MGLCircleStyleLayer


@interface MGLCircleStyleLayer : MGLVectorStyleLayer

An MGLCircleStyleLayer is a style layer that renders one or more filled circles on the map.

Use a circle style layer to configure the visual appearance of point or point collection features in vector tiles loaded by an MGLVectorSource object or MGLPointAnnotation, MGLPointFeature, MGLPointCollection, or MGLPointCollectionFeature instances in an MGLShapeSource object.

A circle style layer renders circles whose radii are measured in screen units. To display circles on the map whose radii correspond to real-world distances, use many-sided regular polygons and configure their appearance using an MGLFillStyleLayer object.

You can access an existing circle style layer using the -[MGLStyle layerWithIdentifier:] method if you know its identifier; otherwise, find it using the MGLStyle.layers property. You can also create a new circle style layer and add it to the style using a method such as -[MGLStyle addLayer:].

Example

let layer = MGLCircleStyleLayer(identifier: "circles", source: population)
layer.sourceLayerIdentifier = "population"
layer.circleColor = MGLStyleValue(rawValue: .green)
layer.circleRadius = MGLStyleValue(interpolationMode: .exponential,
                                   cameraStops: [12: MGLStyleValue(rawValue: 2),
                                                 22: MGLStyleValue(rawValue: 180)],
                                   options: [.interpolationBase: 1.75])
layer.circleOpacity = MGLStyleValue(rawValue: 0.7)
layer.predicate = NSPredicate(format: "%K == %@", "marital-status", "married")
mapView.style?.addLayer(layer)


                    
                    
                    -initWithIdentifier:source:

Returns a circle style layer initialized with an identifier and source.

After initializing and configuring the style layer, add it to a map view’s style using the -[MGLStyle addLayer:] or -[MGLStyle insertLayer:belowLayer:] method.

Declaration

Objective-C

- (nonnull instancetype)initWithIdentifier:(nonnull NSString *)identifier
                                    source:(nonnull MGLSource *)source;

Swift

init(identifier: String, source: MGLSource)

Parameters

`identifier`	A string that uniquely identifies the source in the style to which it is added.
`source`	The source from which to obtain the data to style. If the source has not yet been added to the current style, the behavior is undefined.

Return Value

An initialized foreground style layer.

View Source on GitHub

Accessing the Paint Attributes

circleBlur
Amount to blur the circle. 1 blurs the circle such that only the centerpoint is full opacity.

The default value of this property is an MGLStyleValue object containing an NSNumber object containing the float 0. Set this property to nil to reset it to the default value.

You can set this property to an instance of:
- MGLConstantStyleValue
- MGLCameraStyleFunction with an interpolation mode of:
  
  MGLInterpolationModeExponential
  
  MGLInterpolationModeInterval
- MGLSourceStyleFunction with an interpolation mode of:
  
  MGLInterpolationModeExponential
  
  MGLInterpolationModeInterval
  
  MGLInterpolationModeCategorical
  
  MGLInterpolationModeIdentity
- MGLCompositeStyleFunction with an interpolation mode of:
  
  MGLInterpolationModeExponential
  
  MGLInterpolationModeInterval
  
  MGLInterpolationModeCategorical
Declaration
Objective-C

@property (assign, readwrite, nonatomic, null_resettable) MGLStyleValue<NSNumber *> *circleBlur;
Swift

var circleBlur: MGLStyleValue
View Source on GitHub
circleBlurTransition
The transition affecting any changes to this layer’s circleBlur property.

This property corresponds to the circle-blur-transition property in the style JSON file format.
Declaration
Objective-C

@property (assign, readwrite, nonatomic) MGLTransition circleBlurTransition;
Swift

var circleBlurTransition: MGLTransition { get set }
View Source on GitHub
circleColor
The fill color of the circle.

The default value of this property is an MGLStyleValue object containing NSColor.blackColor. Set this property to nil to reset it to the default value.

You can set this property to an instance of:
- MGLConstantStyleValue
- MGLCameraStyleFunction with an interpolation mode of:
  
  MGLInterpolationModeExponential
  
  MGLInterpolationModeInterval
- MGLSourceStyleFunction with an interpolation mode of:
  
  MGLInterpolationModeExponential
  
  MGLInterpolationModeInterval
  
  MGLInterpolationModeCategorical
  
  MGLInterpolationModeIdentity
- MGLCompositeStyleFunction with an interpolation mode of:
  
  MGLInterpolationModeExponential
  
  MGLInterpolationModeInterval
  
  MGLInterpolationModeCategorical
Declaration
Objective-C

@property (assign, readwrite, nonatomic, null_resettable) MGLStyleValue<NSColor *> *circleColor;
Swift

var circleColor: MGLStyleValue
View Source on GitHub
circleColorTransition
The transition affecting any changes to this layer’s circleColor property.

