Range

Range (from scenerystack/dot) is a simple [min, max] interval. It's most commonly seen as the range option passed to a NumberProperty, which sliders and number spinners use for their bounds, but it's a general-purpose interval type used anywhere a valid numeric interval needs a name.

import { Range } from 'scenerystack/dot';

const temperatureRange = new Range( 0, 100 );

temperatureRange.contains( 37 );          // true
temperatureRange.constrainValue( 150 );   // 100 — clamps into the range
temperatureRange.getCenter();             // 50

Constructing a range

The constructor takes min and max directly: new Range( min, max ). Both min and max are also settable properties (range.min = 10), with an internal assertion that min <= max is maintained at all times.

Static	Meaning
Range.EVERYTHING	(-Infinity, Infinity)
Range.NOTHING	(Infinity, -Infinity) — an inverted, "empty" range

Methods

Method	Effect
getLength()	max - min
getCenter()	(min + max) / 2
contains( value )	Whether value is within [min, max], inclusive
containsRange( range )	Whether this range fully contains another range
intersects( range ) / intersectsExclusive( range )	Whether two ranges overlap
constrainValue( value )	Clamp a value into [min, max]
getNormalizedValue( value ) / expandNormalizedValue( t )	Map a value to/from [0, 1] within the range
union( range ) / includeRange( range )	Smallest range containing both — immutable / mutable pair
intersection( range ) / constrainRange( range )	Largest range contained by both — immutable / mutable pair
shifted( n )	New range with both endpoints offset by n
times( value ) / multiply( value )	Scale both endpoints — immutable / mutable pair
addValue( n )	Mutable: expand min/max, if needed, to include n
withValue( n )	Immutable counterpart of addValue
copy()	Clone
equals( range ) / equalsEpsilon( range, epsilon )	Comparison

Common use: NumberProperty validation

import { NumberProperty } from 'scenerystack/axon';
import { Range } from 'scenerystack/dot';

const temperatureProperty = new NumberProperty( 20, {
  range: new Range( 0, 100 )
} );

NumberProperty uses its range option both to validate assignments in assertion-enabled builds and to give UI components (like sliders) their bounds automatically — see NumberProperty.

defaultValue belongs to RangeWithValue, not Range

Reaching for range.defaultValue on a plain Range throws immediately — that field only exists on the related RangeWithValue subclass (also exported from scenerystack/dot), which pairs a range with a starting value for controls that need one (e.g. a reset-able slider). If you need a default alongside min/max, reach for RangeWithValue instead of trying to bolt one onto Range.

Related

• NumberProperty — the most common consumer of Range, via its range option.
• Bounds2 — bounds.xRange / bounds.yRange expose each axis of a bounds as a Range.
• Utils — clamp() is the free-function equivalent of range.constrainValue() when you don't have a Range object handy.