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desmondyeoh/s2geometry.js

Created March 5, 2021 08:46
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s2geometry.js
/// S2 Geometry functions
// the regional scoreboard is based on a level 6 S2 Cell
// - https://docs.google.com/presentation/d/1Hl4KapfAENAOf4gv-pSngKwvS_jwNVHRPZTTDzXXn6Q/view?pli=1#slide=id.i22
// at the time of writing there's no actual API for the intel map to retrieve scoreboard data,
// but it's still useful to plot the score cells on the intel map
// the S2 geometry is based on projecting the earth sphere onto a cube, with some scaling of face coordinates to
// keep things close to approximate equal area for adjacent cells
// to convert a lat,lng into a cell id:
// - convert lat,lng to x,y,z
// - convert x,y,z into face,u,v
// - u,v scaled to s,t with quadratic formula
// - s,t converted to integer i,j offsets
// - i,j converted to a position along a Hubbert space-filling curve
// - combine face,position to get the cell id
//NOTE: compared to the google S2 geometry library, we vary from their code in the following ways
// - cell IDs: they combine face and the hilbert curve position into a single 64 bit number. this gives efficient space
// and speed. javascript doesn't have appropriate data types, and speed is not cricical, so we use
// as [face,[bitpair,bitpair,...]] instead
// - i,j: they always use 30 bits, adjusting as needed. we use 0 to (1<<level)-1 instead
// (so GetSizeIJ for a cell is always 1)
/**
* wasm optimizations, to do native i64 multiplication and divide
*/
var wasm = null;
try {
wasm = new WebAssembly.Instance(new WebAssembly.Module(new Uint8Array([
0, 97, 115, 109, 1, 0, 0, 0, 1, 13, 2, 96, 0, 1, 127, 96, 4, 127, 127, 127, 127, 1, 127, 3, 7, 6, 0, 1, 1, 1, 1, 1, 6, 6, 1, 127, 1, 65, 0, 11, 7, 50, 6, 3, 109, 117, 108, 0, 1, 5, 100, 105, 118, 95, 115, 0, 2, 5, 100, 105, 118, 95, 117, 0, 3, 5, 114, 101, 109, 95, 115, 0, 4, 5, 114, 101, 109, 95, 117, 0, 5, 8, 103, 101, 116, 95, 104, 105, 103, 104, 0, 0, 10, 191, 1, 6, 4, 0, 35, 0, 11, 36, 1, 1, 126, 32, 0, 173, 32, 1, 173, 66, 32, 134, 132, 32, 2, 173, 32, 3, 173, 66, 32, 134, 132, 126, 34, 4, 66, 32, 135, 167, 36, 0, 32, 4, 167, 11, 36, 1, 1, 126, 32, 0, 173, 32, 1, 173, 66, 32, 134, 132, 32, 2, 173, 32, 3, 173, 66, 32, 134, 132, 127, 34, 4, 66, 32, 135, 167, 36, 0, 32, 4, 167, 11, 36, 1, 1, 126, 32, 0, 173, 32, 1, 173, 66, 32, 134, 132, 32, 2, 173, 32, 3, 173, 66, 32, 134, 132, 128, 34, 4, 66, 32, 135, 167, 36, 0, 32, 4, 167, 11, 36, 1, 1, 126, 32, 0, 173, 32, 1, 173, 66, 32, 134, 132, 32, 2, 173, 32, 3, 173, 66, 32, 134, 132, 129, 34, 4, 66, 32, 135, 167, 36, 0, 32, 4, 167, 11, 36, 1, 1, 126, 32, 0, 173, 32, 1, 173, 66, 32, 134, 132, 32, 2, 173, 32, 3, 173, 66, 32, 134, 132, 130, 34, 4, 66, 32, 135, 167, 36, 0, 32, 4, 167, 11
])), {}).exports;
} catch (e) {
// no wasm support :(
}
/**
* Constructs a 64 bit two's-complement integer, given its low and high 32 bit values as *signed* integers.
* See the from* functions below for more convenient ways of constructing Longs.
* @exports Long
* @class A Long class for representing a 64 bit two's-complement integer value.
* @param {number} low The low (signed) 32 bits of the long
* @param {number} high The high (signed) 32 bits of the long
* @param {boolean=} unsigned Whether unsigned or not, defaults to signed
* @constructor
*/
function Long(low, high, unsigned) {
/**
* The low 32 bits as a signed value.
* @type {number}
*/
this.low = low | 0;
/**
* The high 32 bits as a signed value.
* @type {number}
*/
this.high = high | 0;
/**
* Whether unsigned or not.
* @type {boolean}
*/
this.unsigned = !!unsigned;
}
// The internal representation of a long is the two given signed, 32-bit values.
// We use 32-bit pieces because these are the size of integers on which
// Javascript performs bit-operations. For operations like addition and
// multiplication, we split each number into 16 bit pieces, which can easily be
// multiplied within Javascript's floating-point representation without overflow
// or change in sign.
//
// In the algorithms below, we frequently reduce the negative case to the
// positive case by negating the input(s) and then post-processing the result.
// Note that we must ALWAYS check specially whether those values are MIN_VALUE
// (-2^63) because -MIN_VALUE == MIN_VALUE (since 2^63 cannot be represented as
// a positive number, it overflows back into a negative). Not handling this
// case would often result in infinite recursion.
//
// Common constant values ZERO, ONE, NEG_ONE, etc. are defined below the from*
// methods on which they depend.
/**
* An indicator used to reliably determine if an object is a Long or not.
* @type {boolean}
* @const
* @private
*/
Long.prototype.__isLong__;
Object.defineProperty(Long.prototype, "__isLong__", { value: true });
/**
* @function
* @param {*} obj Object
* @returns {boolean}
* @inner
*/
function isLong(obj) {
return (obj && obj["__isLong__"]) === true;
}
/**
* Tests if the specified object is a Long.
* @function
* @param {*} obj Object
* @returns {boolean}
*/
Long.isLong = isLong;
/**
* A cache of the Long representations of small integer values.
* @type {!Object}
* @inner
*/
var INT_CACHE = {};
/**
* A cache of the Long representations of small unsigned integer values.
* @type {!Object}
* @inner
*/
var UINT_CACHE = {};
/**
* @param {number} value
* @param {boolean=} unsigned
* @returns {!Long}
* @inner
*/
function fromInt(value, unsigned) {
var obj, cachedObj, cache;
if (unsigned) {
value >>>= 0;
if (cache = (0 <= value && value < 256)) {
cachedObj = UINT_CACHE[value];
if (cachedObj)
return cachedObj;
}
obj = fromBits(value, (value | 0) < 0 ? -1 : 0, true);
if (cache)
UINT_CACHE[value] = obj;
return obj;
} else {
value |= 0;
if (cache = (-128 <= value && value < 128)) {
cachedObj = INT_CACHE[value];
if (cachedObj)
return cachedObj;
}
obj = fromBits(value, value < 0 ? -1 : 0, false);
if (cache)
INT_CACHE[value] = obj;
return obj;
}
}
/**
* Returns a Long representing the given 32 bit integer value.
