Rac - Documentation

# | source: src/Rac.js, line 22

Root class of RAC. All drawable, style, control, and drawer classes are contained in this class.

An instance must be created with new Rac() in order to build drawable, style, and other objects.

To perform drawing operations, a drawer must be setup with setupDrawer. Currently the only available implementation is P5Drawer.

Constructor

new Rac()

# | source: src/Rac.js, line 22

Creates a new instance of Rac. The new instance has no drawer setup.

Classes

Angle
Arc
ArcControl
Bezier
Color
Composite
Control
Controller
Exception
Fill
P5Drawer
Point
Ray
RayControl
Segment
Shape
Stroke
StyleContainer
Text

Members

(static, constant) build :String

# | source: src/Rac.js, line 331

Build of the class. Intended for debugging purpouses.

Contains a commit-count and short-hash of the repository when the build was done.

Example

Rac.build // returns E.g. '1057-94b059d'

(static, constant) dated :String

# | source: src/Rac.js, line 347

Date of the build of the class. Intended for debugging purpouses.

Contains a ISO-8601 standard date when the build was done.

Example

Rac.dated // returns E.g. '2022-10-13T23:06:12.500Z'

(static, constant) TAU :Number

# | source: src/Rac.js, line 362

Tau, equal to Math.PI * 2.

See Tau Manifesto.

(static, constant) utils :utils

# | source: src/Rac.js, line 315

Container of utility functions. See the utils namespace for the available members.

Also available through rac.utils.

(static, constant) version :String

# | source: src/Rac.js, line 319

Version of the class. Equivalent to the version used for the npm package.

Example

Rac.version // returns E.g. '1.2.1'

(constant) build :String

# | source: src/Rac.js, line 41

Build of the instance, equivalent to Rac.build.

Example

rac.build // returns E.g. '1057-94b059d'

controller

# | source: src/Rac.js, line 179

Controller of the instance. This objecs handles all of the controls and pointer events related to this instance of Rac.

(constant) dated :String

# | source: src/Rac.js, line 53

Date of the build of the instance, equivalent to Rac.dated.

Example

rac.dated // returns E.g. '2022-10-13T23:06:12.500Z'

(nullable) drawer :Object

# | source: src/Rac.js, line 155

Drawer of the instance. This object handles the drawing for all drawable object created using this.

Default Value:

null

equalityThreshold :Number

# | source: src/Rac.js, line 85

Value used to determine equality between two numeric values. Used for values that tend to be integers, like screen coordinates. Used by equals.

When checking for equality x is equal to non-inclusive (x-equalityThreshold, x+equalityThreshold):

x is not equal to x ± equalityThreshold
x is equal to x ± equalityThreshold/2

Due to floating point precision some opertation like intersections can return odd or oscilating values. This threshold is used to snap values too close to a limit, as to prevent oscilating efects in user interaction.

The default value is based on 1/1000 of a point.

Default Value:

0.001

textFormatDefaults :Object

# | source: src/Rac.js, line 143

Defaults for the optional properties of Text.Format.

When a Text is draw which format.font or format.size are set to null, the values set here are used instead.

Properties:

Name	Type	Attributes	Default	Description
`font`	`String`	<nullable>	`null`	Default font, used when drawing a `Text` which `format.font` is set to `null`; when set to `null` the font is not set upon drawing
`size`	`Number`		`15`	Default size, used when drawing a `Text` which `format.size` is set to `null`

unitaryEqualityThreshold :Number

# | source: src/Rac.js, line 106

Value used to determine equality between two unitary numeric values. Used for values that tend to exist in the [0, 1] range, like angle.turn. Used by unitaryEquals.

Equality logic is the same as equalityThreshold.

The default value is based on 1/1000 of the turn of an complete circle arc of radius 500:

1/(500*6.28)/1000 = 0.000_000_318471338

Default Value:

0.000_000_3

utils :utils

# | source: src/Rac.js, line 117

Container of utility functions. See the utils namespace for the available members.

Also available through Rac.utils.

(constant) version :String

# | source: src/Rac.js, line 29

Version of the instance, equivalent to Rac.version.

Example

rac.version // returns E.g. '1.2.1'

Methods

(static) setupDrawableProtoFunctions(drawableClass)

# | source: src/attachProtoFunctions.js, line 32

Adds to drawableClass.prototype all the functions contained in Rac.drawableProtoFunctions. These are the functions shared by all drawable objects, for example draw() and debug().

