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cc_library(
name = "openlocationcode",
srcs = [
"openlocationcode.cc",
],
hdrs = [
"codearea.h",
"openlocationcode.h",
],
copts = ["-pthread"],
linkopts = ["-pthread"],
visibility = ["//visibility:public"],
deps = [
":codearea",
],
)
cc_library(
name = "codearea",
srcs = [
"codearea.cc",
],
hdrs = [
"codearea.h",
],
visibility = ["//visibility:private"],
)
cc_test(
name = "openlocationcode_test",
size = "small",
srcs = ["openlocationcode_test.cc"],
copts = [
"-pthread",
"-Iexternal/gtest/include",
],
data = [
"//test_data",
],
linkopts = ["-pthread"],
deps = [
":openlocationcode",
"@gtest//:main",
],
)
cc_binary(
name = "openlocationcode_example",
srcs = [
"openlocationcode_example.cc",
],
deps = [
":openlocationcode",
],
)

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project(openlocationcode)
include_directories(src ../../)
set(
SRC
codearea.cc
codearea.h
openlocationcode.cc
openlocationcode.h
)
add_library(${PROJECT_NAME} ${SRC})

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Apache License
Version 2.0, January 2004
http://www.apache.org/licenses/
TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
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# Open Location Code C++ API
This is the C++ implementation of the Open Location Code API.
# Usage
See openlocationcode_example.cc for how to use the library. To run the example, use:
```
bazel run openlocationcode_example
```
# Development
The library is built/tested using [Bazel](https://bazel.build). To build the library, use:
```
bazel build openlocationcode
```
To run the tests, use:
```
bazel test --test_output=all openlocationcode_test
```
The tests use the CSV files in the test_data folder. Make sure you copy this folder to the
root of your local workspace.
# Formatting
Code must be formatted using `clang-format`, and this will be checked in the
tests. You can format your code using the script:
```
sh clang_check.sh
```

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#include "codearea.h"
#include <algorithm>
namespace openlocationcode {
const double kLatitudeMaxDegrees = 90;
const double kLongitudeMaxDegrees = 180;
CodeArea::CodeArea(double latitude_lo, double longitude_lo, double latitude_hi,
double longitude_hi, size_t code_length) {
latitude_lo_ = latitude_lo;
longitude_lo_ = longitude_lo;
latitude_hi_ = latitude_hi;
longitude_hi_ = longitude_hi;
code_length_ = code_length;
}
double CodeArea::GetLatitudeLo() const { return latitude_lo_; }
double CodeArea::GetLongitudeLo() const { return longitude_lo_; }
double CodeArea::GetLatitudeHi() const { return latitude_hi_; }
double CodeArea::GetLongitudeHi() const { return longitude_hi_; }
size_t CodeArea::GetCodeLength() const { return code_length_; }
LatLng CodeArea::GetCenter() const {
const double latitude_center = std::min(
latitude_lo_ + (latitude_hi_ - latitude_lo_) / 2, kLatitudeMaxDegrees);
const double longitude_center =
std::min(longitude_lo_ + (longitude_hi_ - longitude_lo_) / 2,
kLongitudeMaxDegrees);
const LatLng center = {latitude_center, longitude_center};
return center;
}
} // namespace openlocationcode

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#ifndef LOCATION_OPENLOCATIONCODE_CODEAREA_H_
#define LOCATION_OPENLOCATIONCODE_CODEAREA_H_
#include <cstdlib>
namespace openlocationcode {
struct LatLng {
double latitude;
double longitude;
};
class CodeArea {
public:
CodeArea(double latitude_lo, double longitude_lo, double latitude_hi,
double longitude_hi, size_t code_length);
double GetLatitudeLo() const;
double GetLongitudeLo() const;
double GetLatitudeHi() const;
double GetLongitudeHi() const;
size_t GetCodeLength() const;
LatLng GetCenter() const;
private:
double latitude_lo_;
double longitude_lo_;
double latitude_hi_;
double longitude_hi_;
size_t code_length_;
};
} // namespace openlocationcode
#endif // LOCATION_OPENLOCATIONCODE_CODEAREA_H_

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#include "openlocationcode.h"
#include <float.h>
#include <algorithm>
#include <cmath>
#include <cstdint>
#include "codearea.h"
namespace openlocationcode {
namespace internal {
const char kSeparator = '+';
const char kPaddingCharacter = '0';
const char kAlphabet[] = "23456789CFGHJMPQRVWX";
// Number of digits in the alphabet.