* @function
* @param {number} value The 32 bit integer in question
* @param {boolean=} unsigned Whether unsigned or not, defaults to signed
* @returns {!Long} The corresponding Long value
*/
Long.fromInt = fromInt;
/**
* @param {number} value
* @param {boolean=} unsigned
* @returns {!Long}
* @inner
*/
function fromNumber(value, unsigned) {
if (isNaN(value))
return unsigned ? UZERO : ZERO;
if (unsigned) {
if (value < 0)
return UZERO;
if (value >= TWO_PWR_64_DBL)
return MAX_UNSIGNED_VALUE;
} else {
if (value <= -TWO_PWR_63_DBL)
return MIN_VALUE;
if (value + 1 >= TWO_PWR_63_DBL)
return MAX_VALUE;
}
if (value < 0)
return fromNumber(-value, unsigned).neg();
return fromBits((value % TWO_PWR_32_DBL) | 0, (value / TWO_PWR_32_DBL) | 0, unsigned);
}
/**
* Returns a Long representing the given value, provided that it is a finite number. Otherwise, zero is returned.
* @function
* @param {number} value The number in question
* @param {boolean=} unsigned Whether unsigned or not, defaults to signed
* @returns {!Long} The corresponding Long value
*/
Long.fromNumber = fromNumber;
/**
* @param {number} lowBits
* @param {number} highBits
* @param {boolean=} unsigned
* @returns {!Long}
* @inner
*/
function fromBits(lowBits, highBits, unsigned) {
return new Long(lowBits, highBits, unsigned);
}
/**
* Returns a Long representing the 64 bit integer that comes by concatenating the given low and high bits. Each is
* assumed to use 32 bits.
* @function
* @param {number} lowBits The low 32 bits
* @param {number} highBits The high 32 bits
* @param {boolean=} unsigned Whether unsigned or not, defaults to signed
* @returns {!Long} The corresponding Long value
*/
Long.fromBits = fromBits;
/**
* @function
* @param {number} base
* @param {number} exponent
* @returns {number}
* @inner
*/
var pow_dbl = Math.pow; // Used 4 times (4*8 to 15+4)
/**
* @param {string} str
* @param {(boolean|number)=} unsigned
* @param {number=} radix
* @returns {!Long}
* @inner
*/
function fromString(str, unsigned, radix) {
if (str.length === 0)
throw Error('empty string');
if (str === "NaN" || str === "Infinity" || str === "+Infinity" || str === "-Infinity")
return ZERO;
if (typeof unsigned === 'number') {
// For goog.math.long compatibility
radix = unsigned,
unsigned = false;
} else {
unsigned = !! unsigned;
}
radix = radix || 10;
if (radix < 2 || 36 < radix)
throw RangeError('radix');
var p;
if ((p = str.indexOf('-')) > 0)
throw Error('interior hyphen');
else if (p === 0) {
return fromString(str.substring(1), unsigned, radix).neg();
}
// Do several (8) digits each time through the loop, so as to
// minimize the calls to the very expensive emulated div.
var radixToPower = fromNumber(pow_dbl(radix, 8));
var result = ZERO;
for (var i = 0; i < str.length; i += 8) {
var size = Math.min(8, str.length - i),
value = parseInt(str.substring(i, i + size), radix);
if (size < 8) {
var power = fromNumber(pow_dbl(radix, size));
result = result.mul(power).add(fromNumber(value));
} else {
result = result.mul(radixToPower);
result = result.add(fromNumber(value));
}
}
result.unsigned = unsigned;
return result;
}
/**
* Returns a Long representation of the given string, written using the specified radix.
* @function
* @param {string} str The textual representation of the Long
* @param {(boolean|number)=} unsigned Whether unsigned or not, defaults to signed
* @param {number=} radix The radix in which the text is written (2-36), defaults to 10
* @returns {!Long} The corresponding Long value
*/
Long.fromString = fromString;
/**
* @function
* @param {!Long|number|string|!{low: number, high: number, unsigned: boolean}} val
* @param {boolean=} unsigned
* @returns {!Long}
* @inner
*/
function fromValue(val, unsigned) {
if (typeof val === 'number')
return fromNumber(val, unsigned);
if (typeof val === 'string')
return fromString(val, unsigned);
// Throws for non-objects, converts non-instanceof Long:
return fromBits(val.low, val.high, typeof unsigned === 'boolean' ? unsigned : val.unsigned);
}
/**
* Converts the specified value to a Long using the appropriate from* function for its type.
* @function
* @param {!Long|number|string|!{low: number, high: number, unsigned: boolean}} val Value
* @param {boolean=} unsigned Whether unsigned or not, defaults to signed
* @returns {!Long}
*/
Long.fromValue = fromValue;
// NOTE: the compiler should inline these constant values below and then remove these variables, so there should be
// no runtime penalty for these.
/**
* @type {number}
* @const
* @inner
*/
var TWO_PWR_16_DBL = 1 << 16;
/**
* @type {number}
* @const
* @inner
*/
var TWO_PWR_24_DBL = 1 << 24;
/**
* @type {number}
* @const
* @inner
*/
var TWO_PWR_32_DBL = TWO_PWR_16_DBL * TWO_PWR_16_DBL;
/**
* @type {number}
* @const
* @inner
*/
var TWO_PWR_64_DBL = TWO_PWR_32_DBL * TWO_PWR_32_DBL;
/**
* @type {number}
* @const
* @inner
*/
var TWO_PWR_63_DBL = TWO_PWR_64_DBL / 2;
/**
* @type {!Long}
* @const
* @inner
*/
var TWO_PWR_24 = fromInt(TWO_PWR_24_DBL);
/**
* @type {!Long}
* @inner
*/
var ZERO = fromInt(0);
/**
* Signed zero.
* @type {!Long}
*/
Long.ZERO = ZERO;
/**
* @type {!Long}
* @inner
*/
var UZERO = fromInt(0, true);
/**
* Unsigned zero.
* @type {!Long}
*/
Long.UZERO = UZERO;
/**
* @type {!Long}
* @inner
*/
var ONE = fromInt(1);
/**
* Signed one.
* @type {!Long}
*/
Long.ONE = ONE;
/**
* @type {!Long}
* @inner
*/
var UONE = fromInt(1, true);
/**
* Unsigned one.
* @type {!Long}
*/
Long.UONE = UONE;
/**
* @type {!Long}
* @inner
*/
var NEG_ONE = fromInt(-1);
/**
* Signed negative one.
* @type {!Long}
*/
Long.NEG_ONE = NEG_ONE;
/**
* @type {!Long}
* @inner
*/
var MAX_VALUE = fromBits(0xFFFFFFFF|0, 0x7FFFFFFF|0, false);
/**
* Maximum signed value.
* @type {!Long}
*/
Long.MAX_VALUE = MAX_VALUE;
/**
* @type {!Long}
* @inner
*/
var MAX_UNSIGNED_VALUE = fromBits(0xFFFFFFFF|0, 0xFFFFFFFF|0, true);
/**
* Maximum unsigned value.
* @type {!Long}
*/
Long.MAX_UNSIGNED_VALUE = MAX_UNSIGNED_VALUE;
/**
* @type {!Long}
* @inner
*/
var MIN_VALUE = fromBits(0, 0x80000000|0, false);
/**
* Minimum signed value.
* @type {!Long}
*/
Long.MIN_VALUE = MIN_VALUE;
/**
* @alias Long.prototype
* @inner
*/
var LongPrototype = Long.prototype;
/**
* Converts the Long to a 32 bit integer, assuming it is a 32 bit integer.