Parameters:

Name	Type	Description
`drawableClass`	`class`	Class to setup with drawable functions

Angle(turn) → {Rac.Angle}

# | source: src/attachInstanceFunctions.js, line 141

Convenience function to create a new Angle. The created angle.rac is setup with this.

The function also contains additional methods and properties listed in instance.Angle.

Parameters:

Name	Type	Description
`turn`	`Number`	The turn value of the angle, in the range `[O,1)`

Example

let rac = new Rac()
let angle = rac.Angle(0.2)
angle.rac === rac // true

Arc(x, y, start, endopt, clockwiseopt) → {Rac.Arc}

# | source: src/attachInstanceFunctions.js, line 247

Convenience function to create a new Arc with the given primitive values. The created arc.rac is setup with this.

The function also contains additional methods and properties listed in instance.Arc.

Parameters:

Name	Type	Attributes	Default	Description
`x`	`Number`			The x coordinate for the arc center
`y`	`Number`			The y coordinate for the arc center
`start`	`Rac.Angle` \| `Number`			The start of the arc
`end`	`Rac.Angle` \| `Number`	<optional>	`null`	The end of the arc; when ommited or set to `null`, `start` is used instead
`clockwise`	`Boolean`	<optional>	`true`	The orientation of the arc

Example

let rac = new Rac()
let arc = rac.Arc(55, 77, 0.2)
arc.rac === rac // true

Bezier(startX, startY, startAnchorX, startAnchorY, endAnchorX, endAnchorY, endX, endY) → {Rac.Bezier}

# | source: src/attachInstanceFunctions.js, line 384

Convenience function that creates a new Bezier setup with this.

The function also contains additional methods and properties listed in instance.Bezier.

Parameters:

Name	Type	Description
`startX`	`Number`
`startY`	`Number`
`startAnchorX`	`Number`
`startAnchorY`	`Number`
`endAnchorX`	`Number`
`endAnchorY`	`Number`
`endX`	`Number`
`endY`	`Number`

Color(r, g, b, aopt) → {Rac.Color}

# | source: src/attachInstanceFunctions.js, line 38

Convenience function to create a new Color. The created color.rac is setup with this.

The function also contains additional methods and properties listed in instance.Color.

Parameters:

Name	Type	Attributes	Default
`r`	`Number`
`g`	`Number`
`b`	`Number`
`a`	`Number`	<optional>	`1`

Example

let rac = new Rac()
let color = rac.Color(0.2, 0.4, 0.6)
color.rac === rac // true

Composite(sequence) → {Rac.Composite}

# | source: src/attachInstanceFunctions.js, line 416

Convenience function to create a new Composite. The created composite.rac is setup with this.

Parameters:

Name	Type	Description
`sequence`	`Array`	An array of drawable objects to contain

Example

let rac = new Rac()
let composite = rac.Composite()
composite.rac === rac // true

equals(a, b) → {Boolean}

# | source: src/Rac.js, line 207

Returns true if the absolute distance between a and b is under equalityThreshold.

Parameters:

Name	Type	Description
`a`	`Number`	First number to compare
`b`	`Number`	Second number to compare

Fill(coloropt) → {Rac.Fill}

# | source: src/attachInstanceFunctions.js, line 91

Convenience function to create a new Fill. The created fill.rac is setup with this.

The function also contains additional methods and properties listed in instance.Fill.

Parameters:

Name	Type	Attributes	Default	Description
`color`	`Rac.Color`	<optional>	`null`

Example

let rac = new Rac()
let color = rac.Color(0.2, 0.4, 0.6)
let fill = rac.Fill(color)
fill.rac === rac // true

Point(x, y) → {Rac.Point}

# | source: src/attachInstanceFunctions.js, line 164

Convenience function to create a new Point. The created point.rac is setup with this.

The function also contains additional methods and properties listed in instance.Point.

Parameters:

Name	Type	Description
`x`	`Number`	The x coordinate
`y`	`Number`	The y coordinate

Example

let rac = new Rac()
let point = rac.Point(55, 77)
point.rac === rac // true

Ray(x, y, angle) → {Rac.Ray}

# | source: src/attachInstanceFunctions.js, line 189

Convenience function to create a new Ray with the given primitive values. The created ray.rac is setup with this.

The function also contains additional methods and properties listed in instance.Ray.