const size_t kEncodingBase = 20;
// The max number of digits returned in a plus code. Roughly 1 x 0.5 cm.
const size_t kMaximumDigitCount = 15;
const size_t kPairCodeLength = 10;
const size_t kGridCodeLength = kMaximumDigitCount - kPairCodeLength;
const size_t kGridColumns = 4;
const size_t kGridRows = kEncodingBase / kGridColumns;
const size_t kSeparatorPosition = 8;
// Work out the encoding base exponent necessary to represent 360 degrees.
const size_t kInitialExponent = floor(log(360) / log(kEncodingBase));
// Work out the enclosing resolution (in degrees) for the grid algorithm.
const double kGridSizeDegrees =
1 / pow(kEncodingBase, kPairCodeLength / 2 - (kInitialExponent + 1));
// Inverse (1/) of the precision of the final pair digits in degrees. (20^3)
const size_t kPairPrecisionInverse = 8000;
// Inverse (1/) of the precision of the final grid digits in degrees.
// (Latitude and longitude are different.)
const size_t kGridLatPrecisionInverse =
kPairPrecisionInverse * pow(kGridRows, kGridCodeLength);
const size_t kGridLngPrecisionInverse =
kPairPrecisionInverse * pow(kGridColumns, kGridCodeLength);
// Latitude bounds are -kLatitudeMaxDegrees degrees and +kLatitudeMaxDegrees
// degrees which we transpose to 0 and 180 degrees.
const double kLatitudeMaxDegrees = 90;
// Longitude bounds are -kLongitudeMaxDegrees degrees and +kLongitudeMaxDegrees
// degrees which we transpose to 0 and 360.
const double kLongitudeMaxDegrees = 180;
// Lookup table of the alphabet positions of characters 'C' through 'X',
// inclusive. A value of -1 means the character isn't part of the alphabet.
const int kPositionLUT['X' - 'C' + 1] = {8, -1, -1, 9, 10, 11, -1, 12,
-1, -1, 13, -1, -1, 14, 15, 16,
-1, -1, -1, 17, 18, 19};
} // namespace internal
namespace {
// Raises a number to an exponent, handling negative exponents.
double pow_neg(double base, double exponent) {
if (exponent == 0) {
return 1;
} else if (exponent > 0) {
return pow(base, exponent);
}
return 1 / pow(base, -exponent);
}
// Compute the latitude precision value for a given code length. Lengths <= 10
// have the same precision for latitude and longitude, but lengths > 10 have
// different precisions due to the grid method having fewer columns than rows.
double compute_precision_for_length(int code_length) {
if (code_length <= 10) {
return pow_neg(internal::kEncodingBase, floor((code_length / -2) + 2));
}
return pow_neg(internal::kEncodingBase, -3) / pow(5, code_length - 10);
}
// Returns the position of a char in the encoding alphabet, or -1 if invalid.
int get_alphabet_position(char c) {
// We use a lookup table for performance reasons (e.g. over std::find).
if (c >= 'C' && c <= 'X') return internal::kPositionLUT[c - 'C'];
if (c >= 'c' && c <= 'x') return internal::kPositionLUT[c - 'c'];
if (c >= '2' && c <= '9') return c - '2';
return -1;
}
// Normalize a longitude into the range -180 to 180, not including 180.
double normalize_longitude(double longitude_degrees) {
while (longitude_degrees < -internal::kLongitudeMaxDegrees) {
longitude_degrees = longitude_degrees + 360;
}
while (longitude_degrees >= internal::kLongitudeMaxDegrees) {
longitude_degrees = longitude_degrees - 360;
}
return longitude_degrees;
}
// Adjusts 90 degree latitude to be lower so that a legal OLC code can be
// generated.
double adjust_latitude(double latitude_degrees, size_t code_length) {
latitude_degrees = std::min(90.0, std::max(-90.0, latitude_degrees));
if (latitude_degrees < internal::kLatitudeMaxDegrees) {
return latitude_degrees;
}
// Subtract half the code precision to get the latitude into the code
// area.
double precision = compute_precision_for_length(code_length);
return latitude_degrees - precision / 2;
}
// Remove the separator and padding characters from the code.
