CesiumMath

CesiumMath()
Core/Math.js 19

Math functions.

Members

staticconstantCesium.CesiumMath.DEGREES_PER_RADIAN : Number
Core/Math.js 399

The number of degrees in a radian.
Default Value: 180.0 / Math.PI

staticconstantCesium.CesiumMath.EPSILON1 : Number
Core/Math.js 26

0.1

staticconstantCesium.CesiumMath.EPSILON2 : Number
Core/Math.js 33

0.01

staticconstantCesium.CesiumMath.EPSILON3 : Number
Core/Math.js 40

0.001

staticconstantCesium.CesiumMath.EPSILON4 : Number
Core/Math.js 47

0.0001

staticconstantCesium.CesiumMath.EPSILON5 : Number
Core/Math.js 54

0.00001

staticconstantCesium.CesiumMath.EPSILON6 : Number
Core/Math.js 61

0.000001

staticconstantCesium.CesiumMath.EPSILON7 : Number
Core/Math.js 68

0.0000001

staticconstantCesium.CesiumMath.EPSILON8 : Number
Core/Math.js 75

0.00000001

staticconstantCesium.CesiumMath.EPSILON9 : Number
Core/Math.js 82

0.000000001

staticconstantCesium.CesiumMath.EPSILON10 : Number
Core/Math.js 89

0.0000000001

staticconstantCesium.CesiumMath.EPSILON11 : Number
Core/Math.js 96

0.00000000001

staticconstantCesium.CesiumMath.EPSILON12 : Number
Core/Math.js 103

0.000000000001

staticconstantCesium.CesiumMath.EPSILON13 : Number
Core/Math.js 110

0.0000000000001

staticconstantCesium.CesiumMath.EPSILON14 : Number
Core/Math.js 117

0.00000000000001

staticconstantCesium.CesiumMath.EPSILON15 : Number
Core/Math.js 124

0.000000000000001

staticconstantCesium.CesiumMath.EPSILON16 : Number
Core/Math.js 131

0.0000000000000001

staticconstantCesium.CesiumMath.EPSILON17 : Number
Core/Math.js 138

0.00000000000000001

staticconstantCesium.CesiumMath.EPSILON18 : Number
Core/Math.js 145

0.000000000000000001

staticconstantCesium.CesiumMath.EPSILON19 : Number
Core/Math.js 152

0.0000000000000000001

staticconstantCesium.CesiumMath.EPSILON20 : Number
Core/Math.js 159

0.00000000000000000001

staticconstantCesium.CesiumMath.GRAVITATIONALPARAMETER : Number
Core/Math.js 166

3.986004418e14

staticconstantCesium.CesiumMath.LUNAR_RADIUS : Number
Core/Math.js 182

The mean radius of the moon, according to the "Report of the IAU/IAG Working Group on Cartographic Coordinates and Rotational Elements of the Planets and satellites: 2000", Celestial Mechanics 82: 83-110, 2002.

staticconstantCesium.CesiumMath.ONE_OVER_PI : Number
Core/Math.js 325

1/pi

staticconstantCesium.CesiumMath.ONE_OVER_TWO_PI : Number
Core/Math.js 381

1/2pi

staticconstantCesium.CesiumMath.PI : Number
Core/Math.js 317

pi

staticconstantCesium.CesiumMath.PI_OVER_FOUR : Number
Core/Math.js 349

pi/4

staticconstantCesium.CesiumMath.PI_OVER_SIX : Number
Core/Math.js 357

pi/6

staticconstantCesium.CesiumMath.PI_OVER_THREE : Number
Core/Math.js 341

pi/3

staticconstantCesium.CesiumMath.PI_OVER_TWO : Number
Core/Math.js 333

pi/2

staticconstantCesium.CesiumMath.RADIANS_PER_ARCSECOND : Number
Core/Math.js 408

The number of radians in an arc second.
Default Value: CesiumMath.RADIANS_PER_DEGREE / 3600.0

staticconstantCesium.CesiumMath.RADIANS_PER_DEGREE : Number
Core/Math.js 390

The number of radians in a degree.
Default Value: Math.PI / 180.0

staticconstantCesium.CesiumMath.SIXTY_FOUR_KILOBYTES : Number
Core/Math.js 189

64 * 1024

staticconstantCesium.CesiumMath.SOLAR_RADIUS : Number
Core/Math.js 173

Radius of the sun in meters: 6.955e8

staticconstantCesium.CesiumMath.THREE_PI_OVER_TWO : Number
Core/Math.js 365

3pi/2

staticconstantCesium.CesiumMath.TWO_PI : Number
Core/Math.js 373

2pi

Methods

staticCesium.CesiumMath.acosClamped(value) → Number
Core/Math.js 738

Computes Math.acos(value), but first clamps value to the range [-1.0, 1.0] so that the function will never return NaN.
Name Type Description
value Number The value for which to compute acos.
Returns:
The acos of the value if the value is in the range [-1.0, 1.0], or the acos of -1.0 or 1.0, whichever is closer, if the value is outside the range.

