Instead of lighting the small objects with lightmaps, we'll use probe lighting. This is more efficient for small objects that would use lots of charts if they used lightmaps.

From the View Mode menu, select Unlit to show the level with the default editor visualizations.
In the World Outliner, double-click the actor Props_Rubbish_Bag19 to focus on it.

Like everything else in the level right now, the actor is lit by a lightmap. We can see this under Details > Enlighten > Lighting Mode.

Like the lamppost in the previous page, this actor is making inefficient use of lightmaps. Let's change that.
Hold Ctrl to select multiple actors and select the nearby Props_Rubbish_Box39 and Props_Rubbish_Box43 actors:
In the Details panel, under Enlighten > Set Asset Lighting Mode, select Probe to change the lighting mode for actors that use these meshes.

The Set Asset Lighting Mode property controls the lighting mode of the static mesh asset used by the actor. It affects all the actors that use the asset.
Under View Mode > Enlighten, choose Lighting Mode.

This shows the lighting mode used by the actors in the level. Actors that use lightmaps are orange. Actors that use probe lighting are green.
Before changing the lighting mode After
The actors are orange, indicating that they use lightmaps. The actors are green, indicating that they use probes.
The following actors use small static mesh assets that would be best lit using Probe lighting:
- Props_AirCon01
- Props_Balcony_01
- Props_BalconyStairs_01
- Props_ChainFence01
- Props_LampPost01
- Props_Pipes_Corner01
- Props_Pipes_Long01
- Props_SatDish2
- Props_VentUnit01
- Signs_Hanging_Cable01
- Signs_Hanging_CablesMulti
- Signs_Horizontal_HangBroken
- Signs_Horizontal_HangLarge
Using Details > Enlighten > Set Asset Lighting Mode, set the Probe lighting mode for all the static mesh assets used by these actors.
Before changing asset lighting mode After
Actors using the Probe lighting mode are excluded from Enlighten computations, so they don't emit light onto other actors. We want the illuminated signs in our level to emit light, so we'll continue to use lightmaps to light these signs.

The lighting could be more efficient if we use the Contribute Probe lighting mode, but we'll cover that option in another tutorial.
From the View Mode menu, select Unlit to show the level with the default editor visualizations.

Next

5. Use shared lightmaps