* @returns {number}
*/
LongPrototype.toInt = function toInt() {
return this.unsigned ? this.low >>> 0 : this.low;
};
/**
* Converts the Long to a the nearest floating-point representation of this value (double, 53 bit mantissa).
* @returns {number}
*/
LongPrototype.toNumber = function toNumber() {
if (this.unsigned)
return ((this.high >>> 0) * TWO_PWR_32_DBL) + (this.low >>> 0);
return this.high * TWO_PWR_32_DBL + (this.low >>> 0);
};
/**
* Converts the Long to a string written in the specified radix.
* @param {number=} radix Radix (2-36), defaults to 10
* @returns {string}
* @override
* @throws {RangeError} If `radix` is out of range
*/
LongPrototype.toString = function toString(radix) {
radix = radix || 10;
if (radix < 2 || 36 < radix)
throw RangeError('radix');
if (this.isZero())
return '0';
if (this.isNegative()) { // Unsigned Longs are never negative
if (this.eq(MIN_VALUE)) {
// We need to change the Long value before it can be negated, so we remove
// the bottom-most digit in this base and then recurse to do the rest.
var radixLong = fromNumber(radix),
div = this.div(radixLong),
rem1 = div.mul(radixLong).sub(this);
return div.toString(radix) + rem1.toInt().toString(radix);
} else
return '-' + this.neg().toString(radix);
}
// Do several (6) digits each time through the loop, so as to
// minimize the calls to the very expensive emulated div.
var radixToPower = fromNumber(pow_dbl(radix, 6), this.unsigned),
rem = this;
var result = '';
while (true) {
var remDiv = rem.div(radixToPower),
intval = rem.sub(remDiv.mul(radixToPower)).toInt() >>> 0,
digits = intval.toString(radix);
rem = remDiv;
if (rem.isZero())
return digits + result;
else {
while (digits.length < 6)
digits = '0' + digits;
result = '' + digits + result;
}
}
};
/**
* Gets the high 32 bits as a signed integer.
* @returns {number} Signed high bits
*/
LongPrototype.getHighBits = function getHighBits() {
return this.high;
};
/**
* Gets the high 32 bits as an unsigned integer.
* @returns {number} Unsigned high bits
*/
LongPrototype.getHighBitsUnsigned = function getHighBitsUnsigned() {
return this.high >>> 0;
};
/**
* Gets the low 32 bits as a signed integer.
* @returns {number} Signed low bits
*/
LongPrototype.getLowBits = function getLowBits() {
return this.low;
};
/**
* Gets the low 32 bits as an unsigned integer.
* @returns {number} Unsigned low bits
*/
LongPrototype.getLowBitsUnsigned = function getLowBitsUnsigned() {
return this.low >>> 0;
};
/**
* Gets the number of bits needed to represent the absolute value of this Long.
* @returns {number}
*/
LongPrototype.getNumBitsAbs = function getNumBitsAbs() {
if (this.isNegative()) // Unsigned Longs are never negative
return this.eq(MIN_VALUE) ? 64 : this.neg().getNumBitsAbs();
var val = this.high != 0 ? this.high : this.low;
for (var bit = 31; bit > 0; bit--)
if ((val & (1 << bit)) != 0)
break;
return this.high != 0 ? bit + 33 : bit + 1;
};
/**
* Tests if this Long's value equals zero.
* @returns {boolean}
*/
LongPrototype.isZero = function isZero() {
return this.high === 0 && this.low === 0;
};
/**
* Tests if this Long's value equals zero. This is an alias of {@link Long#isZero}.
* @returns {boolean}
*/
LongPrototype.eqz = LongPrototype.isZero;
/**
* Tests if this Long's value is negative.
* @returns {boolean}
*/
LongPrototype.isNegative = function isNegative() {
return !this.unsigned && this.high < 0;
};
/**
* Tests if this Long's value is positive.
* @returns {boolean}
*/
LongPrototype.isPositive = function isPositive() {
return this.unsigned || this.high >= 0;
};
/**
* Tests if this Long's value is odd.
* @returns {boolean}
*/
LongPrototype.isOdd = function isOdd() {
return (this.low & 1) === 1;
};
/**
* Tests if this Long's value is even.
* @returns {boolean}
*/
LongPrototype.isEven = function isEven() {
return (this.low & 1) === 0;
};
/**
* Tests if this Long's value equals the specified's.
* @param {!Long|number|string} other Other value
* @returns {boolean}
*/
LongPrototype.equals = function equals(other) {
if (!isLong(other))
other = fromValue(other);
if (this.unsigned !== other.unsigned && (this.high >>> 31) === 1 && (other.high >>> 31) === 1)
return false;
return this.high === other.high && this.low === other.low;
};
/**
* Tests if this Long's value equals the specified's. This is an alias of {@link Long#equals}.
* @function
* @param {!Long|number|string} other Other value
* @returns {boolean}
*/
LongPrototype.eq = LongPrototype.equals;
/**
* Tests if this Long's value differs from the specified's.
* @param {!Long|number|string} other Other value
* @returns {boolean}
*/
LongPrototype.notEquals = function notEquals(other) {
return !this.eq(/* validates */ other);
};
/**
* Tests if this Long's value differs from the specified's. This is an alias of {@link Long#notEquals}.
* @function
* @param {!Long|number|string} other Other value
* @returns {boolean}
*/
LongPrototype.neq = LongPrototype.notEquals;
/**
* Tests if this Long's value differs from the specified's. This is an alias of {@link Long#notEquals}.
* @function
* @param {!Long|number|string} other Other value
* @returns {boolean}
*/
LongPrototype.ne = LongPrototype.notEquals;
/**
* Tests if this Long's value is less than the specified's.
* @param {!Long|number|string} other Other value
* @returns {boolean}
*/
LongPrototype.lessThan = function lessThan(other) {
return this.comp(/* validates */ other) < 0;
};
/**
* Tests if this Long's value is less than the specified's. This is an alias of {@link Long#lessThan}.
* @function
* @param {!Long|number|string} other Other value
* @returns {boolean}
*/
LongPrototype.lt = LongPrototype.lessThan;
/**
* Tests if this Long's value is less than or equal the specified's.
* @param {!Long|number|string} other Other value
* @returns {boolean}
*/
LongPrototype.lessThanOrEqual = function lessThanOrEqual(other) {
return this.comp(/* validates */ other) <= 0;
};
/**
* Tests if this Long's value is less than or equal the specified's. This is an alias of {@link Long#lessThanOrEqual}.
* @function
* @param {!Long|number|string} other Other value
* @returns {boolean}
*/
LongPrototype.lte = LongPrototype.lessThanOrEqual;
/**
* Tests if this Long's value is less than or equal the specified's. This is an alias of {@link Long#lessThanOrEqual}.
* @function
* @param {!Long|number|string} other Other value
* @returns {boolean}
*/
LongPrototype.le = LongPrototype.lessThanOrEqual;
/**
* Tests if this Long's value is greater than the specified's.
* @param {!Long|number|string} other Other value
* @returns {boolean}
*/
LongPrototype.greaterThan = function greaterThan(other) {
return this.comp(/* validates */ other) > 0;
};
/**
* Tests if this Long's value is greater than the specified's. This is an alias of {@link Long#greaterThan}.
* @function
* @param {!Long|number|string} other Other value
* @returns {boolean}
*/
LongPrototype.gt = LongPrototype.greaterThan;
/**
* Tests if this Long's value is greater than or equal the specified's.