std::string clean_code_chars(const std::string &code) {
std::string clean_code(code);
clean_code.erase(
std::remove(clean_code.begin(), clean_code.end(), internal::kSeparator),
clean_code.end());
if (clean_code.find(internal::kPaddingCharacter)) {
clean_code =
clean_code.substr(0, clean_code.find(internal::kPaddingCharacter));
}
return clean_code;
}
} // anonymous namespace
std::string Encode(const LatLng &location, size_t code_length) {
// Limit the maximum number of digits in the code.
code_length = std::min(code_length, internal::kMaximumDigitCount);
// Adjust latitude and longitude so that they are normalized/clipped.
double latitude = adjust_latitude(location.latitude, code_length);
double longitude = normalize_longitude(location.longitude);
// Reserve 15 characters for the code digits. The separator will be inserted
// at the end.
std::string code = "123456789abcdef";
// Compute the code.
// This approach converts each value to an integer after multiplying it by
// the final precision. This allows us to use only integer operations, so
// avoiding any accumulation of floating point representation errors.
// Multiply values by their precision and convert to positive without any
// floating point operations.
int64_t lat_val =
internal::kLatitudeMaxDegrees * internal::kGridLatPrecisionInverse;
int64_t lng_val =
internal::kLongitudeMaxDegrees * internal::kGridLngPrecisionInverse;
lat_val += latitude * internal::kGridLatPrecisionInverse;
lng_val += longitude * internal::kGridLngPrecisionInverse;
size_t pos = internal::kMaximumDigitCount - 1;
// Compute the grid part of the code if necessary.
if (code_length > internal::kPairCodeLength) {
for (size_t i = 0; i < internal::kGridCodeLength; i++) {
int lat_digit = lat_val % internal::kGridRows;
int lng_digit = lng_val % internal::kGridColumns;
int ndx = lat_digit * internal::kGridColumns + lng_digit;
code.replace(pos--, 1, 1, internal::kAlphabet[ndx]);
// Note! Integer division.
lat_val /= internal::kGridRows;
lng_val /= internal::kGridColumns;
}
} else {
lat_val /= pow(internal::kGridRows, internal::kGridCodeLength);
lng_val /= pow(internal::kGridColumns, internal::kGridCodeLength);
}
pos = internal::kPairCodeLength - 1;
// Compute the pair section of the code.
for (size_t i = 0; i < internal::kPairCodeLength / 2; i++) {
int lat_ndx = lat_val % internal::kEncodingBase;
int lng_ndx = lng_val % internal::kEncodingBase;
code.replace(pos--, 1, 1, internal::kAlphabet[lng_ndx]);
code.replace(pos--, 1, 1, internal::kAlphabet[lat_ndx]);
// Note! Integer division.
lat_val /= internal::kEncodingBase;
lng_val /= internal::kEncodingBase;
}
// Add the separator character.
code.insert(internal::kSeparatorPosition, &(internal::kSeparator), 1);
// If we don't need to pad the code, return the requested section.
if (code_length >= internal::kSeparatorPosition) {
return code.substr(0, code_length + 1);
}
// Add the required padding characters.
for (size_t i = code_length; i < internal::kSeparatorPosition; i++) {
code[i] = internal::kPaddingCharacter;
}
// Return the code up to and including the separator.
return code.substr(0, internal::kSeparatorPosition + 1);
}
std::string Encode(const LatLng &location) {
return Encode(location, internal::kPairCodeLength);
}
CodeArea Decode(const std::string &code) {
std::string clean_code = clean_code_chars(code);
// Constrain to the maximum length.
if (clean_code.size() > internal::kMaximumDigitCount) {
clean_code = clean_code.substr(0, internal::kMaximumDigitCount);
}
// Initialise the values for each section. We work them out as integers and
// convert them to floats at the end.
int normal_lat =
-internal::kLatitudeMaxDegrees * internal::kPairPrecisionInverse;
int normal_lng =
-internal::kLongitudeMaxDegrees * internal::kPairPrecisionInverse;
int extra_lat = 0;
int extra_lng = 0;
// How many digits do we have to process?
size_t digits = std::min(internal::kPairCodeLength, clean_code.size());
// Define the place value for the most significant pair.
