MGLMapCamera doesn't respect edgePadding on SDK 5.6.0+

[maxmamis]

Flying to an MGLMapCamera does not respect insets as expected on SDK version 5.6.0+.

Minimal reproducible code:

let camera = mapView.cameraThatFitsCoordinateBounds(bound, edgePadding: UIEdgeInsets(top: 200, left: 0, bottom: 0, right: 0))
mapView.fly(to: camera, completionHandler: nil)

Expected behavior: zooms to the specified location in the bottom third of the screen. (This works properly on SDK version 5.5.0)
Observed behavior: zooms to the specified location dead center on the screen.

Tested using an iPhone XS running iOS 13.3.1

Screenshots:

5.7.0:

5.5.0:

[mfazekas]

I can confirm that there is an issue with asymmetric edgePadding.

In my testing 5.6.0 works fine too, while 5.7.0, 5.8.0 and 5.9.0.alpha1 is not.
Also users reported from android too. (https://github.com/react-native-mapbox-gl/maps/issues/841)

I've attached a ViewController that reproduces the issue.

In 5.7.0..5.9.0, i get this for pressing up and/or down:
edgePadding:UIEdgeInsets(top: 200.0, left: 0, bottom: 0.0, right: 0)) or edgePadding:UIEdgeInsets(top: 0.0, left: 0, bottom: 200.0, right: 0))

In 5.6.0 i get this for up: edgePadding:UIEdgeInsets(top: 200.0, left: 0, bottom: 0.0, right: 0))

and this for down :edgePadding:UIEdgeInsets(top:0.0, left: 0, bottom: 200.0, right: 0))

import UIKit
import Mapbox

class ViewController: UIViewController, MGLMapViewDelegate {
    var mapView : MGLMapView!
    
    override func viewDidLoad() {
        super.viewDidLoad()
        createUI()
    }
    
    func createUI() {
        let url = URL(string: "mapbox://styles/mapbox/streets-v11")
        mapView = MGLMapView(frame: view.bounds, styleURL: url)
        mapView.delegate = self
        mapView.setCenter(CLLocationCoordinate2D(latitude: 59.31, longitude: 18.06), zoomLevel: 9, animated: false)
        self.view.addSubview(mapView)
        mapView.translatesAutoresizingMaskIntoConstraints = false
        NSLayoutConstraint.activate([
            mapView.leftAnchor.constraint(equalTo: view.leftAnchor),
            mapView.rightAnchor.constraint(equalTo: view.rightAnchor),
            mapView.topAnchor.constraint(equalTo: view.topAnchor),
            mapView.bottomAnchor.constraint(equalTo: view.bottomAnchor)
        ])
        
        let button1 = UIButton()
        button1.setTitle("up", for: .normal)
        button1.setTitleColor(.systemBlue, for: .normal)
        button1.backgroundColor = .systemBackground
        button1.addTarget(self, action: #selector(up), for: .touchUpInside)

    
        let button2 = UIButton()
        button2.setTitle("down", for: .normal)
        button2.setTitleColor(.systemBlue, for: .normal)
        button2.backgroundColor = .systemBackground
        button2.addTarget(self, action: #selector(down), for: .touchUpInside)
        
        let buttons = UIStackView(arrangedSubviews: [button1, button2])
        buttons.translatesAutoresizingMaskIntoConstraints = false
        buttons.spacing = 32.0
        self.view.addSubview(buttons)
        NSLayoutConstraint.activate([
            buttons.bottomAnchor.constraint(equalTo: self.view.layoutMarginsGuide.bottomAnchor),
            buttons.centerXAnchor.constraint(equalTo: self.view.centerXAnchor)
        ])
    }
    
    func bounds() -> MGLCoordinateBounds {
        let diff = 0.1
        let center = CLLocationCoordinate2D(latitude: 59.31, longitude: 18.06)
        let sw = CLLocationCoordinate2D(latitude: center.latitude - diff, longitude: center.longitude - diff);
        let ne = CLLocationCoordinate2D(latitude: center.latitude + diff, longitude: center.longitude + diff);

        return MGLCoordinateBounds(sw: sw, ne: ne);
    }
    
    func drawBounds(_ style: MGLStyle) {
        let b = bounds()
        let coordinates = [
            b.sw,
            CLLocationCoordinate2D(latitude: b.sw.latitude, longitude: b.ne.longitude),
            b.ne,
            CLLocationCoordinate2D(latitude: b.ne.latitude, longitude: b.sw.longitude),
            b.sw
        ]

        let polyline = MGLPolyline(coordinates: coordinates, count: UInt(coordinates.count))
        let source = MGLShapeSource(identifier: "polyline", shape: polyline, options: nil)
        style.addSource(source)
        
        let layer = MGLLineStyleLayer(identifier: "polyline", source: source)
        layer.lineColor = NSExpression(forConstantValue: UIColor.red)
        layer.lineWidth = NSExpression(forConstantValue: 4.0)
        style.addLayer(layer)
    }

    @objc
    func up() {
        let camera = mapView.camera(mapView.camera.copy() as! MGLMapCamera,
            fitting: bounds(),
            edgePadding:UIEdgeInsets(top: 200.0, left: 0, bottom: 0.0, right: 0))
        mapView.fly(to: camera, withDuration: 1.0, completionHandler: nil)
    }
    
    @objc
    func down() {
        let camera = mapView.camera(
            mapView.camera.copy() as! MGLMapCamera,
            fitting: bounds(),
            edgePadding:UIEdgeInsets(top: 0.0, left: 0, bottom: 200.0, right: 0))
        mapView.fly(to: camera, withDuration: 1.0, completionHandler: nil)
    }
    
    func mapView(_ mapView: MGLMapView, didFinishLoading style: MGLStyle ) {
        drawBounds(style)
    }
}

[ferdicus]

any news on this issue?

