Rac

# | source: src/Rac.js, line 21

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 21

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 327

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 as example '1057-94b059d'

(static, constant) dated :String

# | source: src/Rac.js, line 343

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 as example '2022-10-13T23:06:12.500Z'

(static, constant) TAU :Number

# | source: src/Rac.js, line 358

Tau, equal to Math.PI * 2.

See Tau Manifesto.

(static, constant) utils :utils

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

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

Also available through Rac#utils.

(static, constant) version :String

# | source: src/Rac.js, line 314

Version of the class. Same as the version used for the npm package.

Example
Rac.version // returns as example '1.2.1'

(constant) build :String

# | source: src/Rac.js, line 40

Build of the instance, same as Rac.build.

Example
rac.build // returns as example '1057-94b059d'

controller

# | source: src/Rac.js, line 175

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 52

Date of the build of the instance, same as Rac.dated.

Example
rac.dated // returns as example '2022-10-13T23:06:12.500Z'

(nullable) drawer :Object

# | source: src/Rac.js, line 154

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 84

Value used to determine equality between two numeric values. Used for values that tend to be integers, like screen coordinates. Used by Rac#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 142

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 103

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

Equality logic is the same as Rac#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 114

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

Also available through Rac.utils.

(constant) version :String

# | source: src/Rac.js, line 28

Version of the instance, same as Rac.version.

Example
rac.version // returns as example '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 144

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.

See also:
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(1/2)
angle.rac === rac // true

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

# | source: src/attachInstanceFunctions.js, line 258

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.

See also:
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, 1/4)
arc.rac === rac // true

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

# | source: src/attachInstanceFunctions.js, line 392

Convenience function that creates a new Bezier setup with this.

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

See also:
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 33

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.

See also:
Parameters:
Name Type Attributes Default Description
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

equals(a, b) → {Boolean}

# | source: src/Rac.js, line 202

Returns true if the absolute distance between a and b is under Rac#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 90

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.

See also:
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 169

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.

See also:
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 196

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.

See also:
Parameters:
Name Type Description
x Number
y Number
angle Rac.Angle | Number
Example
let rac = new Rac()
let ray = rac.Ray(55, 77, 1/2)
ray.rac === rac // true

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

# | source: src/attachInstanceFunctions.js, line 226

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.

See also:
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, 1/2, 100)
segment.rac === rac // true

setupDrawer(p5Instance)

# | source: src/Rac.js, line 188

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 62

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.

See also:
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 116

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.

See also:
  • 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 294

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.

See also:
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) → {Rac.Text.Format}

# | source: src/attachInstanceFunctions.js, line 325

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.

See also:
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
Example
let rac = new Rac()
let format = rac.Text.Format('left', 'baseline', 1/8)
format.rac === rac // true

unitaryEquals(a, b) → {Boolean}

# | source: src/Rac.js, line 218

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

Parameters:
Name Type Description
a Number

First number to compare
b Number

Second number to compare