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When World Partition is enabled, the world is divided into a grid and you can specify the lighting resolution for each grid cell. An actor with When a cell specifies an Enlighten Quality or Probe Resolution value, this applies to actors within the cell which have Enlighten Quality or Adaptive Probe Resolution set to Use Default uses the value from its containing grid cell. If its containing grid cell has no value, the actor falls back to the lighting resolution in the world properties.
To change the size of the grid cells, use Enlighten Resolution Cell Size in the world properties. All existing cell resolution values are cleared when the cell size is modified.
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