API Docs Class: SkyDome

new SkyDome( [config])

A class for segmenting the sky dome and using it for calculations.

This class divides the sky dome into a series of segments or 'patches' and then stores a range of calculated shading and others values, as well as luminance/radiance distributions over each sky patch.

Parameters:

Name Type Argument Description

config

object

An optional configuration object.

Properties of `config`:

Name	Type	Argument	Description
`useColors`	boolean	<optional>	Whether or not to store colours for each sky patch.

Author:

drajmarsh

Classes

SkyPatchCache
SkyPatchIterator

Members

:number g_subdivisionCount <inner>

Stores the number of discreet subdivision patches in the current sky.

Type

number

Methods

calculateMetrics()

Calculates shading and sky factor values.

Returns:

Returns an object containing statistical obstruction data.

Type: object

callbackOnScaleChange( [callback])

Gets/sets the function called when the sky luminance distribution scale changes.

Parameters:

Name	Type	Argument	Description
`callback`	function	<optional>	An optional callback function.

Returns:

Returns the current callback or, if a value is given, returns this shading object to support method chaining.

Type: function | object

cancelCumulativeSky()

Cancels the current cumulative sky calculation, if in progress.

clearColors()

Clear all segment color data and release memory.

Returns:

Returns this sky dome instance to support method chaining.

Type: PD.SkyDome

clearShadingData()

Resets all shading data in the internal array to zero.

Returns:

Returns this sky dome instance to support method chaining.

Type: PD.SkyDome

copyShadingData( [result])

Copy the shading data array.

Parameters:

Name	Type	Argument	Description
`result`	Array.<number>	<optional>	An optional array to receive the shading data.

Returns:

An array of shading data, one value per sky segment.

Type: Array.<number>

copySkyPatchesToCanvas(canvas, projection [, shading])

Renders sky patch luminances and shading to the canvas.

Parameters:

Name	Type	Argument	Description
`canvas`	CanvasElement		The canvas element to render in.
`projection`	function \| PD.PROJECTION		A function for projecting altitude angles to radius, or a projection enumerator value.
`shading`	Array.<number>	<optional>	An optional array containing shading data for each sun patch, defaults to internal shading.

Returns:

Returns true if sky was rendered to canvas.

Type: boolean

copyToCanvas(canvas, projection [, shading])

Renders sky patch luminances and shading to the canvas.

Parameters:

Name	Type	Argument	Description
`canvas`	CanvasElement		The canvas element to render in.
`projection`	function \| PD.PROJECTION		A function for projecting altitude angles to radius, or a projection enumerator value.
`shading`	Array.<number>	<optional>	An optional array containing shading data for each sun patch, defaults to internal shading.

Returns:

Returns true if sky was rendered to canvas.

Type: boolean

copyToPolyMesh(mesh, center, radius [, outlines])

Copies the sky dome geometry to a mesh in model coordinates/units.

This method is used when adding a sky dome to a mesh that contains other geometry or more than one sky dome. It positions the sky dome hemisphere geometry at the given center and with the given radius. If you want to use a separate mesh per sky dome and independently position and size them, you should use the copyToTransformedPolyMesh() method instead.

Parameters:

Name	Type	Argument	Description
`mesh`	PD.PolyMesh		The mesh to update.
`center`	PD.Utils.VectorObject		The position of the sky dome in model coordinates.
`radius`	number		The radius of the sky dome in model units.
`outlines`	boolean	<optional>	Whether to include sky segment outlines, defaults to false.

Returns:

Returns an object containing statistical obstruction data.

Type: object

copyToTransformedPolyMesh(mesh [, outlines])

Copies the sky dome geometry to a mesh, centred at the origin and with unit radius.

This method is used when the mesh contains only this sky dome geometry and the host will scale and position it appropriately within the model. If you need to specify an absolute position, or add more than one sky dome to it, then you should use the copyToPolyMesh() method instead.

Parameters:

Name	Type	Argument	Description
`mesh`	PD.PolyMesh		The mesh to update.
`outlines`	boolean	<optional>	Whether to include sky segment outlines, defaults to false.

Returns:

Returns an object containing statistical obstruction data.