int pv = pow(internal::kEncodingBase, internal::kPairCodeLength / 2 - 1);
for (size_t i = 0; i < digits - 1; i += 2) {
normal_lat += get_alphabet_position(clean_code[i]) * pv;
normal_lng += get_alphabet_position(clean_code[i + 1]) * pv;
if (i < digits - 2) {
pv /= internal::kEncodingBase;
}
}
// Convert the place value to a float in degrees.
double lat_precision = (double)pv / internal::kPairPrecisionInverse;
double lng_precision = (double)pv / internal::kPairPrecisionInverse;
// Process any extra precision digits.
if (clean_code.size() > internal::kPairCodeLength) {
// Initialise the place values for the grid.
int row_pv = pow(internal::kGridRows, internal::kGridCodeLength - 1);
int col_pv = pow(internal::kGridColumns, internal::kGridCodeLength - 1);
// How many digits do we have to process?
digits = std::min(internal::kMaximumDigitCount, clean_code.size());
for (size_t i = internal::kPairCodeLength; i < digits; i++) {
int dval = get_alphabet_position(clean_code[i]);
int row = dval / internal::kGridColumns;
int col = dval % internal::kGridColumns;
extra_lat += row * row_pv;
extra_lng += col * col_pv;
if (i < digits - 1) {
row_pv /= internal::kGridRows;
col_pv /= internal::kGridColumns;
}
}
// Adjust the precisions from the integer values to degrees.
lat_precision = (double)row_pv / internal::kGridLatPrecisionInverse;
lng_precision = (double)col_pv / internal::kGridLngPrecisionInverse;
}
// Merge the values from the normal and extra precision parts of the code.
// Everything is ints so they all need to be cast to floats.
double lat = (double)normal_lat / internal::kPairPrecisionInverse +
(double)extra_lat / internal::kGridLatPrecisionInverse;
double lng = (double)normal_lng / internal::kPairPrecisionInverse +
(double)extra_lng / internal::kGridLngPrecisionInverse;
// Round everything off to 14 places.
return CodeArea(round(lat * 1e14) / 1e14, round(lng * 1e14) / 1e14,
round((lat + lat_precision) * 1e14) / 1e14,
round((lng + lng_precision) * 1e14) / 1e14,
clean_code.size());
}
std::string Shorten(const std::string &code, const LatLng &reference_location) {
if (!IsFull(code)) {
return code;
}
if (code.find(internal::kPaddingCharacter) != std::string::npos) {
return code;
}
CodeArea code_area = Decode(code);
LatLng center = code_area.GetCenter();
// Ensure that latitude and longitude are valid.
double latitude =
adjust_latitude(reference_location.latitude, CodeLength(code));
double longitude = normalize_longitude(reference_location.longitude);
// How close are the latitude and longitude to the code center.
double range = std::max(fabs(center.latitude - latitude),
fabs(center.longitude - longitude));
std::string code_copy(code);
const double safety_factor = 0.3;
const int removal_lengths[3] = {8, 6, 4};
for (int removal_length : removal_lengths) {
// Check if we're close enough to shorten. The range must be less than 1/2
// the resolution to shorten at all, and we want to allow some safety, so
// use 0.3 instead of 0.5 as a multiplier.
double area_edge =
compute_precision_for_length(removal_length) * safety_factor;
if (range < area_edge) {
code_copy = code_copy.substr(removal_length);
break;
}
}
return code_copy;
}
std::string RecoverNearest(const std::string &short_code,
const LatLng &reference_location) {
if (!IsShort(short_code)) {
std::string code = short_code;
std::transform(code.begin(), code.end(), code.begin(), ::toupper);
return code;
}
// Ensure that latitude and longitude are valid.
double latitude =
adjust_latitude(reference_location.latitude, CodeLength(short_code));
double longitude = normalize_longitude(reference_location.longitude);
// Compute the number of digits we need to recover.
size_t padding_length =
internal::kSeparatorPosition - short_code.find(internal::kSeparator);
// The resolution (height and width) of the padded area in degrees.
double resolution =
pow_neg(internal::kEncodingBase, 2.0 - (padding_length / 2.0));
// Distance from the center to an edge (in degrees).
double half_res = resolution / 2.0;
// Use the reference location to pad the supplied short code and decode it.