[mfazekas]

I think the issue is that previously in the C++ mapbox-gl-native padding on CameraOptions was not used, but padding caused cameraCenter to adjust according to padding.

With the new C++ mapbox-gl-native CameraOptions padding field is now used. But when converting to/from MGLMapCamera it's lost.

The issue seems to be caused by this change:
https://github.com/mapbox/mapbox-gl-native/pull/16067/files

mapbox-gl-native-ios/platform/ios/src/MGLMapView.mm

Lines 4011 to 4025 in a139216

	- (MGLMapCamera *)cameraForCameraOptions:(const mbgl::CameraOptions &)cameraOptions
	{
	if (!_mbglMap)
	{
	return self.residualCamera;
	}
	mbgl::CameraOptions mapCamera = self.mbglMap.getCameraOptions();
	CLLocationCoordinate2D centerCoordinate = MGLLocationCoordinate2DFromLatLng(cameraOptions.center ? *cameraOptions.center : *mapCamera.center);
	double zoomLevel = cameraOptions.zoom ? *cameraOptions.zoom : self.zoomLevel;
	CLLocationDirection direction = cameraOptions.bearing ? mbgl::util::wrap(*cameraOptions.bearing, 0., 360.) : self.direction;
	CGFloat pitch = cameraOptions.pitch ? *cameraOptions.pitch : *mapCamera.pitch;
	CLLocationDistance altitude = MGLAltitudeForZoomLevel(zoomLevel, pitch, centerCoordinate.latitude, self.frame.size);
	return [MGLMapCamera cameraLookingAtCenterCoordinate:centerCoordinate altitude:altitude pitch:pitch heading:direction];
	}

https://github.com/mapbox/mapbox-gl-native-ios/blob/master/platform/darwin/src/MGLMapCamera.h

https://github.com/mapbox/mapbox-gl-native/blob/ae4a0c3ee3c9aadabb49f607425920ce38a53ec9/include/mbgl/map/camera.hpp#L29-L31

https://github.com/mapbox/mapbox-gl-native/blob/3600dd8a1a4d91290d752d699ed964eab03bb1a5/src/mbgl/map/map.cpp#L213-L230

[astojilj]

@mfazekas
Thanks for analysis. As a result of mapbox/mapbox-gl-native#16067, only specified padding is taken into account when calculating camera that fits geometry.

As you mentioned, the additive charter of inset management here:

mapbox-gl-native-ios/platform/ios/src/MGLMapView.mm

Lines 3979 to 3987 in a139216

	- (MGLMapCamera *)camera:(MGLMapCamera *)camera fittingShape:(MGLShape *)shape edgePadding:(UIEdgeInsets)insets {
	if (!_mbglMap)
	{
	return self.residualCamera;
	}
	mbgl::EdgeInsets padding = MGLEdgeInsetsFromNSEdgeInsets(insets);
	padding += MGLEdgeInsetsFromNSEdgeInsets(self.contentInset);

is lost when converting to/from MGLMapCamera it's lost.

Would this approach resolve the issue

https://github.com/mapbox/mapbox-navigation-ios/pull/2471/files#diff-a43bde32226ca771fb8f732e90f4fc6aR1297 ?

In short, mapView.contentInset is set to desired value (or use automatically set value) and .zero (edgePadding: .zero) used in camera fitting or cameraThatFitsShape.

cc @maxmamis @ferdicus

[pappalar]

I just wanted to understand if #323 should cover this issue.

I think this would also cover #86, as I had to resort to the camera inset since fly does not have a api to set the edge inset directly (while setCamera has)

- (void)flyToCamera:(MGLMapCamera *)camera withDuration:(NSTimeInterval)duration peakAltitude:(CLLocationDistance)peakAltitude completionHandler:(nullable void (^)(void))completion;

- (void)setCamera:(MGLMapCamera *)camera withDuration:(NSTimeInterval)duration animationTimingFunction:(nullable CAMediaTimingFunction *)function edgePadding:(UIEdgeInsets)edgePadding completionHandler:(nullable void (^)(void))completion;

[Bogdan-Belogurov]

Hi, I have the same issue.
Any news about #323?

Environment
Mapbox SDK version: v6.2.0
iOS versions: iOS 14 / 13
Xcode version: Xcode 12

[1ec5]

Some of the discussion in mapbox/mapbox-gl-native#15233 may also be relevant.

[maxmamis]

confirmed that #323 fixes the issue — would love to see it get merged!

[india2sarthak]

Any updates on this? Still an issue with 6.2.0