Type: object

copyToTransformedPolyMesh2D(mesh [, outlines])

Copies the sky dome geometry to a mesh as a flat diagram, centred at the origin and with unit radius.

Parameters:

Name	Type	Argument	Description
`mesh`	PD.PolyMesh		The mesh to update.
`outlines`	boolean	<optional>	Whether to include sky segment outlines, defaults to false.

Returns:

Returns an object containing statistical obstruction data.

Type: object

createNewSkyPatchCache(solar, jitter)

Creates a new detached cache for storing radiance/illuminance values for fast random-access or sequentially iterating through sky patches based on the current sky distribution.

NOTE: As this is a detached cache, you must manually call the update() method yourself to update this cache whenever the sky distribution is recalculated.

Parameters:

Name	Type	Description
`solar`	PD.SolarPosition	The solar position calculation object.
`jitter`	boolean	Whether or not to pseudo-randomly slightly perturb the patch center.

Returns:

Returns the horizontal illuminance cache object.

Type: object

fadeToBlack( [state])

Gets/sets whether or not to fade zero values to black or the minimum colour scale.

Parameters:

Name	Type	Argument	Description
`state`	boolean	<optional>	An optional boolean used to set the state of this value.

Returns:

Returns whether or not zero values are shown black or, if a value is given, this shading object to support method chaining.

Type: object

fitDistributionScale()

Fits the scale used to color the sky luminance distribution scale.

Returns:

Returns this shading object to support method chaining.

Type: object

generateCumulativeSky(solar, options)

Calculates the sky luminance values for the given Sun position.

Parameters:

Name Type Description

solar

PD.SolarPosition

The solar position calculation object.

options

object

A configuration object with the following properties.

Properties of `options`:

Name	Type	Description
`fromDay`	number	The day of the year to start calculating, inclusive (0 to 365/6).
`toDay`	number	The day of the year to end calculating, inclusive (0 to 365/6).
`fromTime`	number	The hour of each day to start calculating, in decimal hours (0.0 to 24.0).
`toTime`	number	The hour of each day to stop calculating, in decimal hours (0.0 to 24.0).
`timeStep`	number	The fractional hour for each calculation step (0 to 1).
`progress`	function	An optional callback to display progress.
`complete`	function	An optional callback when complete.

getAltitudeBandSegmentsFromDegrees(alt_degrees)

Retrieves the number of segments in the corresponding radial band at the given sky altitude.

Parameters:

Name	Type	Description
`alt_degrees`	number	The altitude angle, in decimal degrees (0 - 90).

Returns:

Returns the number of segments in that band (3 - 72), or zero if altitude outside range.

Type: number

getAltitudeBandSegmentsFromRadians(alt_radians)

Retrieves the number of segments in the corresponding radial band at the given sky altitude.

Parameters:

Name	Type	Description
`alt_radians`	number	The altitude angle, in radians (0 - PI/2).

Returns:

Returns the number of segments in that band (3 - 72), or zero if altitude outside range.

Type: number

getColors()

Returns the shading data array.

Returns:

An array of [r,g,b,a] color arrays, one per sky segment.

Type: Array.<Array.<number>>

getShadingData()

Retrieve the shading data array.

Returns:

An array of shading data, one value per sky segment.

Type: Array.<number>

getShadingMetrics()

Retrieves an object containing metrics for the last shading calculation.

This is a simple object containing the following properties.

Property	Type	Description
skyFactorLuminance	number	Fraction of the available sky luminance distribution not obstructed by shading.
skyFactorUniform	number	Fraction of the visible sky dome not obstructed by shading.

Returns:

Returns an object containing statistical obstruction data.

Type: object

getSkyParams()

Retrieves the calculated sky coefficients and distribution data.

This object stores all the information required to generate a Perez or CIE standard general sky distribution, and is passed around between different levels of the calculation functions.

This method returns an object with the following properties.