LatLng latlng = {latitude, longitude};
std::string padding_code = Encode(latlng);
CodeArea code_rect =
Decode(std::string(padding_code.substr(0, padding_length)) +
std::string(short_code));
// How many degrees latitude is the code from the reference? If it is more
// than half the resolution, we need to move it north or south but keep it
// within -90 to 90 degrees.
double center_lat = code_rect.GetCenter().latitude;
double center_lng = code_rect.GetCenter().longitude;
if (latitude + half_res < center_lat &&
center_lat - resolution > -internal::kLatitudeMaxDegrees) {
// If the proposed code is more than half a cell north of the reference
// location, it's too far, and the best match will be one cell south.
center_lat -= resolution;
} else if (latitude - half_res > center_lat &&
center_lat + resolution < internal::kLatitudeMaxDegrees) {
// If the proposed code is more than half a cell south of the reference
// location, it's too far, and the best match will be one cell north.
center_lat += resolution;
}
// How many degrees longitude is the code from the reference?
if (longitude + half_res < center_lng) {
center_lng -= resolution;
} else if (longitude - half_res > center_lng) {
center_lng += resolution;
}
LatLng center_latlng = {center_lat, center_lng};
return Encode(center_latlng, CodeLength(short_code) + padding_length);
}
bool IsValid(const std::string &code) {
if (code.empty()) {
return false;
}
size_t separatorPos = code.find(internal::kSeparator);
// The separator is required.
if (separatorPos == std::string::npos) {
return false;
}
// There must only be one separator.
if (code.find_first_of(internal::kSeparator) !=
code.find_last_of(internal::kSeparator)) {
return false;
}
// Is the separator the only character?
if (code.length() == 1) {
return false;
}
// Is the separator in an illegal position?
if (separatorPos > internal::kSeparatorPosition || separatorPos % 2 == 1) {
return false;
}
// We can have an even number of padding characters before the separator,
// but then it must be the final character.
std::size_t paddingStart = code.find_first_of(internal::kPaddingCharacter);
if (paddingStart != std::string::npos) {
// Short codes cannot have padding
if (separatorPos < internal::kSeparatorPosition) {
return false;
}
// The first padding character needs to be in an odd position.
if (paddingStart == 0 || paddingStart % 2) {
return false;
}
// Padded codes must not have anything after the separator
if (code.size() > separatorPos + 1) {
return false;
}
// Get from the first padding character to the separator
std::string paddingSection =
code.substr(paddingStart, internal::kSeparatorPosition - paddingStart);
paddingSection.erase(
std::remove(paddingSection.begin(), paddingSection.end(),
internal::kPaddingCharacter),
paddingSection.end());
// After removing padding characters, we mustn't have anything left.
if (!paddingSection.empty()) {
return false;
}
}
// If there are characters after the separator, make sure there isn't just
// one of them (not legal).
if (code.size() - code.find(internal::kSeparator) - 1 == 1) {
return false;
}
// Are there any invalid characters?
for (char c : code) {
if (c != internal::kSeparator && c != internal::kPaddingCharacter &&
get_alphabet_position(c) < 0) {
return false;
}
}
return true;
}
bool IsShort(const std::string &code) {
// Check it's valid.
if (!IsValid(code)) {
return false;
}
// If there are less characters than expected before the SEPARATOR.
if (code.find(internal::kSeparator) < internal::kSeparatorPosition) {
return true;
}
return false;
}
bool IsFull(const std::string &code) {
if (!IsValid(code)) {
return false;
}
// If it's short, it's not full.
if (IsShort(code)) {
return false;
}
// Work out what the first latitude character indicates for latitude.
size_t firstLatValue = get_alphabet_position(code.at(0));
firstLatValue *= internal::kEncodingBase;
if (firstLatValue >= internal::kLatitudeMaxDegrees * 2) {
// The code would decode to a latitude of >= 90 degrees.
return false;
}
if (code.size() > 1) {
// Work out what the first longitude character indicates for longitude.
size_t firstLngValue = get_alphabet_position(code.at(1));
firstLngValue *= internal::kEncodingBase;
if (firstLngValue >= internal::kLongitudeMaxDegrees * 2) {
// The code would decode to a longitude of >= 180 degrees.
return false;
}
}
return true;
}
size_t CodeLength(const std::string &code) {
std::string clean_code = clean_code_chars(code);
return clean_code.size();
}
} // namespace openlocationcode

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// The OpenLocationCode namespace provides a way of encoding between geographic
// coordinates and character strings that use a disambiguated character set.
