Rac. RayControl

Control that allows the selection of a value with a knob that slides through the segment of a Ray.

Uses a Ray as anchor, which defines the position where the control is drawn.

length defines the length of the segment in the anchor ray which is available for user interaction. Within this segment the user can slide the control knob to select a value.

Constructor

new RayControl(rac, value, length)

Creates a new RayControl instance with the starting value and the interactive length.

Parameters:
Name Type Description
rac Rac

Instance to use for drawing and creating other objects

value number

The initial value of the control, in the [0,1] range

length number

The length of the anchor ray available for user interaction

Extends

Members

(nullable) anchor :Rac.Ray

Ray to which the control will be anchored. Defines the location where the control is drawn.

Along with length defines the segment available for user interaction.

The control cannot be drawn or selected until this property is set.

Default Value:
  • null

endLimit :number

Maximum value that can be selected through user interaction.

Overrides:
Default Value:
  • 1

length :number

Length of the anchor ray available for user interaction.

markers :Array.<number>

Collection of values at which visual markers are drawn.

Overrides:
Default Value:
  • []

projectionEnd :number

Projected value to use when value is 1.

Overrides:
Default Value:
  • 1

projectionStart :number

Projected value to use when value is 0.

Overrides:
Default Value:
  • 0

rac :Rac

Instance of Rac used for drawing and passed along to any created object.

Overrides:

startLimit :number

Minimum value that can be selected through user interaction.

Overrides:
Default Value:
  • 0

style :Rac.Stroke|Rac.Fill|Rac.StyleContainer

Style to apply when drawing. This style gets applied after rac.controller.controlStyle.

Overrides:
Default Value:
  • null

value :number

Current selected value, in the range [0,1].

May be further constrained to [startLimit,endLimit].

Overrides:

Methods

addMarkerAtCurrentValue()

Adds a marker at the current value.

Overrides:

affixAnchor() → {Rac.Segment}

Returns a new Segment produced with the anchor ray with length, to be persisted during user interaction.

An error is thrown if anchor is not set.

Overrides:

distance() → {number}

Returns the distance between the anchor ray start and the control knob.

Equivalent to the control value projected to the range [0,length].

draw()

Draws the current state.

Overrides:

drawSelection(pointerCenter, fixedAnchor, pointerToKnobOffset)

Draws the selection state along with pointer interaction visuals.

Overrides:
Parameters:
Name Type Description
pointerCenter Rac.Point

The position of the user pointer

fixedAnchor Rac.Segment

Segment produced with affixAnchor when user interaction started

pointerToKnobOffset Rac.Segment

A Segment that represents the offset from pointerCenter to the control knob when user interaction started.

isSelected() → {boolean}

Returns true when this control is the currently selected control.

Overrides:

knob() → (nullable) {Rac.Point}

Returns a Point at the center of the control knob.

When anchor is not set, returns null instead.

Overrides:

projectedValue() → {number}

Returns value projected into the range [projectionStart,projectionEnd].

By default the projection range is [0,1], in which case value and projectedValue() are equal.

Projection ranges with a negative direction (E.g. [50,30], when projectionStart is greater that projectionEnd) are supported. As value increases, the projection returned decreases from projectionStart until reaching projectionEnd.

E.g.

For a control with a projection range of [100,200]
+ when value is 0,   projectionValue() is 100
+ when value is 0.5, projectionValue() is 150
+ when value is 1,   projectionValue() is 200

For a control with a projection range of [50,30]
+ when value is 0,   projectionValue() is 50
+ when value is 0.5, projectionValue() is 40
+ when value is 1,   projectionValue() is 30
Overrides:

setLimitsWithInsets(startInset, endInset)

Sets both startLimit and endLimit with the given insets from 0 and 1, correspondingly.

E.g.

control.setLimitsWithInsets(0.1, 0.2)
// sets startLimit as 0.1
// sets endLimit   as 0.8
Overrides:
Parameters:
Name Type Description
startInset number

The inset from 0 to use for startLimit

endInset number

The inset from 1 to use for endLimit

setLimitsWithLengthInsets(startInset, endInset)

Sets both startLimit and endLimit with the given insets from 0 and length, correspondingly, both projected in the [0,length] range.

E.g.

// For a RayControl with length of 100
control.setLimitsWithLengthInsets(10, 20)
// sets startLimit as 0.1 which is at length 10
// sets endLimit   as 0.8 which is at length 80 from 100
//   10 inset from 0 = 10
//   20 inset from 100 = 80
Parameters:
Name Type Description
startInset number

The inset from 0 in the range [0,length] to use for startLimit

endInset number

The inset from length in the range [0,length] to use for endLimit

setValueWithLength(lengthValue)

Sets value using the projection of lengthValue in the [0,length] range.

Parameters:
Name Type Description
lengthValue number

The length at which to set the current value

updateWithPointer(pointerKnobCenter, fixedAnchor)

Updates value using pointerKnobCenter in relation to fixedAnchor.

value is always updated by this method to be within [0,1] and [startLimit,endLimit].

Overrides:
Parameters:
Name Type Description
pointerKnobCenter Rac.Point

The position of the knob center as interacted by the user pointer

fixedAnchor Rac.Segment

Segment produced with affixAnchor when user interaction started