MGLFillExtrusionStyleLayer

@interface MGLFillExtrusionStyleLayer : MGLVectorStyleLayer

An MGLFillExtrusionStyleLayer is a style layer that renders one or more 3D extruded polygons on the map.

Use a fill-extrusion style layer to configure the visual appearance of polygon or multipolygon features. These features can come from vector tiles loaded by an MGLVectorTileSource object, or they can be MGLPolygon, MGLPolygonFeature, MGLMultiPolygon, or MGLMultiPolygonFeature instances in an MGLShapeSource or MGLComputedShapeSource object.

You can access an existing fill-extrusion 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 fill-extrusion style layer and add it to the style using a method such as -[MGLStyle addLayer:].

Example

let layer = MGLFillExtrusionStyleLayer(identifier: "buildings", source: buildings)
layer.sourceLayerIdentifier = "building"
layer.fillExtrusionHeight = NSExpression(forKeyPath: "height")
layer.fillExtrusionBase = NSExpression(forKeyPath: "min_height")
layer.predicate = NSPredicate(format: "extrude == 'true'")
mapView.style?.addLayer(layer)

-initWithIdentifier:source:

Returns a fill-extrusion 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.

Accessing the Paint Attributes

fillExtrusionBase

The height with which to extrude the base of this layer. Must be less than or equal to fillExtrusionHeight.

This property is measured in meters.

The default value of this property is an expression that evaluates to the float 0. Set this property to nil to reset it to the default value.

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

You can set this property to an expression containing any of the following:

• Constant numeric values no less than 0
• Predefined functions, including mathematical and string operators
• Conditional expressions
• Variable assignments and references to assigned variables
• Interpolation and step functions applied to the $zoomLevel variable and/or feature attributes

Declaration

Objective-C

@property (nonatomic, assign, unsafe_unretained, readwrite, null_resettable)
NSExpression *fillExtrusionBase;

Swift

var fillExtrusionBase: NSExpression! { get set }

fillExtrusionBaseTransition

The transition affecting any changes to this layer’s fillExtrusionBase property.

This property corresponds to the fill-extrusion-base-transition property in the style JSON file format.

Declaration

Objective-C

@property (nonatomic, assign, unsafe_unretained, readwrite)
MGLTransition fillExtrusionBaseTransition;

Swift

var fillExtrusionBaseTransition: MGLTransition { get set }

fillExtrusionColor

The base color of this layer. The extrusion’s surfaces will be shaded differently based on this color in combination with the light settings. If this color is specified with an alpha component, the alpha component will be ignored; use fillExtrusionOpacity to set layer opacityco.

The default value of this property is an expression that evaluates to UIColor.blackColor. Set this property to nil to reset it to the default value.

This property is only applied to the style if fillExtrusionPattern is set to nil. Otherwise, it is ignored.

You can set this property to an expression containing any of the following:

• Constant UIColor values
• Predefined functions, including mathematical and string operators
• Conditional expressions
• Variable assignments and references to assigned variables
• Interpolation and step functions applied to the $zoomLevel variable and/or feature attributes

Declaration

Objective-C

@property (nonatomic, assign, unsafe_unretained, readwrite, null_resettable)
NSExpression *fillExtrusionColor;

Swift

var fillExtrusionColor: NSExpression! { get set }

fillExtrusionColorTransition

The transition affecting any changes to this layer’s fillExtrusionColor property.

This property corresponds to the fill-extrusion-color-transition property in the style JSON file format.

Declaration

Objective-C

@property (nonatomic, assign, unsafe_unretained, readwrite)
MGLTransition fillExtrusionColorTransition;

Swift

var fillExtrusionColorTransition: MGLTransition { get set }

fillExtrusionHasVerticalGradient

Whether to apply a vertical gradient to the sides of a fill-extrusion layer. If true, sides will be shaded slightly darker farther down.

The default value of this property is an expression that evaluates to YES. Set this property to nil to reset it to the default value.

This attribute corresponds to the fill-extrusion-vertical-gradient layout property in the GL Style Specification.

You can set this property to an expression containing any of the following:

• Constant Boolean values
• Predefined functions, including mathematical and string operators
• Conditional expressions
• Variable assignments and references to assigned variables
• Step functions applied to the $zoomLevel variable

This property does not support applying interpolation functions to the $zoomLevel variable or applying interpolation or step functions to feature attributes.

Declaration

Objective-C

@property (nonatomic, assign, unsafe_unretained, readwrite, null_resettable)
NSExpression *fillExtrusionHasVerticalGradient;

Swift

var fillExtrusionHasVerticalGradient: NSExpression! { get set }

fillExtrusionHeight

The height with which to extrude this layer.

This property is measured in meters.

The default value of this property is an expression that evaluates to the float 0. Set this property to nil to reset it to the default value.