* @param {!Long|number|string} other Other value
* @returns {boolean}
*/
LongPrototype.greaterThanOrEqual = function greaterThanOrEqual(other) {
return this.comp(/* validates */ other) >= 0;
};
/**
* Tests if this Long's value is greater than or equal the specified's. This is an alias of {@link Long#greaterThanOrEqual}.
* @function
* @param {!Long|number|string} other Other value
* @returns {boolean}
*/
LongPrototype.gte = LongPrototype.greaterThanOrEqual;
/**
* Tests if this Long's value is greater than or equal the specified's. This is an alias of {@link Long#greaterThanOrEqual}.
* @function
* @param {!Long|number|string} other Other value
* @returns {boolean}
*/
LongPrototype.ge = LongPrototype.greaterThanOrEqual;
/**
* Compares this Long's value with the specified's.
* @param {!Long|number|string} other Other value
* @returns {number} 0 if they are the same, 1 if the this is greater and -1
* if the given one is greater
*/
LongPrototype.compare = function compare(other) {
if (!isLong(other))
other = fromValue(other);
if (this.eq(other))
return 0;
var thisNeg = this.isNegative(),
otherNeg = other.isNegative();
if (thisNeg && !otherNeg)
return -1;
if (!thisNeg && otherNeg)
return 1;
// At this point the sign bits are the same
if (!this.unsigned)
return this.sub(other).isNegative() ? -1 : 1;
// Both are positive if at least one is unsigned
return (other.high >>> 0) > (this.high >>> 0) || (other.high === this.high && (other.low >>> 0) > (this.low >>> 0)) ? -1 : 1;
};
/**
* Compares this Long's value with the specified's. This is an alias of {@link Long#compare}.
* @function
* @param {!Long|number|string} other Other value
* @returns {number} 0 if they are the same, 1 if the this is greater and -1
* if the given one is greater
*/
LongPrototype.comp = LongPrototype.compare;
/**
* Negates this Long's value.
* @returns {!Long} Negated Long
*/
LongPrototype.negate = function negate() {
if (!this.unsigned && this.eq(MIN_VALUE))
return MIN_VALUE;
return this.not().add(ONE);
};
/**
* Negates this Long's value. This is an alias of {@link Long#negate}.
* @function
* @returns {!Long} Negated Long
*/
LongPrototype.neg = LongPrototype.negate;
/**
* Returns the sum of this and the specified Long.
* @param {!Long|number|string} addend Addend
* @returns {!Long} Sum
*/
LongPrototype.add = function add(addend) {
if (!isLong(addend))
addend = fromValue(addend);
// Divide each number into 4 chunks of 16 bits, and then sum the chunks.
var a48 = this.high >>> 16;
var a32 = this.high & 0xFFFF;
var a16 = this.low >>> 16;
var a00 = this.low & 0xFFFF;
var b48 = addend.high >>> 16;
var b32 = addend.high & 0xFFFF;
var b16 = addend.low >>> 16;
var b00 = addend.low & 0xFFFF;
var c48 = 0, c32 = 0, c16 = 0, c00 = 0;
c00 += a00 + b00;
c16 += c00 >>> 16;
c00 &= 0xFFFF;
c16 += a16 + b16;
c32 += c16 >>> 16;
c16 &= 0xFFFF;
c32 += a32 + b32;
c48 += c32 >>> 16;
c32 &= 0xFFFF;
c48 += a48 + b48;
c48 &= 0xFFFF;
return fromBits((c16 << 16) | c00, (c48 << 16) | c32, this.unsigned);
};
/**
* Returns the difference of this and the specified Long.
* @param {!Long|number|string} subtrahend Subtrahend
* @returns {!Long} Difference
*/
LongPrototype.subtract = function subtract(subtrahend) {
if (!isLong(subtrahend))
subtrahend = fromValue(subtrahend);
return this.add(subtrahend.neg());
};
/**
* Returns the difference of this and the specified Long. This is an alias of {@link Long#subtract}.
* @function
* @param {!Long|number|string} subtrahend Subtrahend
* @returns {!Long} Difference
*/
LongPrototype.sub = LongPrototype.subtract;
/**
* Returns the product of this and the specified Long.
* @param {!Long|number|string} multiplier Multiplier
* @returns {!Long} Product
*/
LongPrototype.multiply = function multiply(multiplier) {
if (this.isZero())
return ZERO;
if (!isLong(multiplier))
multiplier = fromValue(multiplier);
// use wasm support if present
if (wasm) {
var low = wasm.mul(this.low,
this.high,
multiplier.low,
multiplier.high);
return fromBits(low, wasm.get_high(), this.unsigned);
}
if (multiplier.isZero())
return ZERO;
if (this.eq(MIN_VALUE))
return multiplier.isOdd() ? MIN_VALUE : ZERO;
if (multiplier.eq(MIN_VALUE))
return this.isOdd() ? MIN_VALUE : ZERO;
if (this.isNegative()) {
if (multiplier.isNegative())
return this.neg().mul(multiplier.neg());
else
return this.neg().mul(multiplier).neg();
} else if (multiplier.isNegative())
return this.mul(multiplier.neg()).neg();
// If both longs are small, use float multiplication
if (this.lt(TWO_PWR_24) && multiplier.lt(TWO_PWR_24))
return fromNumber(this.toNumber() * multiplier.toNumber(), this.unsigned);
// Divide each long into 4 chunks of 16 bits, and then add up 4x4 products.
// We can skip products that would overflow.
var a48 = this.high >>> 16;
var a32 = this.high & 0xFFFF;
var a16 = this.low >>> 16;
var a00 = this.low & 0xFFFF;
var b48 = multiplier.high >>> 16;
var b32 = multiplier.high & 0xFFFF;
var b16 = multiplier.low >>> 16;
var b00 = multiplier.low & 0xFFFF;
var c48 = 0, c32 = 0, c16 = 0, c00 = 0;
c00 += a00 * b00;
c16 += c00 >>> 16;
c00 &= 0xFFFF;
c16 += a16 * b00;
c32 += c16 >>> 16;
c16 &= 0xFFFF;
c16 += a00 * b16;
c32 += c16 >>> 16;
c16 &= 0xFFFF;
c32 += a32 * b00;
c48 += c32 >>> 16;
c32 &= 0xFFFF;
c32 += a16 * b16;
c48 += c32 >>> 16;
c32 &= 0xFFFF;
c32 += a00 * b32;
c48 += c32 >>> 16;
c32 &= 0xFFFF;
c48 += a48 * b00 + a32 * b16 + a16 * b32 + a00 * b48;
c48 &= 0xFFFF;
return fromBits((c16 << 16) | c00, (c48 << 16) | c32, this.unsigned);
};
/**
* Returns the product of this and the specified Long. This is an alias of {@link Long#multiply}.
* @function
* @param {!Long|number|string} multiplier Multiplier
* @returns {!Long} Product
*/
LongPrototype.mul = LongPrototype.multiply;
/**
* Returns this Long divided by the specified. The result is signed if this Long is signed or
* unsigned if this Long is unsigned.