// The aim is to provide a more convenient way for humans to handle geographic
// coordinates than latitude and longitude pairs.
//
// The codes can be easily read and remembered, and truncating codes converts
// them from a point to an area, meaning that where extreme accuracy is not
// required the codes can be shortened.
#ifndef LOCATION_OPENLOCATIONCODE_OPENLOCATIONCODE_H_
#define LOCATION_OPENLOCATIONCODE_OPENLOCATIONCODE_H_
#include <string>
#include "codearea.h"
namespace openlocationcode {
// Encodes a pair of coordinates and return an Open Location Code representing a
// rectangle that encloses the coordinates. The accuracy of the code is
// controlled by the code length.
//
// Returns an Open Location Code with code_length significant digits. The string
// returned may be one character longer if it includes a separator character
// for formatting.
std::string Encode(const LatLng &location, size_t code_length);
// Encodes a pair of coordinates and return an Open Location Code representing a
// rectangle that encloses the coordinates. The accuracy of the code is
// sufficient to represent a building such as a house, and is approximately
// 13x13 meters at Earth's equator.
std::string Encode(const LatLng &location);
// Decodes an Open Location Code and returns a rectangle that describes the area
// represented by the code.
CodeArea Decode(const std::string &code);
// Removes characters from the start of an OLC code.
// This uses a reference location to determine how many initial characters
// can be removed from the OLC code. The number of characters that can be
// removed depends on the distance between the code center and the reference
// location.
//
// The reference location must be within a safety factor of the maximum range.
// This ensures that the shortened code will be able to be recovered using
// slightly different locations.
//
// If the code isn't a valid full code or is padded, it cannot be shortened and
// the code is returned as-is.
std::string Shorten(const std::string &code, const LatLng &reference_location);
// Recovers the nearest matching code to a specified location.
// Given a short Open Location Code of between four and seven characters,
// this recovers the nearest matching full code to the specified location.
//
// If the code isn't a valid short code, it cannot be recovered and the code
// is returned as-is.
std::string RecoverNearest(const std::string &short_code,
const LatLng &reference_location);
// Returns the number of valid Open Location Code characters in a string. This
// excludes invalid characters and separators.
size_t CodeLength(const std::string &code);
// Determines if a code is valid and can be decoded.
// The empty string is a valid code, but whitespace included in a code is not
// valid.
bool IsValid(const std::string &code);
// Determines if a code is a valid short code.
bool IsShort(const std::string &code);
// Determines if a code is a valid full Open Location Code.
//
// Not all possible combinations of Open Location Code characters decode to
// valid latitude and longitude values. This checks that a code is valid
// and also that the latitude and longitude values are legal. If the prefix
// character is present, it must be the first character. If the separator
// character is present, it must be after four characters.
bool IsFull(const std::string &code);
namespace internal {
// The separator character is used to identify strings as OLC codes.
extern const char kSeparator;
// Provides the position of the separator.
extern const size_t kSeparatorPosition;
// Defines the maximum number of digits in a code (excluding separator). Codes
// with this length have a precision of less than 1e-10 cm at the equator.
extern const size_t kMaximumDigitCount;
// Padding is used when less precise codes are desired.
extern const char kPaddingCharacter;
// The alphabet of the codes.
extern const char kAlphabet[];
// Lookup table of the alphabet positions of characters 'C' through 'X',
// inclusive. A value of -1 means the character isn't part of the alphabet.
extern const int kPositionLUT['X' - 'C' + 1];
// The number base used for the encoding.
extern const size_t kEncodingBase;
// How many characters use the pair algorithm.
extern const size_t kPairCodeLength;
// Number of columns in the grid refinement method.
extern const size_t kGridColumns;
// Number of rows in the grid refinement method.
extern const size_t kGridRows;
// Gives the exponent used for the first pair.
extern const size_t kInitialExponent;
// Size of the initial grid in degrees. This is the size of the area represented
// by a 10 character code, and is kEncodingBase ^ (2 - kPairCodeLength / 2).
extern const double kGridSizeDegrees;
} // namespace internal
} // namespace openlocationcode
#endif // LOCATION_OPENLOCATIONCODE_OPENLOCATIONCODE_H_