units_utility.cpp

#include "units_utility.h"

#include "options.h"

const char *velocity_units( const units_type vel_units )
{
    if( get_option<std::string>( "USE_METRIC_SPEEDS" ) == "mph" ) {
        return _( "mph" );
    } else if( get_option<std::string>( "USE_METRIC_SPEEDS" ) == "t/t" ) {
        //~ vehicle speed tiles per turn
        return _( "t/t" );
    } else {
        switch( vel_units ) {
            case VU_VEHICLE:
                return _( "km/h" );
            case VU_WIND:
                return _( "m/s" );
        }
    }
    return "error: unknown units!";
}

units::angle normalize( units::angle a, units::angle mod )
{
    a = units::fmod( a, mod );
    if( a < 0_degrees ) {
        a += mod;
    }
    return a;
}

const char *weight_units()
{
    return get_option<std::string>( "USE_METRIC_WEIGHTS" ) == "lbs" ? _( "lbs" ) : _( "kg" );
}

const char *volume_units_abbr()
{
    const std::string vol_units = get_option<std::string>( "VOLUME_UNITS" );
    if( vol_units == "c" ) {
        return pgettext( "Volume unit", "c" );
    } else if( vol_units == "l" ) {
        return pgettext( "Volume unit", "L" );
    } else {
        return pgettext( "Volume unit", "qt" );
    }
}

const char *volume_units_long()
{
    const std::string vol_units = get_option<std::string>( "VOLUME_UNITS" );
    if( vol_units == "c" ) {
        return _( "cup" );
    } else if( vol_units == "l" ) {
        return _( "liter" );
    } else {
        return _( "quart" );
    }
}

double convert_velocity( int velocity, const units_type vel_units )
{
    const std::string type = get_option<std::string>( "USE_METRIC_SPEEDS" );
    // internal units to mph conversion
    double ret = static_cast<double>( velocity ) / 100;

    if( type == "km/h" ) {
        switch( vel_units ) {
            case VU_VEHICLE:
                // mph to km/h conversion
                ret *= 1.609f;
                break;
            case VU_WIND:
                // mph to m/s conversion
                ret *= 0.447f;
                break;
        }
    } else if( type == "t/t" ) {
        ret /= 4;
    }

    return ret;
}

double convert_weight( const units::mass &weight )
{
    double ret = to_gram( weight );
    if( get_option<std::string>( "USE_METRIC_WEIGHTS" ) == "kg" ) {
        ret /= 1000;
    } else {
        ret /= 453.6;
    }
    return ret;
}

double convert_volume( int volume )
{
    return convert_volume( volume, nullptr );
}

double convert_volume( int volume, int *out_scale )
{
    double ret = volume;
    int scale = 0;
    const std::string vol_units = get_option<std::string>( "VOLUME_UNITS" );
    if( vol_units == "c" ) {
        ret *= 0.004;
        scale = 1;
    } else if( vol_units == "l" ) {
        ret *= 0.001;
        scale = 2;
    } else {
        ret *= 0.00105669;
        scale = 2;
    }
    if( out_scale != nullptr ) {
        *out_scale = scale;
    }
    return ret;
}