You can set this property to an expression containing any of the following:

• Constant numeric values no less than 0
• Predefined functions, including mathematical and string operators
• Conditional expressions
• Variable assignments and references to assigned variables
• Interpolation and step functions applied to the $zoomLevel variable and/or feature attributes

Declaration

Objective-C

@property (nonatomic, assign, unsafe_unretained, readwrite, null_resettable)
NSExpression *fillExtrusionHeight;

Swift

var fillExtrusionHeight: NSExpression! { get set }

fillExtrusionHeightTransition

The transition affecting any changes to this layer’s fillExtrusionHeight property.

This property corresponds to the fill-extrusion-height-transition property in the style JSON file format.

Declaration

Objective-C

@property (nonatomic, assign, unsafe_unretained, readwrite)
MGLTransition fillExtrusionHeightTransition;

Swift

var fillExtrusionHeightTransition: MGLTransition { get set }

fillExtrusionOpacity

The opacity of the entire fill extrusion layer. This is rendered on a per-layer, not per-feature, basis, and data-driven styling is not available.

The default value of this property is an expression that evaluates to the float 1. Set this property to nil to reset it to the default value.

You can set this property to an expression containing any of the following:

• Constant numeric values between 0 and 1 inclusive
• Predefined functions, including mathematical and string operators
• Conditional expressions
• Variable assignments and references to assigned variables
• Interpolation and step functions applied to the $zoomLevel variable

This property does not support applying interpolation or step functions to feature attributes.

Declaration

Objective-C

@property (nonatomic, assign, unsafe_unretained, readwrite, null_resettable)
NSExpression *fillExtrusionOpacity;

Swift

var fillExtrusionOpacity: NSExpression! { get set }

fillExtrusionOpacityTransition

The transition affecting any changes to this layer’s fillExtrusionOpacity property.

This property corresponds to the fill-extrusion-opacity-transition property in the style JSON file format.

Declaration

Objective-C

@property (nonatomic, assign, unsafe_unretained, readwrite)
MGLTransition fillExtrusionOpacityTransition;

Swift

var fillExtrusionOpacityTransition: MGLTransition { get set }

fillExtrusionPattern

Name of image in style images to use for drawing image fill-extrusions. For seamless patterns, image width and height must be a factor of two (2, 4, 8, …, 512).

You can set this property to an expression containing any of the following:

• Constant string values
• Predefined functions, including mathematical and string operators
• Conditional expressions
• Variable assignments and references to assigned variables
• Interpolation and step functions applied to the $zoomLevel variable and/or feature attributes

Declaration

Objective-C

@property (nonatomic, assign, unsafe_unretained, readwrite, null_resettable)
NSExpression *fillExtrusionPattern;

Swift

var fillExtrusionPattern: NSExpression! { get set }

fillExtrusionPatternTransition

The transition affecting any changes to this layer’s fillExtrusionPattern property.

This property corresponds to the fill-extrusion-pattern-transition property in the style JSON file format.

Declaration

Objective-C

@property (nonatomic, assign, unsafe_unretained, readwrite)
MGLTransition fillExtrusionPatternTransition;

Swift

var fillExtrusionPatternTransition: MGLTransition { get set }

fillExtrusionTranslation

The geometry’s offset.

This property is measured in points.

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

This attribute corresponds to the fill-extrusion-translate layout property in the GL Style Specification.

You can set this property to an expression containing any of the following:

• Constant CGVector values
• Predefined functions, including mathematical and string operators
• Conditional expressions
• Variable assignments and references to assigned variables
• Interpolation and step functions applied to the $zoomLevel variable

This property does not support applying interpolation or step functions to feature attributes.

Declaration

Objective-C

@property (nonatomic, assign, unsafe_unretained, readwrite, null_resettable)
NSExpression *fillExtrusionTranslation;

Swift

var fillExtrusionTranslation: NSExpression! { get set }

fillExtrusionTranslationTransition

The transition affecting any changes to this layer’s fillExtrusionTranslation property.

This property corresponds to the fill-extrusion-translate-transition property in the style JSON file format.

Declaration

Objective-C

@property (nonatomic, assign, unsafe_unretained, readwrite)
MGLTransition fillExtrusionTranslationTransition;

Swift

var fillExtrusionTranslationTransition: MGLTransition { get set }

fillExtrusionTranslationAnchor

Controls the frame of reference for fillExtrusionTranslation.

The default value of this property is an expression that evaluates to map. Set this property to nil to reset it to the default value.

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

This attribute corresponds to the fill-extrusion-translate-anchor layout property in the GL Style Specification.

You can set this property to an expression containing any of the following:

• Constant MGLFillExtrusionTranslationAnchor values
• Any of the following constant string values:
• map: The fill extrusion is translated relative to the map.
• viewport: The fill extrusion is translated relative to the viewport.
• Predefined functions, including mathematical and string operators
• Conditional expressions
• Variable assignments and references to assigned variables
• Step functions applied to the $zoomLevel variable

This property does not support applying interpolation functions to the $zoomLevel variable or applying interpolation or step functions to feature attributes.

Declaration

Objective-C

@property (nonatomic, assign, unsafe_unretained, readwrite, null_resettable)
NSExpression *fillExtrusionTranslationAnchor;

Swift

var fillExtrusionTranslationAnchor: NSExpression! { get set }