* @param {!Long|number|string} divisor Divisor
* @returns {!Long} Quotient
*/
LongPrototype.divide = function divide(divisor) {
if (!isLong(divisor))
divisor = fromValue(divisor);
if (divisor.isZero())
throw Error('division by zero');
// use wasm support if present
if (wasm) {
// guard against signed division overflow: the largest
// negative number / -1 would be 1 larger than the largest
// positive number, due to two's complement.
if (!this.unsigned &&
this.high === -0x80000000 &&
divisor.low === -1 && divisor.high === -1) {
// be consistent with non-wasm code path
return this;
}
var low = (this.unsigned ? wasm.div_u : wasm.div_s)(
this.low,
this.high,
divisor.low,
divisor.high
);
return fromBits(low, wasm.get_high(), this.unsigned);
}
if (this.isZero())
return this.unsigned ? UZERO : ZERO;
var approx, rem, res;
if (!this.unsigned) {
// This section is only relevant for signed longs and is derived from the
// closure library as a whole.
if (this.eq(MIN_VALUE)) {
if (divisor.eq(ONE) || divisor.eq(NEG_ONE))
return MIN_VALUE; // recall that -MIN_VALUE == MIN_VALUE
else if (divisor.eq(MIN_VALUE))
return ONE;
else {
// At this point, we have |other| >= 2, so |this/other| < |MIN_VALUE|.
var halfThis = this.shr(1);
approx = halfThis.div(divisor).shl(1);
if (approx.eq(ZERO)) {
return divisor.isNegative() ? ONE : NEG_ONE;
} else {
rem = this.sub(divisor.mul(approx));
res = approx.add(rem.div(divisor));
return res;
}
}
} else if (divisor.eq(MIN_VALUE))
return this.unsigned ? UZERO : ZERO;
if (this.isNegative()) {
if (divisor.isNegative())
return this.neg().div(divisor.neg());
return this.neg().div(divisor).neg();
} else if (divisor.isNegative())
return this.div(divisor.neg()).neg();
res = ZERO;
} else {
// The algorithm below has not been made for unsigned longs. It's therefore
// required to take special care of the MSB prior to running it.
if (!divisor.unsigned)
divisor = divisor.toUnsigned();
if (divisor.gt(this))
return UZERO;
if (divisor.gt(this.shru(1))) // 15 >>> 1 = 7 ; with divisor = 8 ; true
return UONE;
res = UZERO;
}
// Repeat the following until the remainder is less than other: find a
// floating-point that approximates remainder / other *from below*, add this
// into the result, and subtract it from the remainder. It is critical that
// the approximate value is less than or equal to the real value so that the
// remainder never becomes negative.
rem = this;
while (rem.gte(divisor)) {
// Approximate the result of division. This may be a little greater or
// smaller than the actual value.
approx = Math.max(1, Math.floor(rem.toNumber() / divisor.toNumber()));
// We will tweak the approximate result by changing it in the 48-th digit or
// the smallest non-fractional digit, whichever is larger.
var log2 = Math.ceil(Math.log(approx) / Math.LN2),
delta = (log2 <= 48) ? 1 : pow_dbl(2, log2 - 48),
// Decrease the approximation until it is smaller than the remainder. Note
// that if it is too large, the product overflows and is negative.
approxRes = fromNumber(approx),
approxRem = approxRes.mul(divisor);
while (approxRem.isNegative() || approxRem.gt(rem)) {
approx -= delta;
approxRes = fromNumber(approx, this.unsigned);
approxRem = approxRes.mul(divisor);
}
// We know the answer can't be zero... and actually, zero would cause
// infinite recursion since we would make no progress.
if (approxRes.isZero())
approxRes = ONE;
res = res.add(approxRes);
rem = rem.sub(approxRem);
}
return res;
};
/**
* Returns this Long divided by the specified. This is an alias of {@link Long#divide}.
* @function
* @param {!Long|number|string} divisor Divisor
* @returns {!Long} Quotient
*/
LongPrototype.div = LongPrototype.divide;
/**
* Returns this Long modulo the specified.
* @param {!Long|number|string} divisor Divisor
* @returns {!Long} Remainder
*/
LongPrototype.modulo = function modulo(divisor) {
if (!isLong(divisor))
divisor = fromValue(divisor);
// use wasm support if present
if (wasm) {
var low = (this.unsigned ? wasm.rem_u : wasm.rem_s)(
this.low,
this.high,
divisor.low,
divisor.high
);
return fromBits(low, wasm.get_high(), this.unsigned);
}
return this.sub(this.div(divisor).mul(divisor));
};
/**
* Returns this Long modulo the specified. This is an alias of {@link Long#modulo}.
* @function
* @param {!Long|number|string} divisor Divisor
* @returns {!Long} Remainder
*/
LongPrototype.mod = LongPrototype.modulo;
/**
* Returns this Long modulo the specified. This is an alias of {@link Long#modulo}.
* @function
* @param {!Long|number|string} divisor Divisor
* @returns {!Long} Remainder
*/
LongPrototype.rem = LongPrototype.modulo;
/**
* Returns the bitwise NOT of this Long.
* @returns {!Long}
*/
LongPrototype.not = function not() {
return fromBits(~this.low, ~this.high, this.unsigned);
};
/**
* Returns the bitwise AND of this Long and the specified.
* @param {!Long|number|string} other Other Long
* @returns {!Long}
*/
LongPrototype.and = function and(other) {
if (!isLong(other))
other = fromValue(other);
return fromBits(this.low & other.low, this.high & other.high, this.unsigned);
};
/**
* Returns the bitwise OR of this Long and the specified.
* @param {!Long|number|string} other Other Long
* @returns {!Long}
*/
LongPrototype.or = function or(other) {
if (!isLong(other))
other = fromValue(other);
return fromBits(this.low | other.low, this.high | other.high, this.unsigned);
};
/**
* Returns the bitwise XOR of this Long and the given one.
* @param {!Long|number|string} other Other Long
* @returns {!Long}
*/
LongPrototype.xor = function xor(other) {
if (!isLong(other))
other = fromValue(other);
return fromBits(this.low ^ other.low, this.high ^ other.high, this.unsigned);
};
/**
* Returns this Long with bits shifted to the left by the given amount.
* @param {number|!Long} numBits Number of bits
* @returns {!Long} Shifted Long
*/
LongPrototype.shiftLeft = function shiftLeft(numBits) {
if (isLong(numBits))
numBits = numBits.toInt();
if ((numBits &= 63) === 0)
return this;
else if (numBits < 32)
return fromBits(this.low << numBits, (this.high << numBits) | (this.low >>> (32 - numBits)), this.unsigned);
else
return fromBits(0, this.low << (numBits - 32), this.unsigned);
};
/**
* Returns this Long with bits shifted to the left by the given amount. This is an alias of {@link Long#shiftLeft}.
* @function
* @param {number|!Long} numBits Number of bits
* @returns {!Long} Shifted Long
*/
LongPrototype.shl = LongPrototype.shiftLeft;
/**
* Returns this Long with bits arithmetically shifted to the right by the given amount.
* @param {number|!Long} numBits Number of bits
* @returns {!Long} Shifted Long
*/
LongPrototype.shiftRight = function shiftRight(numBits) {
if (isLong(numBits))
numBits = numBits.toInt();
if ((numBits &= 63) === 0)
return this;
else if (numBits < 32)
return fromBits((this.low >>> numBits) | (this.high << (32 - numBits)), this.high >> numBits, this.unsigned);
else
return fromBits(this.high >> (numBits - 32), this.high >= 0 ? 0 : -1, this.unsigned);
};
/**
* Returns this Long with bits arithmetically shifted to the right by the given amount. This is an alias of {@link Long#shiftRight}.
