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# MDLProbePlacement.irradianceDistribution

An option to examine the lighting conditions at various positions in the scene being evaluated, then place light probes only at the locations where each contributes optimally to scene lighting.

```
case irradianceDistribution
```

## Discussion

If you use this heuristic, your data source must implement the [`sphericalHarmonicsCoefficients(atPosition:)`](/documentation/ModelIO/MDLLightProbeIrradianceDataSource/sphericalHarmonicsCoefficients(atPosition:)) method.

---

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