MGLLineStyleLayer

 
@interface MGLLineStyleLayer : MGLVectorStyleLayer

An MGLLineStyleLayer is a style layer that renders one or more stroked polylines on the map.

Use a line style layer to configure the visual appearance of polyline or multipolyline features in vector tiles loaded by an MGLVectorSource object or MGLPolyline, MGLPolylineFeature, MGLMultiPolyline, or MGLMultiPolylineFeature instances in an MGLShapeSource object.

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

Example

let layer = MGLLineStyleLayer(identifier: trails-path, source: trails)
layer.sourceLayerIdentifier = trails
layer.lineWidth = MGLStyleValue(interpolationBase: 1.5, stops: [
    14: MGLStyleValue(rawValue: 2),
    18: MGLStyleValue(rawValue: 20),
])
layer.lineColor = MGLStyleValue(rawValue: UIColor.brown)
layer.lineCap = MGLStyleValue(rawValue: NSValue(mglLineCap: .round))
layer.predicate = NSPredicate(format: %K == %@, trail-type, mountain-biking)
mapView.style.addLayer(layer)

Accessing the Layout Attributes

  • The display of line endings.

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

    Declaration

    Objective-C

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

    Swift

    var lineCap: MGLStyleValue
    View Source on GitHub

  • The display of lines when joining.

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

    Declaration

    Objective-C

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

    Swift

    var lineJoin: MGLStyleValue
    View Source on GitHub

  • Used to automatically convert miter joins to bevel joins for sharp angles.

    The default value of this property is an MGLStyleValue object containing an NSNumber object containing the float 2. Set this property to nil to reset it to the default value.

    This property is only applied to the style if lineJoin is set to an MGLStyleValue object containing an NSValue object containing MGLLineJoinMiter. Otherwise, it is ignored.

    Declaration

    Objective-C

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

    Swift

    var lineMiterLimit: MGLStyleValue
    View Source on GitHub

  • Used to automatically convert round joins to miter joins for shallow angles.

    The default value of this property is an MGLStyleValue object containing an NSNumber object containing the float 1.05. Set this property to nil to reset it to the default value.

    This property is only applied to the style if lineJoin is set to an MGLStyleValue object containing an NSValue object containing MGLLineJoinRound. Otherwise, it is ignored.

    Declaration

    Objective-C

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

    Swift

    var lineRoundLimit: MGLStyleValue
    View Source on GitHub

Accessing the Paint Attributes

  • Blur applied to the line, in points.

    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.

    Declaration

    Objective-C

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

    Swift

    var lineBlur: MGLStyleValue
    View Source on GitHub

  • The color with which the line will be drawn.

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

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

    Declaration

    Objective-C

    @property (assign, readwrite, nonatomic, null_resettable)
    MGLStyleValue<UIColor *> *lineColor;

    Swift

    var lineColor: MGLStyleValue
    View Source on GitHub

  • Specifies the lengths of the alternating dashes and gaps that form the dash pattern. The lengths are later scaled by the line width. To convert a dash length to points, multiply the length by the current line width.

    This property is measured in line widths.

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

    This attribute corresponds to the line-dasharray layout property in the Mapbox Style Specification.

    Declaration

    Objective-C

    @property (assign, readwrite, nonatomic, null_resettable)
    MGLStyleValue<NSArray<NSNumber *> *> *lineDashPattern;

    Swift

    var lineDashPattern: MGLStyleValue
    View Source on GitHub

  • Draws a line casing outside of a line’s actual path. Value indicates the width of the inner gap.

    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.

    Declaration

    Objective-C

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

    Swift

    var lineGapWidth: MGLStyleValue
    View Source on GitHub

  • The line’s offset. For linear features, a positive value offsets the line to the right, relative to the direction of the line, and a negative value to the left. For polygon features, a positive value results in an inset, and a negative value results in an outset.

    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.

    Declaration

    Objective-C

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

    Swift

    var lineOffset: MGLStyleValue
    View Source on GitHub

  • The opacity at which the line 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.

    Declaration

    Objective-C

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

    Swift

    var lineOpacity: MGLStyleValue
    View Source on GitHub

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

    Declaration

    Objective-C

    @property (assign, readwrite, nonatomic, null_resettable)
    MGLStyleValue<NSString *> *linePattern;

    Swift

    var linePattern: MGLStyleValue
    View Source on GitHub

  • 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 from the left and 0 points from the top. Set this property to nil to reset it to the default value.

    Declaration

    Objective-C

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

    Swift

    var lineTranslate: MGLStyleValue
    View Source on GitHub

  • Controls the translation reference point.

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

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

    Declaration

    Objective-C

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

    Swift

    var lineTranslateAnchor: MGLStyleValue
    View Source on GitHub

  • Stroke thickness.

    This property is measured in points.

    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.

    Declaration

    Objective-C

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

    Swift

    var lineWidth: MGLStyleValue
    View Source on GitHub