Parameters:

Name	Type	Description
`x`	`Number`
`y`	`Number`
`angle`	`Rac.Angle` \| `Number`

Example

let rac = new Rac()
let ray = rac.Ray(55, 77, 0.2)
ray.rac === rac // true

Segment(x, y, angle, length) → {Rac.Segment}

# | source: src/attachInstanceFunctions.js, line 217

Convenience function to create a new Segment with the given primitive values. The created segment.rac is setup with this.

The function also contains additional methods and properties listed in instance.Segment.

Parameters:

Name	Type	Description
`x`	`Number`
`y`	`Number`
`angle`	`Rac.Angle` \| `Number`
`length`	`Number`

Example

let rac = new Rac()
let segment = rac.Segment(55, 77, 0.2, 100)
segment.rac === rac // true

setupDrawer(p5Instance)

# | source: src/Rac.js, line 193

Sets the drawer for the instance. Currently only a p5.js instance is supported.

The drawer will also populate some classes with prototype functions relevant to the drawer. For p5.js this include apply functions for colors and style object, and vertex functions for drawable objects.

Parameters:

Name	Type	Description
`p5Instance`	`P5`

Stroke(weightnullable, coloropt) → {Rac.Stroke}

# | source: src/attachInstanceFunctions.js, line 65

Convenience function to create a new Stroke. The created stroke.rac is setup with this.

The function also contains additional methods and properties listed in instance.Stroke.

Parameters:

Name	Type	Attributes	Default	Description
`weight`	`Number`	<nullable>
`color`	`Rac.Color`	<optional>	`null`

Example

let rac = new Rac()
let color = rac.Color(0.2, 0.4, 0.6)
let stroke = rac.Stroke(2, color)
stroke.rac === rac // true

Style(strokeopt, fillopt) → {Rac.Style}

# | source: src/attachInstanceFunctions.js, line 115

Convenience function to create a new Style. The created style.rac is setup with this.

The function also contains additional methods and properties listed in instance.Style.

Parameters:

Name	Type	Attributes	Default	Description
`stroke`	`Rac.Stroke`	<optional>	`null`
`fill`	`Rac.Fill`	<optional>	`null`

Example

let rac = new Rac()
let color = rac.Color(0.2, 0.4, 0.6)
let style = rac.Style(rac.Stroke(2, color), rac.Fill(color))
style.rac === rac // true

Text(x, y, string, formatopt) → {Rac.Text}

# | source: src/attachInstanceFunctions.js, line 281

Convenience function to create a new Text. The created text.rac is setup with this.

The function also contains additional methods and properties listed in instance.Text.

Parameters:

Name	Type	Attributes	Default	Description
`x`	`Number`			The x coordinate location for the drawn text
`y`	`Number`			The y coordinate location for the drawn text
`string`	`String`			The string to draw
`format`	`Rac.Text.Format`	<optional>	`rac.Text.Format.topLeft`	The format for the drawn text

Example

let rac = new Rac()
let text = rac.Text(55, 77, 'black quartz')
text.rac === rac // true

TextFormat(hAlign, vAlign, angleopt, fontopt, sizeopt, hPaddingopt, vPaddingopt) → {Rac.Text.Format}

# | source: src/attachInstanceFunctions.js, line 310

Convenience function to create a new Text.Format. The created format.rac is setup with this.

The function also contains additional methods and properties listed in instance.Text.Format.

rac.Text.Format is an alias of this function.

Parameters:

Name	Type	Attributes	Default	Description
`hAlign`	`String`			The horizontal alignment, left-to-right; one of the values from `horizontalAlign`
`vAlign`	`String`			The vertical alignment, top-to-bottom; one of the values from `verticalAlign`
`angle`	`Rac.Angle`	<optional>	`rac.Angle.zero`	The angle towards which the text is drawn
`font`	`String`	<optional>	`null`	The font name
`size`	`Number`	<optional>	`null`	The font size
`hPadding`	`Number`	<optional>	`0`	The horizontal padding, left-to-right
`vPadding`	`Number`	<optional>	`0`	The vertical padding, top-to-bottom

Example

let rac = new Rac()
let format = rac.Text.Format('left', 'baseline', 0.2)
format.rac === rac // true

unitaryEquals(a, b) → {Boolean}

# | source: src/Rac.js, line 223

Returns true if the absolute distance between a and b is under unitaryEqualityThreshold.

Parameters:

Name	Type	Description
`a`	`Number`	First number to compare
`b`	`Number`	Second number to compare