Property	Type	Description
iterator	object	The iterator used to calculate sky patch values.
sunAngles	Array	An [azi,alt] array containing the azimuth and altitude of the Sun in the calculated sky.
sunVector	Vector3	A 3D vector giving the direction towards the r of the Sun.
segmentVector	Vector3	A 3D vector giving the direction towards the centre of the current sky patch.
A, B, C, D, E	numbers	These are the five (5) Perez Sky Coefficients defining the current sky conditions.
totalDiffuseHorizontal	number	The total of all sky patch values, multiplied by the cosine of the altitude at their center.
resultsArray	Array	The array containing the calculated illuminance/radiance values for each sky patch.
maxValue	number	The highest calculated value of all the current sky patches.
exp_d_PI	number	Caches the value of exp(d * PI/2) to avoid continuous recalculation.
skyType	number	The CIE Std. Gen. Sky type for this sky (1-16, 17:WeatherData).

Returns:

Returns the object containing calculated sky parameters.

Type: object

getSkyPatchCSSColors( [shading])

Update and retrieve the current list of CSS colour strings for each sky segment.

Parameters:

Name	Type	Argument	Description
`shading`	Array.<number>	<optional>	An optional array containing shading data for each sun patch, defaults to internal shading.

Returns:

Returns an array of #RRGGBB color strings.

Type: Array.<string>

getSkyPatchCache()

Returns the internally linked horizontal illuminance cache, if it exists.

NOTE: To create and link this cache, you must have first called the useSkyPatchCache() method.

Returns:

Returns the horizontal illuminance cache object, or null if not yet created.

Type: object | null

getSkyPatchColor(index)

Get the shading colour at the given data segment.

Parameters:

Name	Type	Description
`index`	number	The numerical index of the data segment to set.

Returns:

Returns the [r,g,b[,a]] color array.

Type: Array.<number>

getSkyPatchContribution(index)

Get the sky distribution value at the given data segment.

Parameters:

Name	Type	Description
`index`	number	The numerical index of the data segment.

Returns:

Returns the sky distribution value at the given segment

Type: number

getSkyPatchContributionArray()

Get the array of sky distribution values for all segments.

Returns:

Returns the array of sky distribution values.

Type: Array

getSkyPatchCount()

Retrieves the number of subdivision patches in the current sky.

Returns:

Returns the number of subdivision patches in the current sky.

Type: number

getSkyPatchIndexByDegrees(azi_degrees, alt_degrees)

Retrieves the index of the sky segment in the shading data array.

Parameters:

Name	Type	Description
`azi_degrees`	number	The azimuth angle, in decimal degrees (0 - 360).
`alt_degrees`	number	The altitude angle, in decimal degrees (0 - 90).

Returns:

Returns the shading data array index.

Type: number

getSkyPatchIndexByRadians(azi_radians, alt_radians)

Retrieves the index of the sky segment in the shading data array.

Parameters:

Name	Type	Description
`azi_radians`	number	The azimuth angle, in radians (0 - 2*PI).
`alt_radians`	number	The altitude angle, in radians (0 - PI/2).

Returns:

Returns the shading data array index.

Type: number

getSkyPatchShading(index)

Get the shading value at the given sky segment.

Parameters:

Name	Type	Description
`index`	number	The numerical index of the sky segment to set.

hasShadingData()

Retrieves whether or not the shading data array is valid for the current sky.

Returns:

Returns true if the array of shading data matches the number of sky segments.

Type: boolean

isCumulative()

Retrieves whether or not the current sky distribution is a cumulative one.

Returns:

Returns true for cumulative, false for instantaneous.

Type: boolean

isDynamicSky()

Returns true if an update is required when Sun position changes.

A false value means that the sky distribution is static regardless of Sun position.

Returns:

Returns true if this sky distribution changes with solar position.

Type: boolean

isGeneratingCumulativeSky()

Determines whether or not a cumulative sky calculation is running.

Returns:

Returns true if a cumulative sky calculation is in progress.

Type: boolean

lockScale( [lock])

Gets/sets whether or not the scale is locked at its current value.

Parameters:

Name	Type	Argument	Description
`lock`	boolean	<optional>	An optional new lock state.

Returns:

Returns the current lock state or, if a value is given, returns this shading object to support method chaining.

Type: boolean | object

luminanceColorScaleAsHex(fraction)

Calculates a CSS sky colour based on the luminance scale.

