require(["esri/rest/support/AlgorithmicColorRamp"], (AlgorithmicColorRamp) => { /* code goes here */ });
import AlgorithmicColorRamp from "@arcgis/core/rest/support/AlgorithmicColorRamp.js";
esri/rest/support/AlgorithmicColorRamp
Creates a color ramp for use in a raster renderer. The algorithmic color ramp is defined by specifying two colors and the algorithm used to traverse the intervening color spaces.
There are three algorithms that can be used to define the color values between the from and to colors: 'cie-lab', 'hsv', and 'lab-lch'. There is very little difference between these algorithms when the from and the to colors are of the same or very similar hues. However, when the hues for the from and to colors are different (Hue is different by 40 or more on a 0-360 scale), the algorithms produce different results. The 'hsv' algorithm traverses the hue difference in a purely linear fashion, resulting in a bright ramp where all intermediate colors are represented. For instance, a ramp from red to green would include orange, yellow, and yellow-green. The 'cie-lab' and 'lab-lch' produce a more blended result. Thus, a ramp from dark green to orange would not contain a bright yellow, but instead a more brown and green-gold or green-brown intermediate color. The advantage of the 'cie-lab' algorithm is that the colors of the ramp are visually equidistant, which can produce a better ramp.
Constructors
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Parameterproperties Objectoptional
See the properties for a list of all the properties that may be passed into the constructor.
Property Overview
| Name | Type | Summary | Class |
|---|---|---|---|
The algorithm used to generate the colors between the | AlgorithmicColorRamp | ||
The name of the class. | Accessor | ||
The first color in the color ramp. | AlgorithmicColorRamp | ||
The last color in the color ramp. | AlgorithmicColorRamp | ||
A string value representing the color ramp type. | AlgorithmicColorRamp |
Property Details
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The algorithm used to generate the colors between the
fromColorandtoColor. Each algorithm uses different methods for generating the intervening colors.Possible Value Description cie-lab Blends the from and to colors without traversing the intervening hue space. lab-lch The hue, saturation, value (hsv) algorithm is a linear traverse of colors between pairs: Color 1 H to Color 2 H, Color 1 S to Color 2 S, and Color 1 V to Color 2 V. hsv The lab-lch algorithm is very similar to the cie-lab but does not seek the shortest path between colors. Possible Values:"cie-lab" |"lab-lch" |"hsv"
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type
Propertytype Stringreadonly -
A string value representing the color ramp type.
For AlgorithmicColorRamp the type is always "algorithmic".
- Default Value:"algorithmic"
Method Overview
| Name | Return Type | Summary | Class |
|---|---|---|---|
Adds one or more handles which are to be tied to the lifecycle of the object. | Accessor | ||
Creates a deep clone of this object. | AlgorithmicColorRamp | ||
Creates a new instance of this class and initializes it with values from a JSON object generated from an ArcGIS product. | ColorRamp | ||
Returns true if a named group of handles exist. | Accessor | ||
Removes a group of handles owned by the object. | Accessor | ||
Converts an instance of this class to its ArcGIS portal JSON representation. | ColorRamp |
Method Details
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Inherited from Accessor
Since: ArcGIS Maps SDK for JavaScript 4.25Accessor since 4.0, addHandles added at 4.25. -
Adds one or more handles which are to be tied to the lifecycle of the object. The handles will be removed when the object is destroyed.
// Manually manage handles const handle = reactiveUtils.when( () => !view.updating, () => { wkidSelect.disabled = false; }, { once: true } ); this.addHandles(handle); // Destroy the object this.destroy();ParametershandleOrHandles WatchHandle|WatchHandle[]Handles marked for removal once the object is destroyed.
groupKey *optionalKey identifying the group to which the handles should be added. All the handles in the group can later be removed with Accessor.removeHandles(). If no key is provided the handles are added to a default group.
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clone
Methodclone(){AlgorithmicColorRamp} -
Creates a deep clone of this object.
ReturnsType Description AlgorithmicColorRamp A deep clone of the AlgorithmicColorRamp instance that invoked this method.
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Creates a new instance of this class and initializes it with values from a JSON object generated from an ArcGIS product. The object passed into the input
jsonparameter often comes from a response to a query operation in the REST API or a toJSON() method from another ArcGIS product. See the Using fromJSON() topic in the Guide for details and examples of when and how to use this function.Parameterjson ObjectA JSON representation of the instance in the ArcGIS format. See the ArcGIS REST API documentation for examples of the structure of various input JSON objects.
Returns
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hasHandles
InheritedMethodhasHandles(groupKey){Boolean}Inherited from AccessorSince: ArcGIS Maps SDK for JavaScript 4.25Accessor since 4.0, hasHandles added at 4.25. -
Returns true if a named group of handles exist.
ParametergroupKey *optionalA group key.
ReturnsType Description Boolean Returns trueif a named group of handles exist.Example// Remove a named group of handles if they exist. if (obj.hasHandles("watch-view-updates")) { obj.removeHandles("watch-view-updates"); }
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Inherited from Accessor
Since: ArcGIS Maps SDK for JavaScript 4.25Accessor since 4.0, removeHandles added at 4.25. -
Removes a group of handles owned by the object.
ParametergroupKey *optionalA group key or an array or collection of group keys to remove.
Exampleobj.removeHandles(); // removes handles from default group obj.removeHandles("handle-group"); obj.removeHandles("other-handle-group");
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toJSON
InheritedMethodtoJSON(){Object}Inherited from ColorRamp -
Converts an instance of this class to its ArcGIS portal JSON representation. See the Using fromJSON() guide topic for more information.
ReturnsType Description Object The ArcGIS portal JSON representation of an instance of this class.