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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 Enlighten Quality or Adaptive Probe Resolution set to Use Default uses the value from its containing grid cell.
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.
With an actor selected, use the Set Cell Quality or Set Cell Probe Resolution menus to assign a lighting resolution for the cell that contains the selected actor.
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