Rysuj linie łamane na mapie

import GoogleMaps import UIKit  final class PolylinesViewController: UIViewController {   private lazy var styles: [GMSStrokeStyle] = {     let greenStyle = GMSStrokeStyle.gradient(from: .green, to: UIColor.green.withAlphaComponent(0))     let redStyle = GMSStrokeStyle.gradient(from: UIColor.red.withAlphaComponent(0), to: .red)     return [greenStyle, redStyle, GMSStrokeStyle.solidColor(UIColor(white: 0, alpha: 0))]   }()   private var pathLength: Double = 0   private var pos: Double = 0   private var polylines: [GMSPolyline] = []    private lazy var mapView: GMSMapView = {     let camera = GMSCameraPosition(latitude: -30, longitude: -175, zoom: 3)     return GMSMapView(frame: .zero, camera: camera)   }()    override func loadView() {     view = mapView     mapView.accessibilityElementsHidden = true   }    override func viewDidLoad() {     super.viewDidLoad()      var path = GMSMutablePath()     path.addLatitude(-33.866901, longitude: 151.195988)     path.addLatitude(-18, longitude: 179)     path.addLatitude(21.291982, longitude: -157.821856)     path.addLatitude(37.423802, longitude: -122.091859)     path.addLatitude(-12, longitude: -77)     path.addLatitude(-33.866901, longitude: 151.195988)     path = path.pathOffset(byLatitude: -30, longitude: 0)     pathLength = path.length(of: .geodesic) / 21     for i in 0..<30 {       let polyline = GMSPolyline(path: path.pathOffset(byLatitude: Double(i) * 1.5, longitude: 0))       polyline.strokeWidth = 8       polyline.geodesic = true       polyline.map = mapView       polylines.append(polyline)     }     animatePath()   }    // Updates the path style every 0.1 seconds.   private func animatePath() {     polylines.forEach {       if let path = $0.path {         $0.spans = GMSStyleSpansOffset(path, styles, [NSNumber(value: pathLength)], .geodesic, pos)       }     }     pos -= 50000      DispatchQueue.main.asyncAfter(deadline: DispatchTime.now() + 0.1) {       self.animatePath()     }   } }
PolylinesViewController.swift
       

#import "GoogleMapsDemos/Samples/PolylinesViewController.h"  #import <GoogleMaps/GoogleMaps.h>  static CLLocationCoordinate2D kSydneyAustralia = {-33.866901, 151.195988}; static CLLocationCoordinate2D kHawaiiUSA = {21.291982, -157.821856}; static CLLocationCoordinate2D kFiji = {-18, 179}; static CLLocationCoordinate2D kMountainViewUSA = {37.423802, -122.091859}; static CLLocationCoordinate2D kLimaPeru = {-12, -77}; static bool kAnimate = true;  @implementation PolylinesViewController {   NSArray *_styles;   NSArray *_lengths;   NSArray *_polys;   double _pos, _step;   GMSMapView *_mapView; }  - (void)tick {   for (GMSPolyline *poly in _polys) {     poly.spans = GMSStyleSpansOffset(poly.path, _styles, _lengths, kGMSLengthGeodesic, _pos);   }   _pos -= _step;   if (kAnimate) {     __weak id weakSelf = self;     dispatch_after(dispatch_time(DISPATCH_TIME_NOW, NSEC_PER_SEC / 10), dispatch_get_main_queue(),                    ^{                      [weakSelf tick];                    });   } }  - (void)initLines {   if (!_polys) {     NSMutableArray *polys = [NSMutableArray array];     GMSMutablePath *path = [GMSMutablePath path];     [path addCoordinate:kSydneyAustralia];     [path addCoordinate:kFiji];     [path addCoordinate:kHawaiiUSA];     [path addCoordinate:kMountainViewUSA];     [path addCoordinate:kLimaPeru];     [path addCoordinate:kSydneyAustralia];     path = [path pathOffsetByLatitude:-30 longitude:0];     _lengths = @[ @([path lengthOfKind:kGMSLengthGeodesic] / 21) ];     for (int i = 0; i < 30; ++i) {       GMSPolyline *poly = [[GMSPolyline alloc] init];       poly.path = [path pathOffsetByLatitude:(i * 1.5) longitude:0];       poly.strokeWidth = 8;       poly.geodesic = YES;       poly.map = _mapView;       [polys addObject:poly];     }     _polys = polys;   } }  - (void)viewDidLoad {   [super viewDidLoad];   GMSCameraPosition *camera = [GMSCameraPosition cameraWithLatitude:-30 longitude:-175 zoom:3];   GMSMapView *mapView = [GMSMapView mapWithFrame:CGRectZero camera:camera];   mapView.accessibilityElementsHidden = YES;   self.view = mapView;   _mapView = mapView;    CGFloat alpha = 1;   UIColor *green = [UIColor colorWithRed:0 green:1 blue:0 alpha:alpha];   UIColor *greenTransp = [UIColor colorWithRed:0 green:1 blue:0 alpha:0];   UIColor *red = [UIColor colorWithRed:1 green:0 blue:0 alpha:alpha];   UIColor *redTransp = [UIColor colorWithRed:1 green:0 blue:0 alpha:0];   GMSStrokeStyle *grad1 = [GMSStrokeStyle gradientFromColor:green toColor:greenTransp];   GMSStrokeStyle *grad2 = [GMSStrokeStyle gradientFromColor:redTransp toColor:red];   _styles = @[     grad1,     grad2,     [GMSStrokeStyle solidColor:[UIColor colorWithWhite:0 alpha:0]],   ];   _step = 50000;   [self initLines];   [self tick]; }  @end
PolylinesViewController.m