Namespace: Utilities

LittleJS Utility Classes and Functions

General purpose math library
Vector2 - fast, simple, easy 2D vector class
Color - holds a rgba color with some math functions
Timer - tracks time automatically
RandomGenerator - seeded random number generator

Source: engineUtilities.js, line 1

Members

(static, constant) BLACK :Color

Color - Black

Type:

Color

Source: engineUtilities.js, line 828

(static, constant) BLUE :Color

Color - Blue

Type:

Color

Source: engineUtilities.js, line 863

(static, constant) CYAN :Color

Color - Cyan

Type:

Color

Source: engineUtilities.js, line 858

(static, constant) GRAY :Color

Color - Gray

Type:

Color

Source: engineUtilities.js, line 833

(static, constant) GREEN :Color

Color - Green

Type:

Color

Source: engineUtilities.js, line 853

(static, constant) MAGENTA :Color

Color - Magenta

Type:

Color

Source: engineUtilities.js, line 873

(static, constant) ORANGE :Color

Color - Orange

Type:

Color

Source: engineUtilities.js, line 843

(static, constant) PI :Number

A shortcut to get Math.PI

Type:

Number

Default Value: Math.PI
Source: engineUtilities.js, line 17

(static, constant) PURPLE :Color

Color - Purple

Type:

Color

Source: engineUtilities.js, line 868

(static, constant) RED :Color

Color - Red

Type:

Color

Source: engineUtilities.js, line 838

(static, constant) WHITE :Color

Color - White

Type:

Color

Source: engineUtilities.js, line 823

(static, constant) YELLOW :Color

Color - Yellow

Type:

Color

Source: engineUtilities.js, line 848

Methods

(static) abs(value) → {Number}

Returns absolute value of value passed in

Parameters:

Name	Type	Description
`value`	Number

Source: engineUtilities.js, line 23

Returns:

Type:: Number

(static) clamp(value, minopt, maxopt) → {Number}

Clamps the value between max and min

Parameters:

Name	Type	Attributes	Default
`value`	Number
`min`	Number	<optional>	0
`max`	Number	<optional>	1

Source: engineUtilities.js, line 58

Returns:

Type:: Number

(static) distanceAngle(angleA, angleB) → {Number}

Returns signed wrapped distance between the two angles passed in

Parameters:

Name	Type	Description
`angleA`	Number
`angleB`	Number

Source: engineUtilities.js, line 101

Returns:

Type:: Number

(static) distanceWrap(valueA, valueB, wrapSizeopt) → {Number}

Returns signed wrapped distance between the two values passed in

Parameters:

Name	Type	Attributes	Default
`valueA`	Number
`valueB`	Number
`wrapSize`	Number	<optional>	1

Source: engineUtilities.js, line 83

Returns:

Type:: Number

(static) formatTime(t) → {String}

Formats seconds to mm:ss style for display purposes

Parameters:

Name	Type	Description
`t`	Number	time in seconds

Source: engineUtilities.js, line 190

Returns:

Type:: String

(static) hsl(hopt, sopt, lopt, aopt) → {Color}

Create a color object with HSLA values, white by default

Parameters:

Name	Type	Attributes	Default	Description
`h`	Number	<optional>	0	hue
`s`	Number	<optional>	0	saturation
`l`	Number	<optional>	1	lightness
`a`	Number	<optional>	1	alpha

Source: engineUtilities.js, line 575

Returns:

Type:: Color

(static) isColor(c) → {Boolean}

Check if object is a valid Color

Parameters:

Name	Type	Description
`c`	any

Source: engineUtilities.js, line 583

Returns:

Type:: Boolean

(static) isIntersecting(start, end, pos, size) → {Boolean}

Returns true if a line segment is intersecting an axis aligned box

Parameters:

Name	Type	Description
`start`	Vector2	Start of raycast
`end`	Vector2	End of raycast
`pos`	Vector2	Center of box
`size`	Vector2	Size of box

Source: engineUtilities.js, line 143

Returns:

True if intersecting

Type:: Boolean

(static) isOverlapping(posA, sizeA, posB, sizeBopt) → {Boolean}

Returns true if two axis aligned bounding boxes are overlapping

Parameters:

Name	Type	Attributes	Default	Description
`posA`	Vector2			Center of box A
`sizeA`	Vector2			Size of box A
`posB`	Vector2			Center of box B
`sizeB`	Vector2	<optional>	(0,0)	Size of box B, a point if undefined