Parameters:

Name	Type	Description
`fraction`	number	The fractional luminance value.

Returns:

Returns a CSS color string.

Type: string

newSkyPatchIterator()

Create a new shading segment iterator.

Returns:

Returns a new shading iterator object.

Type: object

perezSky( [perez])

Gets/sets the Perez sky object.

Parameters:

Name	Type	Argument	Description
`perez`	PD.PerezSky	<optional>	An optional new Perez sky object to use.

Returns:

Returns the current Perez sky object or, if a value is given, this shading object to support method chaining.

Type: PD.PerezSky | object

setColors(colors)

Copies the colour data to the internal shading colour array.

Parameters:

Name	Type	Description
`colors`	Array.<Array.<number>>	An array of [r,g,b,a] color arrays, one per sky segment.

Returns:

Returns true if the given data array is the same size as the shading color array and the data was copied, otherwise false.

Type: boolean

setShadingData(data)

Copies the shading data to the internal shading value array.

Parameters:

Name	Type	Description
`data`	Array.<number>	An array of shading values, one per sky segment.

Returns:

Returns true if the given data array is the same size as the shading array and the data was copied, otherwise false.

Type: boolean

setSkyCoefficients(A, B, C, D, E, solar)

Sets the 5 Perez sky coefficients and the Sun position.

Parameters:

Name	Type	Description
`A`	number	The first Perez sky coefficient: Horizon-Zenith Gradient.
`B`	number	The second Perez sky coefficient: Gradient Intensity.
`C`	number	The third Perez sky coefficient: Circumsolar Intensity.
`D`	number	The fourth Perez sky coefficient: Circumsolar Radius.
`E`	number	The fifth Perez sky coefficient: Backscattering Effect.
`solar`	PD.SolarPosition	The solar position calculation object with the current Sun angles.

Returns:

Returns true if distribution changed and update required.

Type: boolean

setSkyPatchColor(index, color)

Set the shading colour at the given data segment.

Parameters:

Name	Type	Description
`index`	number	The numerical index of the data segment to set.
`color`	Array.<number>	The [r,g,b[,a]] color array to set.

setSkyPatchShading(index, shading)

Set the shading value at the given sky segment.

Parameters:

Name	Type	Description
`index`	number	The numerical index of the sky segment to set.
`shading`	number	The shading value to set (0 to 1).

setSkyTypeAndUpdate(skyType, solar [, forceUpdate])

Sets the type of CIE Standard General Sky to generate.

This method also recalculates the sky distribution if the sky type or Sun position has changed. If you do not want to automatically update the sky, use the skyType(type) method.

Values for sky_type have the following meaning:

0: Means that no sky distribution is calculated.
1 to 15: Mean use the corresponding CIE Standard General Sky types.
16: Means using the older pre-2000 CIE Overcast Sky equations.
17: Means using the the current weather data and solar position to compute the sky type and Perez sky coefficients.
18: Means using Perez sky coefficients were previously set using setSkyCoefficients().

Parameters:

Name	Type	Argument	Description
`skyType`	number		The CIE Standard General Sky type (0 to 16).
`solar`	PD.SolarPosition		The solar position calculation object.
`forceUpdate`	boolean	<optional>	When set to true, the sky will always update.

Returns:

Returns true if distribution changed and update performed.

Type: boolean

setSubdivision(angle [, type])

Sets the angle and type of sky subdivision.

Parameters:

Name	Type	Argument	Description
`angle`	number		The sky segment angle, in decimal degrees (1.2 to 15.0).
`type`	number	<optional>	An optional sky subdivision method to use (0, 1, 2 or 3).

Returns:

Returns true if changed and update required.

Type: boolean

showCumulativeSky()

Copies any previously calculated cumulative sky to the sky distribution.

Returns:

Returns true if valid cumulative sky data was copies.

Type: boolean

skyDistributionFalseColor( [state])

Gets/sets whether or not to show sky luminance as false colour scale.

Parameters:

Name	Type	Argument	Description
`state`	boolean	<optional>	An optional false color scale state.

Returns:

Returns the current false color scale state or, if a value is given, this shading object to support method chaining.