staticCesium.CesiumMath.asinClamped(value) → Number
Core/Math.js 755

Computes Math.asin(value), but first clamps value to the range [-1.0, 1.0] so that the function will never return NaN.
Name Type Description
value Number The value for which to compute asin.
Returns:
The asin of the value if the value is in the range [-1.0, 1.0], or the asin of -1.0 or 1.0, whichever is closer, if the value is outside the range.

staticCesium.CesiumMath.chordLength(angle, radius) → Number
Core/Math.js 771

Finds the chord length between two points given the circle's radius and the angle between the points.
Name Type Description
angle Number The angle between the two points.
radius Number The radius of the circle.
Returns:
The chord length.

staticCesium.CesiumMath.clamp(value, min, max) → Number
Core/Math.js 684

Constraint a value to lie between two values.
Name Type Description
value Number The value to constrain.
min Number The minimum value.
max Number The maximum value.
Returns:
The value clamped so that min <= value <= max.

staticCesium.CesiumMath.convertLongitudeRange(angle) → Number
Core/Math.js 448

Converts a longitude value, in radians, to the range [-Math.PI, Math.PI).
Name Type Description
angle Number The longitude value, in radians, to convert to the range [-Math.PI, Math.PI).
Returns:
The equivalent longitude value in the range [-Math.PI, Math.PI).
Example:
// Convert 270 degrees to -90 degrees longitude
var longitude = Cesium.Math.convertLongitudeRange(Cesium.Math.toRadians(270.0));

staticCesium.CesiumMath.cosh(value) → Number
Core/Math.js 289

Returns the hyperbolic cosine of a number. The hyperbolic cosine of value is defined to be (ex + e-x)/2.0 where e is Euler's number, approximately 2.71828183.

Special cases:

  • If the argument is NaN, then the result is NaN.
  • If the argument is infinite, then the result is positive infinity.
  • If the argument is zero, then the result is 1.0.

Name Type Description
value Number The number whose hyperbolic cosine is to be returned.
Returns:
The hyperbolic cosine of value.

staticCesium.CesiumMath.equalsEpsilon(left, right, relativeEpsilon, absoluteEpsilon) → Boolean
Core/Math.js 539

Determines if two values are equal using an absolute or relative tolerance test. This is useful to avoid problems due to roundoff error when comparing floating-point values directly. The values are first compared using an absolute tolerance test. If that fails, a relative tolerance test is performed. Use this test if you are unsure of the magnitudes of left and right.
Name Type Default Description
left Number The first value to compare.
right Number The other value to compare.
relativeEpsilon Number The maximum inclusive delta between left and right for the relative tolerance test.
absoluteEpsilon Number relativeEpsilon optional The maximum inclusive delta between left and right for the absolute tolerance test.
Returns:
true if the values are equal within the epsilon; otherwise, false.
Example:
var a = Cesium.Math.equalsEpsilon(0.0, 0.01, Cesium.Math.EPSILON2); // true
var b = Cesium.Math.equalsEpsilon(0.0, 0.1, Cesium.Math.EPSILON2);  // false
var c = Cesium.Math.equalsEpsilon(3699175.1634344, 3699175.2, Cesium.Math.EPSILON7); // true
var d = Cesium.Math.equalsEpsilon(3699175.1634344, 3699175.2, Cesium.Math.EPSILON9); // false

staticCesium.CesiumMath.factorial(n) → Number
Core/Math.js 573

Computes the factorial of the provided number.
Name Type Description
n Number The number whose factorial is to be computed.
Returns:
The factorial of the provided number or undefined if the number is less than 0.
Throws:
Example:
//Compute 7!, which is equal to 5040
var computedFactorial = Cesium.Math.factorial(7);
See:

staticCesium.CesiumMath.fromSNorm(value) → Number
Core/Math.js 238

Converts a SNORM value in the range [0, 255] to a scalar in the range [-1.0, 1.0].
Name Type Description
value Number SNORM value in the range [0, 255]
Returns:
Scalar in the range [-1.0, 1.0].
See:

staticCesium.CesiumMath.incrementWrap(n, maximumValue, minimumValue) → Number
Core/Math.js 604