* @function
* @param {number|!Long} numBits Number of bits
* @returns {!Long} Shifted Long
*/
LongPrototype.shr = LongPrototype.shiftRight;
/**
* Returns this Long with bits logically shifted to the right by the given amount.
* @param {number|!Long} numBits Number of bits
* @returns {!Long} Shifted Long
*/
LongPrototype.shiftRightUnsigned = function shiftRightUnsigned(numBits) {
if (isLong(numBits))
numBits = numBits.toInt();
numBits &= 63;
if (numBits === 0)
return this;
else {
var high = this.high;
if (numBits < 32) {
var low = this.low;
return fromBits((low >>> numBits) | (high << (32 - numBits)), high >>> numBits, this.unsigned);
} else if (numBits === 32)
return fromBits(high, 0, this.unsigned);
else
return fromBits(high >>> (numBits - 32), 0, this.unsigned);
}
};
/**
* Returns this Long with bits logically shifted to the right by the given amount. This is an alias of {@link Long#shiftRightUnsigned}.
* @function
* @param {number|!Long} numBits Number of bits
* @returns {!Long} Shifted Long
*/
LongPrototype.shru = LongPrototype.shiftRightUnsigned;
/**
* Returns this Long with bits logically shifted to the right by the given amount. This is an alias of {@link Long#shiftRightUnsigned}.
* @function
* @param {number|!Long} numBits Number of bits
* @returns {!Long} Shifted Long
*/
LongPrototype.shr_u = LongPrototype.shiftRightUnsigned;
/**
* Converts this Long to signed.
* @returns {!Long} Signed long
*/
LongPrototype.toSigned = function toSigned() {
if (!this.unsigned)
return this;
return fromBits(this.low, this.high, false);
};
/**
* Converts this Long to unsigned.
* @returns {!Long} Unsigned long
*/
LongPrototype.toUnsigned = function toUnsigned() {
if (this.unsigned)
return this;
return fromBits(this.low, this.high, true);
};
/**
* Converts this Long to its byte representation.
* @param {boolean=} le Whether little or big endian, defaults to big endian
* @returns {!Array.<number>} Byte representation
*/
LongPrototype.toBytes = function toBytes(le) {
return le ? this.toBytesLE() : this.toBytesBE();
};
/**
* Converts this Long to its little endian byte representation.
* @returns {!Array.<number>} Little endian byte representation
*/
LongPrototype.toBytesLE = function toBytesLE() {
var hi = this.high,
lo = this.low;
return [
lo & 0xff,
lo >>> 8 & 0xff,
lo >>> 16 & 0xff,
lo >>> 24 ,
hi & 0xff,
hi >>> 8 & 0xff,
hi >>> 16 & 0xff,
hi >>> 24
];
};
/**
* Converts this Long to its big endian byte representation.
* @returns {!Array.<number>} Big endian byte representation
*/
LongPrototype.toBytesBE = function toBytesBE() {
var hi = this.high,
lo = this.low;
return [
hi >>> 24 ,
hi >>> 16 & 0xff,
hi >>> 8 & 0xff,
hi & 0xff,
lo >>> 24 ,
lo >>> 16 & 0xff,
lo >>> 8 & 0xff,
lo & 0xff
];
};
/**
* Creates a Long from its byte representation.
* @param {!Array.<number>} bytes Byte representation
* @param {boolean=} unsigned Whether unsigned or not, defaults to signed
* @param {boolean=} le Whether little or big endian, defaults to big endian
* @returns {Long} The corresponding Long value
*/
Long.fromBytes = function fromBytes(bytes, unsigned, le) {
return le ? Long.fromBytesLE(bytes, unsigned) : Long.fromBytesBE(bytes, unsigned);
};
/**
* Creates a Long from its little endian byte representation.
* @param {!Array.<number>} bytes Little endian byte representation
* @param {boolean=} unsigned Whether unsigned or not, defaults to signed
* @returns {Long} The corresponding Long value
*/
Long.fromBytesLE = function fromBytesLE(bytes, unsigned) {
return new Long(
bytes[0] |
bytes[1] << 8 |
bytes[2] << 16 |
bytes[3] << 24,
bytes[4] |
bytes[5] << 8 |
bytes[6] << 16 |
bytes[7] << 24,
unsigned
);
};
/**
* Creates a Long from its big endian byte representation.
* @param {!Array.<number>} bytes Big endian byte representation
* @param {boolean=} unsigned Whether unsigned or not, defaults to signed
* @returns {Long} The corresponding Long value
*/
Long.fromBytesBE = function fromBytesBE(bytes, unsigned) {
return new Long(
bytes[4] << 24 |
bytes[5] << 16 |
bytes[6] << 8 |
bytes[7],
bytes[0] << 24 |
bytes[1] << 16 |
bytes[2] << 8 |
bytes[3],
unsigned
);
};
var S2 =
(function (exports) {
'use strict';
// var S2 = exports.S2 = { L: {} };
var S2 = { L: {} };
S2.L.LatLng = function (/*Number*/ rawLat, /*Number*/ rawLng, /*Boolean*/ noWrap) {
var lat = parseFloat(rawLat, 10);
var lng = parseFloat(rawLng, 10);
if (isNaN(lat) || isNaN(lng)) {
throw new Error('Invalid LatLng object: (' + rawLat + ', ' + rawLng + ')');
}
if (noWrap !== true) {
lat = Math.max(Math.min(lat, 90), -90); // clamp latitude into -90..90
lng = (lng + 180) % 360 + ((lng < -180 || lng === 180) ? 180 : -180); // wrap longtitude into -180..180
}
return { lat: lat, lng: lng };
};
S2.L.LatLng.DEG_TO_RAD = Math.PI / 180;
S2.L.LatLng.RAD_TO_DEG = 180 / Math.PI;
/*
S2.LatLngToXYZ = function(latLng) {
// http://stackoverflow.com/questions/8981943/lat-long-to-x-y-z-position-in-js-not-working
var lat = latLng.lat;
var lon = latLng.lng;
var DEG_TO_RAD = Math.PI / 180.0;
var phi = lat * DEG_TO_RAD;
var theta = lon * DEG_TO_RAD;
var cosLat = Math.cos(phi);
var sinLat = Math.sin(phi);
var cosLon = Math.cos(theta);
var sinLon = Math.sin(theta);
var rad = 500.0;
return [
rad * cosLat * cosLon
, rad * cosLat * sinLon
, rad * sinLat
];
};
*/
S2.LatLngToXYZ = function (latLng) {
var d2r = S2.L.LatLng.DEG_TO_RAD;
var phi = latLng.lat * d2r;
var theta = latLng.lng * d2r;
var cosphi = Math.cos(phi);
return [Math.cos(theta) * cosphi, Math.sin(theta) * cosphi, Math.sin(phi)];
};
S2.XYZToLatLng = function (xyz) {
var r2d = S2.L.LatLng.RAD_TO_DEG;
var lat = Math.atan2(xyz[2], Math.sqrt(xyz[0] * xyz[0] + xyz[1] * xyz[1]));
var lng = Math.atan2(xyz[1], xyz[0]);
return S2.L.LatLng(lat * r2d, lng * r2d);
};
var largestAbsComponent = function (xyz) {
var temp = [Math.abs(xyz[0]), Math.abs(xyz[1]), Math.abs(xyz[2])];
if (temp[0] > temp[1]) {
if (temp[0] > temp[2]) {
return 0;
} else {
return 2;
}
} else {
if (temp[1] > temp[2]) {
return 1;
} else {
return 2;
}
}
};
var faceXYZToUV = function (face, xyz) {
var u, v;
switch (face) {
case 0: u = xyz[1] / xyz[0]; v = xyz[2] / xyz[0]; break;