Type: boolean | object

skyDistributionScale( [scale])

Gets/sets the scale used to color the sky luminance distribution.

Parameters:

Name	Type	Argument	Description
`scale`	number	<optional>	An optional luminance ratio scale.

Returns:

Returns the current luminance ratio scale or, if a value is given, returns this shading object to support method chaining.

Type: number | object

skyType( [sky_type])

Gets/sets the CIE Standard General Sky to use for luminance distribution.

If you wish to automatically recalculate the sky distribution if the sky type or Sun position has changed, use the this.setSkyTypeAndUpdate(type) method.

Parameters:

Name	Type	Argument	Description
`sky_type`	number	<optional>	An optional sky type index (0 to 16).

Returns:

Returns the current sky type index or, if a value is given, this shading object to support method chaining.

Type: number

subdivisionAngle( [angle])

Gets/sets the angle sky subdivision.

Parameters:

Name	Type	Argument	Description
`angle`	number	<optional>	An optional sky segment angle to set, in decimal degrees (1.2 to 15.0).

Returns:

Returns the sky segment angle in decimal degrees or, if a value is given, this shading object to support method chaining.

Type: number

updatePolyMeshColors(mesh, shading)

Updates the color buffer of the sky dome geometry to match sky conditions.

This methods pairs with the copyToTransformedPolyMesh() method in assuming that the mesh contains only the sky dome geometry, as created by that method, and quickly updates just the color buffer. This is because changes to the sky dome geometry are far less frequent than changes to the sky distribution or calculated shading as sky conditions change whenever the date, time, location (and therefore sun position) or sky type change.

Parameters:

Name	Type	Description
`mesh`	PD.PolyMesh	The mesh to update.
`shading`	Array.<number>	A shading mask array containing shading data for each sky segment.

Returns:

Returns an object containing statistical obstruction data.

Type: object

updateSkyDistribution(solar [, forceUpdate])

Calculates the sky luminance values for the given Sun position.

Parameters:

Name	Type	Argument	Description
`solar`	PD.SolarPosition		The solar position calculation object.
`forceUpdate`	boolean	<optional>	Some sky distributions don't change with Sun position. However to generate them in the first place, set this to true.

useColors( [state])

Gets/sets whether or not to store colours for each sky segment.

Parameters:

Name	Type	Argument	Description
`state`	boolean	<optional>	An optional boolean used to set the state of this value.

Returns:

Returns whether or not colors are being used or, if a value is given, this shading object to support method chaining.

Type: object

useIlluminance()

Retrieves whether or not illuminance is being used instead of radiance.

Returns:

Returns true for luminance, false for radiance.

Type: number

useNearestNeighborForDirectSun(state)

Whether or not to apportion direct radiation between the four nearest sky patches.

When set to false, this uses the actual solar disk to determine which sky patches receive what portion of direct solar radiation or luminance.

Parameters:

Name	Type	Description
`state`	boolean	When true, apportions between nearest four, otherwise uses solar disk.

Returns:

Returns this shading object to support method chaining.

Type: object

useSkyPatchCache(solar, jitter)

Embeds a cache for storing radiance/illuminance values for fast random-access or sequentially iterating through sky patches based on the current sky distribution.

This cache is internally linked to this shading instance and is therefore updated automatically whenever the sky distribution is recalculated.

Parameters:

Name	Type	Description
`solar`	PD.SolarPosition	The solar position calculation object.
`jitter`	boolean	Whether or not to pseudo-randomly slightly perturb the patch center.

Returns:

Returns the horizontal illuminance cache object.

Type: object

weatherData( [weather])

Gets/sets the annual hourly weather data object.

Parameters:

Name	Type	Argument	Description
`weather`	PD.WeatherData	<optional>	An optional new weather data set to use.

Returns:

Returns the current weather data object or, if a value is given, this shading object to support method chaining.

Type: PD.WeatherData | PD.SkyDome

getProjectRadiusFunction(projection) <static>

Retrieves the conversion function associated with a projection.

Parameters:

Name	Type	Description
`projection`	PD.PROJECTION	The projection enumerator.

Returns:

Returns the associated function, defaulting to equidistant.

