mapbox / mapbox/mapbox-maps-ios

Model Position Incorrectly Changed from Centre for some Coordinates

Open
#2,176 12 comments 0 reactions 0 assignees View on GitHub

Nobody has claimed this yet.

auto-triaged bug :beetle: needs info
Dominant language
Swift
Stars
601
Forks
196
PR merge metrics
No merged PRs in 30d

Description

## Environment

- Xcode version: 15.3
- iOS version: 17.4
- Devices affected:
- Maps SDK Version: 11.1.0

## Observed behavior and steps to reproduce

I encountered an issue where the position of a model in my Mapbox implementation is being inaccurately adjusted for certain coordinates but camera position is fine. The model, which should be centered at specified coordinates, is shifting its position unexpectedly. This behavior occurs despite correct implementation of adding the model, setting camera parameters.

**Code for adding model**

```

let plane = Bundle.main.url(
forResource: "A320",
withExtension: "glb")!.absoluteString
var source = GeoJSONSource(id: "source-id")
source.maxzoom = 4
try? mapProxy?.map!.addStyleModel(modelId: "model-id-plane", modelUri: plane)
var planeFeature = Feature(geometry: Point(CLLocationCoordinate2D(latitude: 42.97330, longitude: -75.085930)))
planeFeature.properties = ["model-id-key": .string("model-id-plane")]
source.data = .featureCollection(FeatureCollection(features: [planeFeature]))
try? mapProxy?.map!.addSource(source)
var layer = ModelLayer(id: "model-layer-id", source: "source-id")
layer.modelId = .expression(Exp(.get) { "model-id-key" })
layer.modelType = .constant(.common3d)
layer.modelScale = .constant([1, 1, 1])
layer.modelTranslation = .constant([0, 0, 9753.60])
layer.modelRotation = .constant([0, 0, 186])
layer.maxZoom = 23
layer.minZoom = 5
layer.modelRotationTransition = StyleTransition(duration: 0.1, delay: 0.1)
layer.modelTranslationTransition = StyleTransition(duration: 0, delay: 0)
layer.modelCutoffFadeRange = .constant(0.0)
try? mapProxy?.map!.addLayer(layer)
```

**Code for setting camera:**

```

let freeCam = self.mapProxy?.map?.freeCameraOptions
freeCam?.altitude = 10253.6
freeCam?.location = CLLocationCoordinate2D(latitude: 42.97330, longitude: -75.085930)
freeCam?.setPitchBearingForPitch(0, bearing: 276)
mapProxy?.map?.freeCameraOptions = freeCam!
```

## Expected behavior

Model should appear at the centre like camera

**Pictures**

![plane](https://github.com/mapbox/mapbox-maps-ios/assets/82497041/9d175903-d4e8-4222-b85e-78d19ad833f3)

Contributor guide

Open the contributing guide

First steps

  1. Read the whole issue, then the project's contributing guide.
  2. Comment on the issue to say you are picking it up — it saves two people doing the same work.
  3. Fork the repository and make your change on a branch.
  4. Open a pull request that references the issue number.

Research direction

Start by reproducing the coordinate case using the provided model-layer and freeCameraOptions snippets in a minimal iOS Mapbox Maps SDK example. Compare the model's rendered position with the camera location and inspect model translation, rotation, and coordinate handling. Done means the model remains centered at the specified coordinates without breaking the reported camera behavior.

Written by the indexing model from the issue text.

Assessment

Tech stack
ios, swift
Domain
computer-graphics, mobile-dev
Issue type
Bug
Difficulty
4/5
Estimated time
3-5 days
Activity status
Stale
Clarity
Mostly clear
Newbie friendliness
35/100

Get new issues in your inbox

A short digest of beginner-friendly GitHub issues.