Increments a number with a wrapping to a minimum value if the number exceeds the maximum value.
Name Type Default Description
n Number optional The number to be incremented.
maximumValue Number optional The maximum incremented value before rolling over to the minimum value.
minimumValue Number 0.0 optional The number reset to after the maximum value has been exceeded.
Returns:
The incremented number.
Throws:
Example:
var n = Cesium.Math.incrementWrap(5, 10, 0); // returns 6
var n = Cesium.Math.incrementWrap(10, 10, 0); // returns 0

staticCesium.CesiumMath.isPowerOfTwo(n) → Boolean
Core/Math.js 635

Determines if a positive integer is a power of two.
Name Type Description
n Number The positive integer to test.
Returns:
true if the number if a power of two; otherwise, false.
Throws:
Example:
var t = Cesium.Math.isPowerOfTwo(16); // true
var f = Cesium.Math.isPowerOfTwo(20); // false

staticCesium.CesiumMath.lerp(p, q, time) → Number
Core/Math.js 307

Computes the linear interpolation of two values.
Name Type Description
p Number The start value to interpolate.
q Number The end value to interpolate.
time Number The time of interpolation generally in the range [0.0, 1.0].
Returns:
The linearly interpolated value.
Example:
var n = Cesium.Math.lerp(0.0, 2.0, 0.5); // returns 1.0

staticCesium.CesiumMath.mod(m, n) → Number
Core/Math.js 509

The modulo operation that also works for negative dividends.
Name Type Description
m Number The dividend.
n Number The divisor.
Returns:
The remainder.

staticCesium.CesiumMath.negativePiToPi(angle) → Number
Core/Math.js 474

Produces an angle in the range -Pi <= angle <= Pi which is equivalent to the provided angle.
Name Type Description
angle Number in radians
Returns:
The angle in the range [-CesiumMath.PI, CesiumMath.PI].

staticCesium.CesiumMath.nextPowerOfTwo(n) → Number
Core/Math.js 657

Computes the next power-of-two integer greater than or equal to the provided positive integer.
Name Type Description
n Number The positive integer to test.
Returns:
The next power-of-two integer.
Throws:
Example:
var n = Cesium.Math.nextPowerOfTwo(29); // 32
var m = Cesium.Math.nextPowerOfTwo(32); // 32

staticCesium.CesiumMath.nextRandomNumber() → Number
Core/Math.js 726

Generates a random number in the range of [0.0, 1.0) using a Mersenne twister.
Returns:
A random number in the range of [0.0, 1.0).
See:

staticCesium.CesiumMath.setRandomNumberSeed(seed)
Core/Math.js 707

Sets the seed used by the random number generator in CesiumMath#nextRandomNumber.
Name Type Description
seed Number An integer used as the seed.

staticCesium.CesiumMath.sign(value) → Number
Core/Math.js 198

Returns the sign of the value; 1 if the value is positive, -1 if the value is negative, or 0 if the value is 0.
Name Type Description
value Number The value to return the sign of.
Returns:
The sign of value.

staticCesium.CesiumMath.signNotZero(value) → Number
Core/Math.js 216

Returns 1.0 if the given value is positive or zero, and -1.0 if it is negative. This is similar to CesiumMath#sign except that returns 1.0 instead of 0.0 when the input value is 0.0.
Name Type Description
value Number The value to return the sign of.
Returns:
The sign of value.

staticCesium.CesiumMath.sinh(value) → Number
Core/Math.js 263

Returns the hyperbolic sine of a number. The hyperbolic sine of value is defined to be (ex - e-x)/2.0 where e is Euler's number, approximately 2.71828183.

Special cases:

  • If the argument is NaN, then the result is NaN.
  • If the argument is infinite, then the result is an infinity with the same sign as the argument.
  • If the argument is zero, then the result is a zero with the same sign as the argument.

Name Type Description
value Number The number whose hyperbolic sine is to be returned.
Returns:
The hyperbolic sine of value.

staticCesium.CesiumMath.toDegrees(radians) → Number
Core/Math.js 429

Converts radians to degrees.
Name Type Description
radians Number The angle to convert in radians.
Returns:
The corresponding angle in degrees.

staticCesium.CesiumMath.toRadians(degrees) → Number
Core/Math.js 415

Converts degrees to radians.
Name Type Description
degrees Number The angle to convert in degrees.
Returns:
The corresponding angle in radians.

staticCesium.CesiumMath.toSNorm(value) → Number
Core/Math.js 227

Converts a scalar value in the range [-1.0, 1.0] to a 8-bit 2's complement number.
Name Type Description
value Number The scalar value in the range [-1.0, 1.0]
Returns:
The 8-bit 2's complement number, where 0 maps to -1.0 and 255 maps to 1.0.
See:

staticCesium.CesiumMath.zeroToTwoPi(angle) → Number
Core/Math.js 489

Produces an angle in the range 0 <= angle <= 2Pi which is equivalent to the provided angle.
Name Type Description
angle Number in radians
Returns:
The angle in the range [0, CesiumMath.TWO_PI].