case 1: u = -xyz[0] / xyz[1]; v = xyz[2] / xyz[1]; break;
case 2: u = -xyz[0] / xyz[2]; v = -xyz[1] / xyz[2]; break;
case 3: u = xyz[2] / xyz[0]; v = xyz[1] / xyz[0]; break;
case 4: u = xyz[2] / xyz[1]; v = -xyz[0] / xyz[1]; break;
case 5: u = -xyz[1] / xyz[2]; v = -xyz[0] / xyz[2]; break;
default: throw { error: 'Invalid face' };
}
return [u, v];
};
S2.XYZToFaceUV = function (xyz) {
var face = largestAbsComponent(xyz);
if (xyz[face] < 0) {
face += 3;
}
var uv = faceXYZToUV(face, xyz);
return [face, uv];
};
S2.FaceUVToXYZ = function (face, uv) {
var u = uv[0];
var v = uv[1];
switch (face) {
case 0: return [1, u, v];
case 1: return [-u, 1, v];
case 2: return [-u, -v, 1];
case 3: return [-1, -v, -u];
case 4: return [v, -1, -u];
case 5: return [v, u, -1];
default: throw { error: 'Invalid face' };
}
};
var singleSTtoUV = function (st) {
if (st >= 0.5) {
return (1 / 3.0) * (4 * st * st - 1);
} else {
return (1 / 3.0) * (1 - (4 * (1 - st) * (1 - st)));
}
};
S2.STToUV = function (st) {
return [singleSTtoUV(st[0]), singleSTtoUV(st[1])];
};
var singleUVtoST = function (uv) {
if (uv >= 0) {
return 0.5 * Math.sqrt(1 + 3 * uv);
} else {
return 1 - 0.5 * Math.sqrt(1 - 3 * uv);
}
};
S2.UVToST = function (uv) {
return [singleUVtoST(uv[0]), singleUVtoST(uv[1])];
};
S2.STToIJ = function (st, order) {
var maxSize = (1 << order);
var singleSTtoIJ = function (st) {
var ij = Math.floor(st * maxSize);
return Math.max(0, Math.min(maxSize - 1, ij));
};
return [singleSTtoIJ(st[0]), singleSTtoIJ(st[1])];
};
S2.IJToST = function (ij, order, offsets) {
var maxSize = (1 << order);
return [
(ij[0] + offsets[0]) / maxSize,
(ij[1] + offsets[1]) / maxSize
];
};
var rotateAndFlipQuadrant = function (n, point, rx, ry) {
var newX, newY;
if (ry == 0) {
if (rx == 1) {
point.x = n - 1 - point.x;
point.y = n - 1 - point.y
}
var x = point.x;
point.x = point.y
point.y = x;
}
}
// hilbert space-filling curve
// based on http://blog.notdot.net/2009/11/Damn-Cool-Algorithms-Spatial-indexing-with-Quadtrees-and-Hilbert-Curves
// note: rather then calculating the final integer hilbert position, we just return the list of quads
// this ensures no precision issues whth large orders (S3 cell IDs use up to 30), and is more
// convenient for pulling out the individual bits as needed later
var pointToHilbertQuadList = function (x, y, order, face) {
var hilbertMap = {
'a': [[0, 'd'], [1, 'a'], [3, 'b'], [2, 'a']],
'b': [[2, 'b'], [1, 'b'], [3, 'a'], [0, 'c']],
'c': [[2, 'c'], [3, 'd'], [1, 'c'], [0, 'b']],
'd': [[0, 'a'], [3, 'c'], [1, 'd'], [2, 'd']]
};
if ('number' !== typeof face) {
console.warn(new Error("called pointToHilbertQuadList without face value, defaulting to '0'").stack);
}
var currentSquare = (face % 2) ? 'd' : 'a';
var positions = [];
for (var i = order - 1; i >= 0; i--) {
var mask = 1 << i;
var quad_x = x & mask ? 1 : 0;
var quad_y = y & mask ? 1 : 0;
var t = hilbertMap[currentSquare][quad_x * 2 + quad_y];
positions.push(t[0]);
currentSquare = t[1];
}
return positions;
};
// S2Cell class
S2.S2Cell = function () { };
S2.S2Cell.FromHilbertQuadKey = function (hilbertQuadkey) {
var parts = hilbertQuadkey.split('/');
var face = parseInt(parts[0]);
var position = parts[1];
var maxLevel = position.length;
var point = {
x: 0,
y: 0
};
var i;
var level;
var bit;
var rx, ry;
var val;
for (i = maxLevel - 1; i >= 0; i--) {
level = maxLevel - i;
bit = position[i];
rx = 0;
ry = 0;
if (bit === '1') {
ry = 1;
}
else if (bit === '2') {
rx = 1;
ry = 1;
}
else if (bit === '3') {
rx = 1;
}
val = Math.pow(2, level - 1);
rotateAndFlipQuadrant(val, point, rx, ry);
point.x += val * rx;
point.y += val * ry;
}
if (face % 2 === 1) {
var t = point.x;
point.x = point.y;
point.y = t;
}
return S2.S2Cell.FromFaceIJ(parseInt(face), [point.x, point.y], level);
};
//static method to construct
S2.S2Cell.FromLatLng = function (latLng, level) {
if ((!latLng.lat && latLng.lat !== 0) || (!latLng.lng && latLng.lng !== 0)) {
throw new Error("Pass { lat: lat, lng: lng } to S2.S2Cell.FromLatLng");
}
var xyz = S2.LatLngToXYZ(latLng);
var faceuv = S2.XYZToFaceUV(xyz);
var st = S2.UVToST(faceuv[1]);
var ij = S2.STToIJ(st, level);
return S2.S2Cell.FromFaceIJ(faceuv[0], ij, level);
};
/*
S2.faceIjLevelToXyz = function (face, ij, level) {
var st = S2.IJToST(ij, level, [0.5, 0.5]);
var uv = S2.STToUV(st);
var xyz = S2.FaceUVToXYZ(face, uv);
return S2.XYZToLatLng(xyz);
return xyz;
};
*/
S2.S2Cell.FromFaceIJ = function (face, ij, level) {
var cell = new S2.S2Cell();
cell.face = face;
cell.ij = ij;
cell.level = level;
return cell;
};
S2.S2Cell.prototype.toString = function () {
return 'F' + this.face + 'ij[' + this.ij[0] + ',' + this.ij[1] + ']@' + this.level;
};
S2.S2Cell.prototype.getLatLng = function () {
var st = S2.IJToST(this.ij, this.level, [0.5, 0.5]);
var uv = S2.STToUV(st);
var xyz = S2.FaceUVToXYZ(this.face, uv);
return S2.XYZToLatLng(xyz);
};
S2.S2Cell.prototype.getCornerLatLngs = function () {
var result = [];
var offsets = [
[0.0, 0.0],
[0.0, 1.0],
[1.0, 1.0],
[1.0, 0.0]
];
for (var i = 0; i < 4; i++) {
var st = S2.IJToST(this.ij, this.level, offsets[i]);
var uv = S2.STToUV(st);
var xyz = S2.FaceUVToXYZ(this.face, uv);
result.push(S2.XYZToLatLng(xyz));
}
return result;
};
S2.S2Cell.prototype.getFaceAndQuads = function () {
var quads = pointToHilbertQuadList(this.ij[0], this.ij[1], this.level, this.face);
return [this.face, quads];
};
S2.S2Cell.prototype.toHilbertQuadkey = function () {
var quads = pointToHilbertQuadList(this.ij[0], this.ij[1], this.level, this.face);
return this.face.toString(10) + '/' + quads.join('');
};
S2.latLngToNeighborKeys = S2.S2Cell.latLngToNeighborKeys = function (lat, lng, level) {
return S2.S2Cell.FromLatLng({ lat: lat, lng: lng }, level).getNeighbors().map(function (cell) {
return cell.toHilbertQuadkey();
});
};
S2.S2Cell.prototype.getNeighbors = function () {
var fromFaceIJWrap = function (face, ij, level) {
var maxSize = (1 << level);
if (ij[0] >= 0 && ij[1] >= 0 && ij[0] < maxSize && ij[1] < maxSize) {
// no wrapping out of bounds
return S2.S2Cell.FromFaceIJ(face, ij, level);
} else {
// the new i,j are out of range.