This property corresponds to the circle-color-transition property in the style JSON file format.
Declaration
Objective-C

@property (assign, readwrite, nonatomic) MGLTransition circleColorTransition;
Swift

var circleColorTransition: MGLTransition { get set }
View Source on GitHub
circleOpacity
The opacity at which the circle will be drawn.

The default value of this property is an MGLStyleValue object containing an NSNumber object containing the float 1. Set this property to nil to reset it to the default value.

You can set this property to an instance of:
- MGLConstantStyleValue
- MGLCameraStyleFunction with an interpolation mode of:
  
  MGLInterpolationModeExponential
  
  MGLInterpolationModeInterval
- MGLSourceStyleFunction with an interpolation mode of:
  
  MGLInterpolationModeExponential
  
  MGLInterpolationModeInterval
  
  MGLInterpolationModeCategorical
  
  MGLInterpolationModeIdentity
- MGLCompositeStyleFunction with an interpolation mode of:
  
  MGLInterpolationModeExponential
  
  MGLInterpolationModeInterval
  
  MGLInterpolationModeCategorical
Declaration
Objective-C

@property (assign, readwrite, nonatomic, null_resettable) MGLStyleValue<NSNumber *> *circleOpacity;
Swift

var circleOpacity: MGLStyleValue
View Source on GitHub
circleOpacityTransition
The transition affecting any changes to this layer’s circleOpacity property.

This property corresponds to the circle-opacity-transition property in the style JSON file format.
Declaration
Objective-C

@property (assign, readwrite, nonatomic) MGLTransition circleOpacityTransition;
Swift

var circleOpacityTransition: MGLTransition { get set }
View Source on GitHub
circleRadius
Circle radius.

This property is measured in points.

The default value of this property is an MGLStyleValue object containing an NSNumber object containing the float 5. Set this property to nil to reset it to the default value.

You can set this property to an instance of:
- MGLConstantStyleValue
- MGLCameraStyleFunction with an interpolation mode of:
  
  MGLInterpolationModeExponential
  
  MGLInterpolationModeInterval
- MGLSourceStyleFunction with an interpolation mode of:
  
  MGLInterpolationModeExponential
  
  MGLInterpolationModeInterval
  
  MGLInterpolationModeCategorical
  
  MGLInterpolationModeIdentity
- MGLCompositeStyleFunction with an interpolation mode of:
  
  MGLInterpolationModeExponential
  
  MGLInterpolationModeInterval
  
  MGLInterpolationModeCategorical
Declaration
Objective-C

@property (assign, readwrite, nonatomic, null_resettable) MGLStyleValue<NSNumber *> *circleRadius;
Swift

var circleRadius: MGLStyleValue
View Source on GitHub
circleRadiusTransition
The transition affecting any changes to this layer’s circleRadius property.

This property corresponds to the circle-radius-transition property in the style JSON file format.
Declaration
Objective-C

@property (assign, readwrite, nonatomic) MGLTransition circleRadiusTransition;
Swift

var circleRadiusTransition: MGLTransition { get set }
View Source on GitHub
circleScaleAlignment
Controls the scaling behavior of the circle when the map is pitched.

The default value of this property is an MGLStyleValue object containing an NSValue object containing MGLCircleScaleAlignmentMap. Set this property to nil to reset it to the default value.

This attribute corresponds to the circle-pitch-scale layout property in the Mapbox Style Specification.

You can set this property to an instance of:
- MGLConstantStyleValue
- MGLCameraStyleFunction with an interpolation mode of MGLInterpolationModeInterval
Declaration
Objective-C

@property (assign, readwrite, nonatomic, null_resettable) MGLStyleValue<NSValue *> *circleScaleAlignment;
Swift

var circleScaleAlignment: MGLStyleValue
View Source on GitHub
circleStrokeColor
The stroke color of the circle.

The default value of this property is an MGLStyleValue object containing NSColor.blackColor. Set this property to nil to reset it to the default value.

You can set this property to an instance of:
- MGLConstantStyleValue
- MGLCameraStyleFunction with an interpolation mode of:
  
  MGLInterpolationModeExponential
  
  MGLInterpolationModeInterval
- MGLSourceStyleFunction with an interpolation mode of:
  
  MGLInterpolationModeExponential
  
  MGLInterpolationModeInterval
  
  MGLInterpolationModeCategorical
  
  MGLInterpolationModeIdentity
- MGLCompositeStyleFunction with an interpolation mode of:
  
  MGLInterpolationModeExponential
  
  MGLInterpolationModeInterval
  
  MGLInterpolationModeCategorical
Declaration
Objective-C

@property (assign, readwrite, nonatomic, null_resettable) MGLStyleValue<NSColor *> *circleStrokeColor;
Swift

var circleStrokeColor: MGLStyleValue
View Source on GitHub
circleStrokeColorTransition
The transition affecting any changes to this layer’s circleStrokeColor property.

This property corresponds to the circle-stroke-color-transition property in the style JSON file format.
Declaration
Objective-C

@property (assign, readwrite, nonatomic) MGLTransition circleStrokeColorTransition;
Swift

var circleStrokeColorTransition: MGLTransition { get set }
View Source on GitHub
circleStrokeOpacity
The opacity of the circle’s stroke.

