CesiumMath

CesiumMath

Math functions.
Source: Core/Math.js, line 18

Members

staticconstantCesiumMath.DEGREES_PER_RADIAN :Number

The number of degrees in a radian.
Default Value: 180.0 / Math.PI
Source: Core/Math.js, line 365

staticconstantCesiumMath.EPSILON1 :Number

0.1
Source: Core/Math.js, line 25

staticconstantCesiumMath.EPSILON2 :Number

0.01
Source: Core/Math.js, line 32

staticconstantCesiumMath.EPSILON3 :Number

0.001
Source: Core/Math.js, line 39

staticconstantCesiumMath.EPSILON4 :Number

0.0001
Source: Core/Math.js, line 46

staticconstantCesiumMath.EPSILON5 :Number

0.00001
Source: Core/Math.js, line 53

staticconstantCesiumMath.EPSILON6 :Number

0.000001
Source: Core/Math.js, line 60

staticconstantCesiumMath.EPSILON7 :Number

0.0000001
Source: Core/Math.js, line 67

staticconstantCesiumMath.EPSILON8 :Number

0.00000001
Source: Core/Math.js, line 74

staticconstantCesiumMath.EPSILON9 :Number

0.000000001
Source: Core/Math.js, line 81

staticconstantCesiumMath.EPSILON10 :Number

0.0000000001
Source: Core/Math.js, line 88

staticconstantCesiumMath.EPSILON11 :Number

0.00000000001
Source: Core/Math.js, line 95

staticconstantCesiumMath.EPSILON12 :Number

0.000000000001
Source: Core/Math.js, line 102

staticconstantCesiumMath.EPSILON13 :Number

0.0000000000001
Source: Core/Math.js, line 109

staticconstantCesiumMath.EPSILON14 :Number

0.00000000000001
Source: Core/Math.js, line 116

staticconstantCesiumMath.EPSILON15 :Number

0.000000000000001
Source: Core/Math.js, line 123

staticconstantCesiumMath.EPSILON16 :Number

0.0000000000000001
Source: Core/Math.js, line 130

staticconstantCesiumMath.EPSILON17 :Number

0.00000000000000001
Source: Core/Math.js, line 137

staticconstantCesiumMath.EPSILON18 :Number

0.000000000000000001
Source: Core/Math.js, line 144

staticconstantCesiumMath.EPSILON19 :Number

0.0000000000000000001
Source: Core/Math.js, line 151

staticconstantCesiumMath.EPSILON20 :Number

0.00000000000000000001
Source: Core/Math.js, line 158

staticconstantCesiumMath.GRAVITATIONALPARAMETER :Number

3.986004418e14
Source: Core/Math.js, line 165

staticconstantCesiumMath.LUNAR_RADIUS :Number

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.
Source: Core/Math.js, line 181

staticconstantCesiumMath.ONE_OVER_PI :Number

1/pi
Source: Core/Math.js, line 291

staticconstantCesiumMath.ONE_OVER_TWO_PI :Number

1/2pi
Source: Core/Math.js, line 347

staticconstantCesiumMath.PI :Number

pi
Source: Core/Math.js, line 283

staticconstantCesiumMath.PI_OVER_FOUR :Number

pi/4
Source: Core/Math.js, line 315

staticconstantCesiumMath.PI_OVER_SIX :Number

pi/6
Source: Core/Math.js, line 323

staticconstantCesiumMath.PI_OVER_THREE :Number

pi/3
Source: Core/Math.js, line 307

staticconstantCesiumMath.PI_OVER_TWO :Number

pi/2
Source: Core/Math.js, line 299

staticconstantCesiumMath.RADIANS_PER_ARCSECOND :Number

The number of radians in an arc second.
Default Value: CesiumMath.RADIANS_PER_DEGREE / 3600.0
Source: Core/Math.js, line 374

staticconstantCesiumMath.RADIANS_PER_DEGREE :Number

The number of radians in a degree.
Default Value: Math.PI / 180.0
Source: Core/Math.js, line 356

staticconstantCesiumMath.SIXTY_FOUR_KILOBYTES :Number

64 * 1024
Source: Core/Math.js, line 188

staticconstantCesiumMath.SOLAR_RADIUS :Number

Radius of the sun in meters: 6.955e8
Source: Core/Math.js, line 172

staticconstantCesiumMath.THREE_PI_OVER_TWO :Number

3pi/2
Source: Core/Math.js, line 331

staticconstantCesiumMath.TWO_PI :Number

2pi
Source: Core/Math.js, line 339

Methods

staticCesiumMath.acosClamped(value) → number

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 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.
Source: Core/Math.js, line 687

staticCesiumMath.asinClamped(value) → number

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 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.
Source: Core/Math.js, line 699

staticCesiumMath.clamp(value, min, max)

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.
Source: Core/Math.js, line 633

staticCesiumMath.convertLongitudeRange(angle) → Number

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));
Source: Core/Math.js, line 414

staticCesiumMath.cosh(value)

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.
Source: Core/Math.js, line 255

staticCesiumMath.equalsEpsilon(left, right, epsilon) → Boolean

Determines if two values are equal within the provided epsilon. This is useful to avoid problems due to roundoff error when comparing floating-point values directly.
Name Type Default Description
left Number The first value to compare.
right Number The other value to compare.
epsilon Number 0.0 optional The maximum inclusive delta between left and right where they will be considered equal.
Returns:
true if the values are equal within the epsilon; otherwise, false.
Example:
var b = Cesium.Math.equalsEpsilon(0.0, 0.01, Cesium.Math.EPSILON2); // true
var b = Cesium.Math.equalsEpsilon(0.0, 0.1, Cesium.Math.EPSILON2);  // false
Source: Core/Math.js, line 492

staticCesiumMath.factorial(n) → Number

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:
Source: Core/Math.js, line 522

staticCesiumMath.incrementWrap(n, maximumValue, minimumValue) → Number

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
Source: Core/Math.js, line 553

staticCesiumMath.isPowerOfTwo(n) → Boolean

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
Source: Core/Math.js, line 584

staticCesiumMath.lerp(p, q, time) → Number

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
Source: Core/Math.js, line 273

staticCesiumMath.negativePiToPi(angle) → Number

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].
Source: Core/Math.js, line 440

staticCesiumMath.nextPowerOfTwo(n) → Number

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
Source: Core/Math.js, line 606

staticCesiumMath.nextRandomNumber()

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:
Source: Core/Math.js, line 675

staticCesiumMath.setRandomNumberSeed(seed)

Sets the seed used by the random number generator in CesiumMath#nextRandomNumber.
Name Type Description
seed Number An integer used as the seed.
Source: Core/Math.js, line 656

staticCesiumMath.sign(value) → Number

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.
Source: Core/Math.js, line 197

staticCesiumMath.sinh(value)

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.
Source: Core/Math.js, line 229

staticCesiumMath.toDegrees(radians) → Number

Converts radians to degrees.
Name Type Description
radians Number The angle to convert in radians.
Returns:
The corresponding angle in degrees.
Source: Core/Math.js, line 395

staticCesiumMath.toRadians(degrees) → Number

Converts degrees to radians.
Name Type Description
degrees Number The angle to convert in degrees.
Returns:
The corresponding angle in radians.
Source: Core/Math.js, line 381

staticCesiumMath.zeroToTwoPi(angle) → Number

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].
Source: Core/Math.js, line 467