setting center coordinate changes zoom level after PR #1538 was merged

Describe the bug
Before #1538 was by @naftalibeder merged, setting the center coordinate only resulted in the camera panning to the new center without changing the zoom level.

After #1538 was merged, the camera zooms in to the center coordinate.

To Reproduce

I modified the bug report template. Click on “set center” to see the new behavior:

import React from 'react';
import {Button} from 'react-native';
import {
  MapView,
  ShapeSource,
  SymbolLayer,
  CircleLayer,
  Camera,
} from '@react-native-mapbox-gl/maps';
import bbox from '@turf/bbox';

const styles = {
  mapView: {flex: 1},
  circleLayer: {
    circleRadiusTransition: {duration: 5000},
    circleColor: '#ff0000',
  },
};

const features = {
  type: 'FeatureCollection',
  features: [
    {
      type: 'Feature',
      id: 'a-feature',
      properties: {
        icon: 'example',
        text: 'example-icon-and-label',
      },
      geometry: {
        type: 'Point',
        coordinates: [-74.00597, 40.71427],
      },
    },
    {
      type: 'Feature',
      id: 'b-feature',
      properties: {
        text: 'just-label',
      },
      geometry: {
        type: 'Point',
        coordinates: [-74.001097, 40.71527],
      },
    },
    {
      type: 'Feature',
      id: 'c-feature',
      properties: {
        icon: 'example',
      },
      geometry: {
        type: 'Point',
        coordinates: [-74.00697, 40.72427],
      },
    },
  ],
};

function getCameraBounds(geojsonObject) {
  const horizontalPadding = 100;
  const verticalPadding = 100;

  const mapBbox = bbox(geojsonObject);

  const cameraSettings = {
    bounds: {
      ne: [mapBbox[0], mapBbox[1]],
      sw: [mapBbox[2], mapBbox[3]],
      paddingBottom: horizontalPadding,
      paddingTop: horizontalPadding,
      paddingLeft: verticalPadding,
      paddingRight: verticalPadding,
    },

    padding: {
      paddingBottom: horizontalPadding,
      paddingTop: horizontalPadding,
      paddingLeft: verticalPadding,
      paddingRight: verticalPadding,
    }
    
  };
  return cameraSettings;
}

class BugReportExample extends React.Component {
  state = {
    radius: 20,
    centerCoordinate: undefined
  };

  render() {
    const cameraDefaultSettings = getCameraBounds(
      features,
    );
    const circleLayerStyle = {
      ...styles.circleLayer,
      ...{circleRadius: this.state.radius},
    };

    return (
      <>
        <Button
          title="Set Center"
          onPress={() => this.setState({centerCoordinate: [-74.00597, 40.71427]})}
        />
        <MapView style={styles.mapView}>
          <Camera defaultSettings={cameraDefaultSettings} centerCoordinate={this.state.centerCoordinate}  />
          <ShapeSource id={'shape-source-id-0'} shape={features}>
            <CircleLayer id={'circle-layer'} style={circleLayerStyle} />
            <SymbolLayer
              id="symbol-id"
              style={{
                iconImage: ['get', 'icon'],
              }}
            />
          </ShapeSource>
        </MapView>
      </>
    );
  }
}

export default BugReportExample;

Expected behavior
When setting the center coordinate of the camera, zoom level SHOULD NOT change.

Actual behavior
Setting the center coordinate of the camera causes zoom level to change.

Videos
The different behavior is shown in the following gifs:

[EDITED BY ferdicus to have a side by side comparison and save space]

BEFORE	AFTER
22df62cb is the commit right before #1538 was merged	6e7b0a4d is the commit of #1538

[naftalibeder]

@schiller-manuel @mfazekas @ferdicus I think this is all fair. Even without a new zoom specified, it makes sense to cache the previous zoom level and use that as an updated “default”.

@mfazekas To answer your question, in order to get padding to work with centerCoordinate, I needed to switch the SDK method used to center on the coordinate.

I think this is the conditional that @schiller-manuel is hitting without a zoom, meaning it falls back on the altitude returned from bounding around a single point - that’s why it zooms in so much in his example. That would be a bug, which is my fault.

Like I said before, my instinct would say to immediately fall back on the zoom default, but I would be fine looking for the previous cached zoom (if any) first, and then the default if there isn’t one.

I can work on this. I’ll also look into this. Sound okay?

[schiller-manuel]

@naftalibeder looks good to me, I tried your PR with my reproducer, the result is as expected: