getSwitchOverZoomFactors

Get the zoom factors where the device switches between physical lenses.

Usage

const camera = useRef<ZCamera>(null);
 
const factors = await camera.current?.getSwitchOverZoomFactors();
console.log('Lens switch points:', factors);
// e.g., [2.0, 6.0] on iPhone Pro

Returns

Promise<number[]> - Array of zoom factors where lens switches occur. Empty array for single-camera devices.

Lens Switching Behavior

Triple Camera (iPhone Pro)

Typically returns [2.0, 6.0]:

Below 2.0: Ultra-wide lens (0.5x-1x user-facing)
At 2.0: Switches FROM ultra-wide TO wide lens (1x user-facing)
2.0-6.0: Wide lens (1x-3x user-facing)
At 6.0: Switches FROM wide TO telephoto lens (3x user-facing)
Above 6.0: Telephoto lens (3x+ user-facing)

Dual Wide Camera (iPhone 11)

Typically returns [2.0]:

Below 2.0: Ultra-wide lens (0.5x-1x user-facing)
At 2.0: Switches FROM ultra-wide TO wide lens (1x user-facing)
Above 2.0: Wide lens with digital zoom (1x+ user-facing)

Dual Camera (iPhone X/XS)

Typically returns [2.0]:

Below 2.0: Wide lens with digital zoom (1x user-facing at 1.0)
At 2.0: Switches FROM wide TO telephoto lens (2x user-facing)
Above 2.0: Telephoto lens with digital zoom (2x+ user-facing)

Single Camera (iPhone SE, Air)

Returns [] - No lens switching, all zoom is digital.

Example

Smooth Zoom UI with Lens Indicators

import { useEffect, useRef, useState } from 'react';
import { View, Text, Slider } from 'react-native';
import { ZCamera } from '@succinctlabs/react-native-zcam1';
 
function CameraWithZoomIndicators({ captureInfo }) {
  const camera = useRef<ZCamera>(null);
  const [zoom, setZoom] = useState(2.0);
  const [minZoom, setMinZoom] = useState(1.0);
  const [maxZoom, setMaxZoom] = useState(15.0);
  const [switchPoints, setSwitchPoints] = useState<number[]>([]);
 
  useEffect(() => {
    (async () => {
      if (!camera.current) return;
      
      const min = await camera.current.getMinZoom();
      const max = await camera.current.getMaxZoom();
      const factors = await camera.current.getSwitchOverZoomFactors();
      
      setMinZoom(min);
      setMaxZoom(max);
      setSwitchPoints(factors);
    })();
  }, []);
 
  const getCurrentLens = () => {
    if (switchPoints.length === 0) return 'Single';
    if (switchPoints.length === 2) {
      // Triple camera
      if (zoom < switchPoints[0]) return '0.5x Ultra-Wide';
      if (zoom < switchPoints[1]) return '1x Wide';
      return '3x Telephoto';
    }
    // Dual camera
    if (zoom < switchPoints[0]) return 'Wide';
    return 'Telephoto';
  };
 
  const handleZoomChange = (value: number) => {
    setZoom(value);
    camera.current?.setZoomAnimated(value);
  };
 
  return (
    <View style={{ flex: 1 }}>
      <ZCamera
        ref={camera}
        captureInfo={captureInfo}
        zoom={zoom}
        style={{ flex: 1 }}
      />
      <View style={{ padding: 16 }}>
        <Text>Current Lens: {getCurrentLens()}</Text>
        <Text>Zoom: {(zoom / 2).toFixed(1)}x (device: {zoom.toFixed(1)})</Text>
        <Slider
          value={zoom}
          minimumValue={minZoom}
          maximumValue={maxZoom}
          onValueChange={handleZoomChange}
        />
      </View>
    </View>
  );
}

Snap to Lens Switching Points

import { useRef, useState } from 'react';
import { Button, View } from 'react-native';
import { ZCamera } from '@succinctlabs/react-native-zcam1';
 
function CameraWithLensButtons({ captureInfo }) {
  const camera = useRef<ZCamera>(null);
  const [switchPoints, setSwitchPoints] = useState<number[]>([]);
 
  useEffect(() => {
    camera.current?.getSwitchOverZoomFactors().then(setSwitchPoints);
  }, []);
 
  const setLens = (factor: number) => {
    camera.current?.setZoomAnimated(factor);
  };
 
  return (
    <View style={{ flex: 1 }}>
      <ZCamera ref={camera} captureInfo={captureInfo} style={{ flex: 1 }} />
      <View style={{ flexDirection: 'row', padding: 16 }}>
        {switchPoints.length >= 1 && (
          <>
            <Button title="0.5x" onPress={() => setLens(1.0)} />
            <Button title="1x" onPress={() => setLens(2.0)} />
          </>
        )}
        {switchPoints.length >= 2 && (
          <Button title="3x" onPress={() => setLens(6.0)} />
        )}
      </View>
    </View>
  );
}

Notes

Returns empty array on single-camera devices
Factors are in device zoom coordinates (where 2.0 typically = 1x user-facing)
Use with hasUltraWideCamera() to interpret zoom factors correctly
Combine with getMinZoom() and getMaxZoom() for full zoom range
Use setZoomAnimated() for smooth transitions across lens boundaries