GMSLengthKind
is defined in GMSPath.h:
/**
* kGMSEquatorProjectedMeter may be useful when specifying lengths for segment in "projected" units.
* The value of kGMSEquatorProjectedMeter, 1/(pi * EarthRadius), represents the length of one meter
* at the equator in projected units. For example to specify a projected length that corresponds
* to 100km at the equator use 100000 * kGMSEquatorProjectedMeter.
* See [GMSPath segmentsForLength:kind:], [GMSPath lengthOfKind:] and kGMSLengthProjected.
*/
extern const double kGMSEquatorProjectedMeter;
/**
* GMSLengthKind indicates the type of a length value, which can be geodesic (in meters), rhumb
* length (in meters) and projected length (in GMSMapPoint units).
*/
typedef enum {
/*
* Geodesic length, in meters, along geodesic segments. May be useful, for example, to specify
* lengths along the the trajectory of airplanes or ships.
*/
kGMSLengthGeodesic,
/*
* Rhumb length, in meters, along rhumb (straight line) segments. May be useful, for example, to
* draw a scale bar on a map. The visual size of a segment of a given length depens on the
* latitude.
*/
kGMSLengthRhumb,
/*
* Length in projected space, along rhumb segments. Projected length uses the same units as
* GMSMapPoint - the Earth equator circumference has length 2. It is possible to specify projected
* length in units corresponding to 1 meter at the equator by multiplying with
* kGMSEquatorProjectedMeter, equal to 1/(pi * EarthRadius).
*
* Projected length may be useful, for example, to specify segments with the same visual length
* regardless of latitude.
*/
kGMSLengthProjected
} GMSLengthKind;