Source: engineUtilities.js, line 130

Returns:

True if overlapping

Type:: Boolean

(static) isVector2(v) → {Boolean}

Check if object is a valid Vector2

Parameters:

Name	Type	Description
`v`	any

Source: engineUtilities.js, line 316

Returns:

Type:: Boolean

(static) lerp(percent, valueA, valueB) → {Number}

Linearly interpolates between values passed in using percent

Parameters:

Name	Type	Description
`percent`	Number
`valueA`	Number
`valueB`	Number

Source: engineUtilities.js, line 75

Returns:

Type:: Number

(static) lerpAngle(percent, angleA, angleB) → {Number}

Linearly interpolates between the angles passed in with wrapping

Parameters:

Name	Type	Description
`percent`	Number
`angleA`	Number
`angleB`	Number

Source: engineUtilities.js, line 109

Returns:

Type:: Number

(static) lerpWrap(percent, valueA, valueB, wrapSizeopt) → {Number}

Linearly interpolates between values passed in with wrapping

Parameters:

Name	Type	Attributes	Default
`percent`	Number
`valueA`	Number
`valueB`	Number
`wrapSize`	Number	<optional>	1

Source: engineUtilities.js, line 93

Returns:

Type:: Number

(static) max(valueA, valueB) → {Number}

Returns highest of two values passed in

Parameters:

Name	Type	Description
`valueA`	Number
`valueB`	Number

Source: engineUtilities.js, line 37

Returns:

Type:: Number

(static) min(valueA, valueB) → {Number}

Returns lowest of two values passed in

Parameters:

Name	Type	Description
`valueA`	Number
`valueB`	Number

Source: engineUtilities.js, line 30

Returns:

Type:: Number

(static) mod(dividend, divisoropt) → {Number}

Returns first parm modulo the second param, but adjusted so negative numbers work as expected

Parameters:

Name	Type	Attributes	Default	Description
`dividend`	Number
`divisor`	Number	<optional>	1

Source: engineUtilities.js, line 50

Returns:

Type:: Number

(static) nearestPowerOfTwo(value) → {Number}

Returns the nearest power of two not less then the value

Parameters:

Name	Type	Description
`value`	Number

Source: engineUtilities.js, line 121

Returns:

Type:: Number

(static) percent(value, valueA, valueB) → {Number}

Returns what percentage the value is between valueA and valueB

Parameters:

Name	Type	Description
`value`	Number
`valueA`	Number
`valueB`	Number

Source: engineUtilities.js, line 66

Returns:

Type:: Number

(static) rgb(ropt, gopt, bopt, aopt) → {Color}

Create a color object with RGBA values, white by default

Parameters:

Name	Type	Attributes	Default	Description
`r`	Number	<optional>	1	red
`g`	Number	<optional>	1	green
`b`	Number	<optional>	1	blue
`a`	Number	<optional>	1	alpha

Source: engineUtilities.js, line 564

Returns:

Type:: Color

(static) sign(value) → {Number}

Returns the sign of value passed in

Parameters:

Name	Type	Description
`value`	Number

Source: engineUtilities.js, line 43

Returns:

Type:: Number

(static) smoothStep(percent) → {Number}

Applies smoothstep function to the percentage value

Parameters:

Name	Type	Description
`percent`	Number

Source: engineUtilities.js, line 115

Returns:

Type:: Number

(static) vec2(xopt, yopt) → {Vector2}

Create a 2d vector, can take another Vector2 to copy, 2 scalars, or 1 scalar

Parameters:

Name	Type	Attributes	Default	Description
`x`	Number \| Vector2	<optional>	0
`y`	Number	<optional>

Source: engineUtilities.js, line 303

Returns:

Type:: Vector2

Example

let a = vec2(0, 1); // vector with coordinates (0, 1)
let b = vec2(a);    // copy a into b
a = vec2(5);        // set a to (5, 5)
b = vec2();         // set b to (0, 0)

(static) wave(frequencyopt, amplitudeopt, topt) → {Number}

Returns an oscillating wave between 0 and amplitude with frequency of 1 Hz by default

Parameters:

Name	Type	Attributes	Default	Description
`frequency`	Number	<optional>	1	Frequency of the wave in Hz
`amplitude`	Number	<optional>	1	Amplitude (max height) of the wave
`t`	Number	<optional>	time	Value to use for time of the wave

Source: engineUtilities.js, line 183

Returns:

Value waving between 0 and amplitude

Type:: Number