Type: function

interpolateProjectionFactory(projectFrom, projectTo) <static>

A factory function that returns an object containing two functions, one (set) for updating the transition fraction and the other (convert) for assigning and doing the actual conversion.

Parameters:

Name	Type	Description
`projectFrom`	PD.PROJECTION	The current projection enumerator.
`projectTo`	PD.PROJECTION	The new projection enumerator to animate to.

Returns:

Returns an object with set(fraction) and convert(alt) properties.

Type: object

projectEquidistant(alt) <static>

Converts an altitude angle into a linearly projected chart radius.

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Parameters:

Name	Type	Description
`alt`	number	The chart altitude in degrees (-90 to 90).

Returns:

Returns a fractional radius (0 to 1).

Type: number

projectSpherical(alt) <static>

Converts an altitude angle into a spherically projected chart radius.

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Parameters:

Name	Type	Description
`alt`	number	The chart altitude in degrees (-90 to 90).

Returns:

Returns a fractional radius (0 to 1).

Type: number

projectStereographic(alt) <static>

Converts an altitude angle into a stereographic projected chart radius.

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Parameters:

Name	Type	Description
`alt`	number	The chart altitude in degrees (-90 to 90).

Returns:

Returns a fractional radius (0 to 1).

Type: number

assignDirectSolarByDisk(params, direct_beam, array) <inner>

Assigns the given direct solar data to nearest sky segments.

Parameters:

Name	Type	Description
`params`	CIESkyParams	The current CIE sky parameters.
`direct_beam`	number	The direct irradiance/illuminance value to assign to sky patches.
`array`	Array	The array to add the direct value to.

assignDirectSolarByQuad(params, direct_beam, array) <inner>

Assigns the given direct solar data to nearest sky segments.

Parameters:

Name	Type	Description
`params`	CIESkyParams	The current CIE sky parameters.
`direct_beam`	number	The direct irradiance/illuminance value to assign to sky patches.
`array`	Array	The array to add the direct value to.

calculateCircumferenceIncrement(inc) <inner>

Used to keep circle line circular at large angle increments.

This is required for the various bands to line up when the number of segments per band changes with altitude.

Parameters:

Name	Type	Description
`inc`	number	The azimuth band increment value.

Returns:

Returns the increment for each band segment.

Type: number

calculateEqualAngleSky(angle) <inner>

Sets the sky subdivision angle and recalculates segmentation.

In this subdivision method, the sky dome is divided by equal altitude and azimuth angles, resulting in the same number of radial segments in each altitude band. This means that sky patches nearer the zenith are much smaller than those at the horizon, but this greatly simplifies the process of contouring the data.

Parameters:

Name	Type	Description
`angle`	number	The spherical angle to segment the sky, in decimal degrees (1.2 to 15).

calculateEqualAreaSky(angle) <inner>

Sets the sky subdivision angle and recalculates segmentation.

This subdivision method divides the sky dome into equal altitude bands based on the given angle and then varies the number of radial segments in each band to ensure all sky patches represent a similar solid angle. In this method there is no single sun patch at the zenith, but the altitude is evenly divided.

Parameters:

Name	Type	Description
`angle`	number	The spherical angle to segment the sky, in decimal degrees (1.2 to 15).

calculateRelativeLuminance(zen_angle, sun_angle) <inner>

Calculates the relative luminance of a point on the sky dome.

Ref: ISO 15469:2004(E) / CIE S 011/E:2003: Spatial Distribution of Daylight - CIE Standard General Sky

Parameters:

Name	Type	Description
`zen_angle`	number	Angle between sky patch center and Zenith, in radians.
`sun_angle`	number	Angle between sky patch center and the Sun, in radians.

Returns:

Returns the ratio of segment luminance to zenith luminance.

Type: boolean

calculateTregenzaSky(angle) <inner>

Sets the sky subdivision angle and recalculates segmentation.

This subdivision method is based on the 145 sky segments proposed by Tregenza which, similar to the equal-area approach, divides the sky dome into equal altitude bands of 12 degrees each and then varies the number of radial segments in each band to ensure all sky patches represent a similar solid angle. The difference is that Tregenza's method uses a single sky patch at the zenith and more detailed sky subdivision is only possible by subdividing each of the original 145 sky segments.

