/**
* @module esri/renderers/VisualVariablesMixin
* @mixin
*/




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//
// Properties
//
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/**
* Visual variables define the parameters
* for data-driven geographic visualizations of numeric data. They allow you to
* easily map continuous ramps of {@link module:esri/renderers/Renderer~ColorVisualVariable color}, {@link module:esri/renderers/Renderer~SizeVisualVariable size},
* {@link module:esri/renderers/Renderer~OpacityVisualVariable opacity}, and/or {@link module:esri/renderers/Renderer~RotationVisualVariable rotation} to minimum and maximum data values
* of one of the layer's numeric attribute fields.
*
* Visual variables can primarily be used in two ways.
*
* #### 1. Thematic mapping
*
* Visual variables allow you to easily create stunning visualizations
* based on thematic attributes (e.g. population, education, rank, money, magnitude, etc.) in
* either 2D or 3D. This is accomplished by mapping data values from a numeric field attribute
* to color, size, and/or opacity values.
* The renderer then takes over and re-sizes or shades features based on the value of the given
* field and its position relative to the minimum and maximum values. The sample below uses
* three visual variables (size, color, and opacity).
*
* [![renderer-unique-vv](../assets/img/apiref/renderers/renderer-unique-vv.png)](../sample-code/visualization-multivariate-2d/index.html)
*
* #### 2. Mapping real-world sizes
*
* The {@link module:esri/renderers/Renderer~SizeVisualVariable size} visual variable can be used to
* visualize the true sizes of features (e.g. tree canopy, road width, building height, etc.)
* based on their size in the real world. This can be particularly powerful when working in a 3D
* {@link module:esri/views/SceneView}. The image below shows a layer of building footprints
* that uses visual variables to extrude each feature to the true height of the buildings
* based on data stored in an attribute field.
*
* [![renderer-vv-rw](../assets/img/samples/2-extrude-height.png)](../sample-code/visualization-buildings-3d/index.html)
*
* The `visualVariables` property of the renderer is an array of objects called "visual variables".
* Each object must indicate
* the type of visual variable to apply (e.g. color, size, opacity, rotation), the numeric
* field from which to drive the visualization, and the ramp of visual values to map to the data.
* The following list identifies each visual variable type and provides a link to the specification table
* of each.
*
* Type | Object Specification | Legend Example
* -----|----------------------|---------------
* color | {@link module:esri/renderers/Renderer~ColorVisualVariable ColorVisualVariable} | ![legend-color-vv](../assets/img/apiref/renderers/legend-color-vv.png)
* size | {@link module:esri/renderers/Renderer~SizeVisualVariable SizeVisualVariable} | ![legend-color-vv](../assets/img/apiref/renderers/legend-size-vv.png)
* opacity | {@link module:esri/renderers/Renderer~OpacityVisualVariable OpacityVisualVariable} | ![legend-color-vv](../assets/img/apiref/renderers/legend-opacity-vv.png)
* rotation | {@link module:esri/renderers/Renderer~RotationVisualVariable RotationVisualVariable} | -
*
* See the [Visualize features with realistic 3D symbols](../sample-code/visualization-trees-realistic/index.html)
* for an example of using multiple visual variables to visualize your data.
*
* @name visualVariables
* @memberof module:esri/renderers/VisualVariablesMixin
* @type {Object[]}
*
* @see [Creating visualizations manually](../guide/creating-visualizations-manually/index.html)
* @see [Visualization overview](../guide/visualization-overview/index.html)
*/





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//
// Public methods
//
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/**
* Indicates if the renderer has defined [visualVariables](#visualVariables).
*
* @method hasVisualVariables
* @memberof module:esri/renderers/VisualVariablesMixin
* @ignore
*
* @param   {string} type - can be one of: size, color, opacity, rotation (optional)
* @param   {(Object|boolean)} target - can be: false or "outline" (optional)
* @return {boolean} If `true`, then the renderer has at least one visual variable.
*/







/**
* Returns the visual variables of the specified type.
*
* @method getVisualVariablesForType
* @memberof module:esri/renderers/VisualVariablesMixin
* @ignore
*
* @param {string} type - The type of visual variables desired.
*                        <br><br>**Known Values:** color | size | opacity | rotation
* @return {Object[]} Returns the visual variables associated with the input `type`.
*
* @see [visualVariables](#visualVariables)
* @example
* var colorVisVars = renderer.getVisualVariablesForType("color");
*/






/**
* Returns the symbol size (in pixels) for the input graphic.
*
* @method getSize
* @memberof module:esri/renderers/VisualVariablesMixin
* @ignore
*
* @param {module:esri/Graphic} graphic - The graphic for which you want
* to calculate the symbol size.
*
* @return {number} The size of the input graphic's symbol in pixels.
*/






/**
* Returns the color of the symbol used to render the input Graphic.
*
* @method getColor
* @memberof module:esri/renderers/VisualVariablesMixin
* @ignore
*
* @param {module:esri/Graphic} graphic - The graphic from which to get the symbol's color.
*
* @return {module:esri/Color} The color used in rendering the input graphic.
*/





/**
* Returns the opacity value for the specified graphic.
*
* @method getOpacity
* @memberof module:esri/renderers/VisualVariablesMixin
* @ignore
*
* @param {module:esri/Graphic} graphic - The graphic from which to get an opacity value.
*
* @return {number} The opacity value of the input graphic.
*/






/**
* Returns the rotation angle used in rendering the input graphic.
*
* @method getRotationAngle
* @memberof module:esri/renderers/VisualVariablesMixin
* @ignore
*
* @param {module:esri/Graphic} graphic - The graphic from which to get a rotation value.
*
* @return {number} The rotation angle of the symbol used to render the input graphic.
*/





/**
* Returns the symbol used by the input graphic.
*
* @method getSymbol
* @memberof module:esri/renderers/VisualVariablesMixin
* @ignore
*
* @param {module:esri/Graphic} graphic - A graphic from which to get a symbol.
*
* @return {module:esri/symbols/Symbol} Returns the symbol used to render the input graphic.
*/