The default value of this property is an MGLStyleValue object containing an NSNumber object containing the float 1. Set this property to nil to reset it to the default value.

You can set this property to an instance of:
- MGLConstantStyleValue
- MGLCameraStyleFunction with an interpolation mode of:
  
  MGLInterpolationModeExponential
  
  MGLInterpolationModeInterval
- MGLSourceStyleFunction with an interpolation mode of:
  
  MGLInterpolationModeExponential
  
  MGLInterpolationModeInterval
  
  MGLInterpolationModeCategorical
  
  MGLInterpolationModeIdentity
- MGLCompositeStyleFunction with an interpolation mode of:
  
  MGLInterpolationModeExponential
  
  MGLInterpolationModeInterval
  
  MGLInterpolationModeCategorical
Declaration
Objective-C

@property (assign, readwrite, nonatomic, null_resettable) MGLStyleValue<NSNumber *> *circleStrokeOpacity;
Swift

var circleStrokeOpacity: MGLStyleValue
View Source on GitHub
circleStrokeOpacityTransition
The transition affecting any changes to this layer’s circleStrokeOpacity property.

This property corresponds to the circle-stroke-opacity-transition property in the style JSON file format.
Declaration
Objective-C

@property (assign, readwrite, nonatomic) MGLTransition circleStrokeOpacityTransition;
Swift

var circleStrokeOpacityTransition: MGLTransition { get set }
View Source on GitHub
circleStrokeWidth
The width of the circle’s stroke. Strokes are placed outside of the circleRadius.

This property is measured in points.

The default value of this property is an MGLStyleValue object containing an NSNumber object containing the float 0. Set this property to nil to reset it to the default value.

You can set this property to an instance of:
- MGLConstantStyleValue
- MGLCameraStyleFunction with an interpolation mode of:
  
  MGLInterpolationModeExponential
  
  MGLInterpolationModeInterval
- MGLSourceStyleFunction with an interpolation mode of:
  
  MGLInterpolationModeExponential
  
  MGLInterpolationModeInterval
  
  MGLInterpolationModeCategorical
  
  MGLInterpolationModeIdentity
- MGLCompositeStyleFunction with an interpolation mode of:
  
  MGLInterpolationModeExponential
  
  MGLInterpolationModeInterval
  
  MGLInterpolationModeCategorical
Declaration
Objective-C

@property (assign, readwrite, nonatomic, null_resettable) MGLStyleValue<NSNumber *> *circleStrokeWidth;
Swift

var circleStrokeWidth: MGLStyleValue
View Source on GitHub
circleStrokeWidthTransition
The transition affecting any changes to this layer’s circleStrokeWidth property.

This property corresponds to the circle-stroke-width-transition property in the style JSON file format.
Declaration
Objective-C

@property (assign, readwrite, nonatomic) MGLTransition circleStrokeWidthTransition;
Swift

var circleStrokeWidthTransition: MGLTransition { get set }
View Source on GitHub
circleTranslation
The geometry’s offset.

This property is measured in points.

The default value of this property is an MGLStyleValue object containing an NSValue object containing a CGVector struct set to 0 points rightward and 0 points upward. Set this property to nil to reset it to the default value.

This attribute corresponds to the circle-translate layout property in the Mapbox Style Specification.

You can set this property to an instance of:
- MGLConstantStyleValue
- MGLCameraStyleFunction with an interpolation mode of:
  
  MGLInterpolationModeExponential
  
  MGLInterpolationModeInterval
Declaration
Objective-C

@property (assign, readwrite, nonatomic, null_resettable) MGLStyleValue<NSValue *> *circleTranslation;
Swift

var circleTranslation: MGLStyleValue
View Source on GitHub
circleTranslationTransition
The transition affecting any changes to this layer’s circleTranslation property.

This property corresponds to the circle-translate-transition property in the style JSON file format.
Declaration
Objective-C

@property (assign, readwrite, nonatomic) MGLTransition circleTranslationTransition;
Swift

var circleTranslationTransition: MGLTransition { get set }
View Source on GitHub
circleTranslationAnchor
Controls the translation reference point.

The default value of this property is an MGLStyleValue object containing an NSValue object containing MGLCircleTranslationAnchorMap. Set this property to nil to reset it to the default value.

This property is only applied to the style if circleTranslation is non-nil. Otherwise, it is ignored.

This attribute corresponds to the circle-translate-anchor layout property in the Mapbox Style Specification.

You can set this property to an instance of:
- MGLConstantStyleValue
- MGLCameraStyleFunction with an interpolation mode of MGLInterpolationModeInterval
Declaration
Objective-C

@property (assign, readwrite, nonatomic, null_resettable) MGLStyleValue<NSValue *> *circleTranslationAnchor;
Swift

var circleTranslationAnchor: MGLStyleValue
View Source on GitHub