Parameters:

Name	Type	Description
`angle`	number	The spherical angle to segment the sky, in decimal degrees (1.2 to 15).

callbackProcessSkyPatch(iterator, params) <inner>

Callback function invoked by sky segment iterator when calculating sky luminance.

Ref: ISO 15469:2004(E) / CIE S 011/E:2003: Spatial Distribution of Daylight - CIE Standard General Sky

NOTE: This callback references the g_skyParams property, which must be set first by invoking the updateSkyDistribution() method, and then updates entries in the g_skyDistribution array.

Parameters:

Name	Type	Description
`iterator`	SkyPatchIterator	The SkyPatchIterator object.
`params`	CIESkyParams	The CIE sky parameters.

callbackProcessSkyPatchAndCache(iterator, params) <inner>

Callback function invoked by sky segment iterator when calculating sky luminance.

Ref: ISO 15469:2004(E) / CIE S 011/E:2003: Spatial Distribution of Daylight - CIE Standard General Sky

NOTE: This callback references the g_skyParams property, which must be set first by invoking the updateSkyDistribution() method, and then updates entries in the g_skyDistribution array.

Parameters:

Name	Type	Description
`iterator`	SkyPatchIterator	The SkyPatchIterator object.
`params`	CIESkyParams	The CIE sky parameters.

fastGetShadingArrayIndex(azi_degrees, alt_degrees) <inner>

Calculates the sky segment index from a polar angle.

NOTE: This function requires that both the azimuth and altitude angles be in decimal degrees, and that the azimuth is in the range 0 to 360 and the altitude in the range -90 to 90.

Parameters:

Name	Type	Description
`azi_degrees`	number	The azimuth angle, in decimal degrees (0 - 360).
`alt_degrees`	number	The altitude angle, in decimal degrees (0 - 90).

Returns:

Returns the shading data array index.

Type: number

luminanceColorScaleYellowBlue(fraction, result) <inner>

Calculates a sky colour based on the luminance scale.

Parameters:

Name	Type	Description
`fraction`	number	The fractional luminance value.
`result`	Array	The [r,g,b,a] array to receive the colour values.

Returns:

Returns the results array.

Type: Array

Class: SkyDome

new SkyDome( [config])

Parameters:

Properties of config:

Classes

Members

g_subdivisionCount <inner>

Type

Methods

calculateMetrics()

Returns:

callbackOnScaleChange( [callback])

Parameters:

Returns:

cancelCumulativeSky()

clearColors()

Returns:

clearShadingData()

Returns:

copyShadingData( [result])

Parameters:

Returns:

copySkyPatchesToCanvas(canvas, projection [, shading])

Parameters:

Returns:

copyToCanvas(canvas, projection [, shading])

Parameters:

Returns:

copyToPolyMesh(mesh, center, radius [, outlines])

Parameters:

Returns:

copyToTransformedPolyMesh(mesh [, outlines])

Parameters:

Returns:

copyToTransformedPolyMesh2D(mesh [, outlines])

Parameters:

Returns:

createNewSkyPatchCache(solar, jitter)

Parameters:

Returns:

fadeToBlack( [state])

Parameters:

Returns:

fitDistributionScale()

Returns:

generateCumulativeSky(solar, options)

Parameters:

Properties of options:

getAltitudeBandSegmentsFromDegrees(alt_degrees)

Parameters:

Returns:

getAltitudeBandSegmentsFromRadians(alt_radians)

Parameters:

Returns:

getColors()

Returns:

getShadingData()

Returns:

getShadingMetrics()

Returns:

getSkyParams()

Returns:

getSkyPatchCSSColors( [shading])

Parameters:

Returns:

getSkyPatchCache()

Returns:

getSkyPatchColor(index)

Parameters:

Returns:

getSkyPatchContribution(index)

Parameters:

Returns:

getSkyPatchContributionArray()

Returns:

getSkyPatchCount()

Returns:

getSkyPatchIndexByDegrees(azi_degrees, alt_degrees)

Parameters:

Returns:

Properties of `config`:

Properties of `options`: