default to bar (10^5 pascal), which people + * actually use. Similarly, C instead of Kelvin. + * And kg instead of g. + */ +#define SI_UNITS \ + { \ + .length = METERS, .volume = LITER, .pressure = BAR, .temperature = CELSIUS, .weight = KG, .vertical_speed_time = MINUTES \ + } + +#define IMPERIAL_UNITS \ + { \ + .length = FEET, .volume = CUFT, .pressure = PSI, .temperature = FAHRENHEIT, .weight = LBS, .vertical_speed_time = MINUTES \ + } + +#ifdef __cplusplus +} +#endif + +#endif
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