The Environment Light Mixer is an editor window where you can create and edit a Level's environment lighting components for sky, clouds, atmosphere lights, sky lighting, and height fog. For designers and artists, it's a single window that enables you to edit these components quickly and choose the level of property detail you want access to.
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Opening the Environment Light Mixer
Open the Environment Light Mixer from the Main Menu by selecting Window > Env. Light Mixer.
Environment Light Mixer Interface
The Environment Light Mixer's interface is comprised of two primary elements:
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Toolbar
The Toolbar is where you'll add components and set the level of property detail that is visible in the Components Panels. Enable Only show atmospheric lights to list only a Directional Light that has Atmosphere Sun Light enabled.
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Adding Scene Components
When you open the Environment Light Mixer window, if you are starting from an empty Level, you will find the following components listed:
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If any of these components is added from the Place Actors panel or already exists in the scene, the list will automatically reflect what is not currently added. Likewise, when you remove a component from the scene, the create button becomes available again in the toolbar.
The toolbar also has a Create Height Fog button, which adds an Exponential Height Fog and works the same way.
Controlling the Amount of Properties Detail
When one of the available components is referenced in your Level – whether you added it through the Environment Light Mixer, or it already exists – the component's properties are added to the Components Panel where you can adjust and edit various properties for each of them.
For those that want maximum control over editing of their components, you can change the amount of properties shown using the details dropdown in the toolbar:
Minimal provides the bare essentials for components.
Normal provides the common properties for components.
Normal+Advanced provides common and advanced properties for components.
Below are examples of the amount of properties shown for the Directional Light using each detail amount:
 |  |  |
Minimal | Normal | Normal+Advanced |
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Components Panels
The Components Panels lists any of the components available in the Toolbar to add to your scene. It includes components for Sky Atmosphere, Volumetric Clouds, a Directional Light, a Sky Light, and Exponential Height Fog.
By default, the properties displayed for each component are limited to their Minimal set but can be extended to show more using the details dropdown in the toolbar.