// with the assumption that they're only a little past the borders we can just take the points as
// just beyond the cube face, project to XYZ, then re-create FaceUV from the XYZ vector
var st = S2.IJToST(ij, level, [0.5, 0.5]);
var uv = S2.STToUV(st);
var xyz = S2.FaceUVToXYZ(face, uv);
var faceuv = S2.XYZToFaceUV(xyz);
face = faceuv[0];
uv = faceuv[1];
st = S2.UVToST(uv);
ij = S2.STToIJ(st, level);
return S2.S2Cell.FromFaceIJ(face, ij, level);
}
};
var face = this.face;
var i = this.ij[0];
var j = this.ij[1];
var level = this.level;
return [
fromFaceIJWrap(face, [i - 1, j], level),
fromFaceIJWrap(face, [i, j - 1], level),
fromFaceIJWrap(face, [i + 1, j], level),
fromFaceIJWrap(face, [i, j + 1], level)
];
};
//
// Functional Style
//
S2.FACE_BITS = 3;
S2.MAX_LEVEL = 30;
S2.POS_BITS = (2 * S2.MAX_LEVEL) + 1; // 61 (60 bits of data, 1 bit lsb marker)
S2.facePosLevelToId = S2.S2Cell.facePosLevelToId = S2.fromFacePosLevel = function (faceN, posS, levelN) {
var faceB;
var posB;
var bin;
if (!levelN) {
levelN = posS.length;
}
if (posS.length > levelN) {
posS = posS.substr(0, levelN);
}
// 3-bit face value
faceB = Long.fromString(faceN.toString(10), true, 10).toString(2);
while (faceB.length < S2.FACE_BITS) {
faceB = '0' + faceB;
}
// 60-bit position value
posB = Long.fromString(posS, true, 4).toString(2);
while (posB.length < (2 * levelN)) {
posB = '0' + posB;
}
bin = faceB + posB;
// 1-bit lsb marker
bin += '1';
// n-bit padding to 64-bits
while (bin.length < (S2.FACE_BITS + S2.POS_BITS)) {
bin += '0';
}
return Long.fromString(bin, true, 2).toString(10);
};
S2.keyToId = S2.S2Cell.keyToId
= S2.toId = S2.toCellId = S2.fromKey
= function (key) {
var parts = key.split('/');
return S2.fromFacePosLevel(parts[0], parts[1], parts[1].length);
};
S2.idToKey = S2.S2Cell.idToKey
= S2.S2Cell.toKey = S2.toKey
= S2.fromId = S2.fromCellId
= S2.S2Cell.toHilbertQuadkey = S2.toHilbertQuadkey
= function (idS) {
var bin = Long.fromString(idS, true, 10).toString(2);
while (bin.length < (S2.FACE_BITS + S2.POS_BITS)) {
bin = '0' + bin;
}
// MUST come AFTER binstr has been left-padded with '0's
var lsbIndex = bin.lastIndexOf('1');
// substr(start, len)
// substring(start, end) // includes start, does not include end
var faceB = bin.substring(0, 3);
// posB will always be a multiple of 2 (or it's invalid)
var posB = bin.substring(3, lsbIndex);
var levelN = posB.length / 2;
var faceS = Long.fromString(faceB, true, 2).toString(10);
var posS = Long.fromString(posB, true, 2).toString(4);
while (posS.length < levelN) {
posS = '0' + posS;
}
return faceS + '/' + posS;
};
S2.keyToLatLng = S2.S2Cell.keyToLatLng = function (key) {
var cell2 = S2.S2Cell.FromHilbertQuadKey(key);
return cell2.getLatLng();
};
S2.idToLatLng = S2.S2Cell.idToLatLng = function (id) {
var key = S2.idToKey(id);
return S2.keyToLatLng(key);
};
S2.S2Cell.latLngToKey = S2.latLngToKey
= S2.latLngToQuadkey = function (lat, lng, level) {
if (isNaN(level) || level < 1 || level > 30) {
throw new Error("'level' is not a number between 1 and 30 (but it should be)");
}
// TODO
//
// S2.idToLatLng(id)
// S2.keyToLatLng(key)
// S2.nextFace(key) // prevent wrapping on nextKey
// S2.prevFace(key) // prevent wrapping on prevKey
//
// .toKeyArray(id) // face,quadtree
// .toKey(id) // hilbert
// .toPoint(id) // ij
// .toId(key) // uint64 (as string)
// .toLong(key) // long.js
// .toLatLng(id) // object? or array?, or string (with comma)?
//
// maybe S2.HQ.x, S2.GPS.x, S2.CI.x?
return S2.S2Cell.FromLatLng({ lat: lat, lng: lng }, level).toHilbertQuadkey();
};
S2.S2Cell.latLngToId = S2.latLngToId = function (lat, lng, level) {
return S2.keyToId(S2.S2Cell.latLngToKey(lat, lng, level));
};
S2.stepKey = function (key, num) {
var parts = key.split('/');
var faceS = parts[0];
var posS = parts[1];
var level = parts[1].length;
var posL = Long.fromString(posS, true, 4);
// TODO handle wrapping (0 === pos + 1)
// (only on the 12 edges of the globe)
var otherL;
if (num > 0) {
otherL = posL.add(Math.abs(num));
}
else if (num < 0) {
otherL = posL.subtract(Math.abs(num));
}
var otherS = otherL.toString(4);
if ('0' === otherS) {
console.warning(new Error("face/position wrapping is not yet supported"));
}
while (otherS.length < level) {
otherS = '0' + otherS;
}
return faceS + '/' + otherS;
};
S2.S2Cell.prevKey = S2.prevKey = function (key) {
return S2.stepKey(key, -1);
};
S2.S2Cell.nextKey = S2.nextKey = function (key) {
return S2.stepKey(key, 1);
};
return S2
})({});
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