MGLStyleFunction
@interface MGLStyleFunction <T> : MGLStyleValue
An MGLStyleFunction
is a value function defining a style value that changes
as the zoom level changes. The layout and paint attribute properties of an
MGLStyleLayer
object can be set to MGLStyleFunction
objects. Use a zoom
level function to create the illusion of depth and control data density.
The MGLStyleFunction
class takes a generic parameter T
that indicates the
Foundation class being wrapped by this class.
-
Creates and returns an
MGLStyleFunction
object representing a linear zoom level function with any number of stops.Declaration
Objective-C
+ (nonnull instancetype)functionWithStops: (nonnull NSDictionary<NSNumber *, MGLStyleValue<T> *> *)stops;
Swift
convenience init(stops: [NSNumber : MGLStyleValue
Parameters
stops
A dictionary associating zoom levels with style values.
Return Value
An
MGLStyleFunction
object with the given stops. -
Creates and returns an
MGLStyleFunction
object representing a zoom level function with an exponential base and any number of stops.Declaration
Objective-C
+ (nonnull instancetype) functionWithBase:(CGFloat)base stops:(nonnull NSDictionary<NSNumber *, MGLStyleValue<T> *> *)stops;
Swift
convenience init(base: CGFloat, stops: [NSNumber : MGLStyleValue
Parameters
base
The exponential base of the interpolation curve.
stops
A dictionary associating zoom levels with style values.
Return Value
An
MGLStyleFunction
object with the given base and stops.
-
Returns an
MGLStyleFunction
object representing a zoom level function with an exponential base and any number of stops.Declaration
Objective-C
- (nonnull instancetype) initWithBase:(CGFloat)base stops:(nonnull NSDictionary<NSNumber *, MGLStyleValue<T> *> *)stops;
Swift
init(base: CGFloat, stops: [NSNumber : MGLStyleValue
Parameters
base
The exponential base of the interpolation curve.
stops
A dictionary associating zoom levels with style values.
Return Value
An
MGLStyleFunction
object with the given base and stops.
-
The exponential base of the function’s interpolation curve.
The exponential base controls the rate at which the function’s output values increase. A value of 1 causes the function to increase linearly by zoom level. A higher exponential base causes the function’s output values to vary exponentially, increasing more rapidly towards the high end of the function’s range. The default value of this property is 1, for a linear curve.
Declaration
Objective-C
@property (assign, readwrite, nonatomic) CGFloat base;
Swift
var base: CGFloat { get set }
-
A dictionary associating zoom levels with style values.
Each of the function’s stops is represented by one key-value pair in the dictionary. Each key in the dictionary is an
NSNumber
object containing a floating-point zoom level. Each value in the dictionary is anMGLStyleValue
object containing the value of the style attribute when the map is at the associated zoom level. AnMGLStyleFunction
object may not be used recursively as a stop value.Declaration
Objective-C
@property (readwrite, copy, nonatomic) NSDictionary<NSNumber *, MGLStyleValue<T> *> *_Nonnull stops;
Swift
var stops: [NSNumber : MGLStyleValue