Lighting Layers

Definition

A lighting layer is a grouping of light information that contains multiple lights.

The lighting that is visible on a model is the result of an analysis of the stack of lighting layers. Each surface is lit based on the first visible layer in which an lighting is assigned to the surface.

Lighting layers can be used just like other layers, as targets of configuration rules. This allows, for example, indicator lights, LEDs and other lights to be turned on or off when a configuration symbol is enabled in the configuration browser, or according to the position of configuration keys in an animation timeline.

In the Illumination  tab in the Shaper sidebar, the Illumination Layer zone provides the tools to create, adjust, and delete layers.

Operations on Lighting Layers

The main buttons are available below the list of layers:

Icon	Description
	New lighting layer.
	Duplicate lighting layer.
	Add new lighting color to the layer.
	Rename lighting layer.
	Import lighting layer.
	Export lighting layer.
	Delete lighting layer.

The buttons to rename, duplicate, export or delete a layer affect only the selected layer. When multiple layers are selected, these buttons only affect the leader of the selection. The leader layer has a dotted border and is highlighted in light gray.

Each lighting layer has its own set of active values for modulation color, intensity, visibility, and configuration use. The active set of color values is marked with a check in the visibility column in the Layers list. When more than one layer is visible, the active values for each layer are combined.

The columns to the right of the name of the layer display the value of each of these properties. To change the value, click on its representation in the corresponding column.

Property	Description
Modulation color	The color of the lightmap is multiplied by the color of the layer. This color is always white by default. Click on the colored rectangle to open the color chooser and modify the color.
Intensity	The intensity of the lighting can be modified. You can set it to 0 or to any positive decimal value. By default, the intensity is set to 1, which represents a normal lighting.
Visibility	Illumination layers can be visible or hidden. During the analysis of the stack of layers, hidden layers are skipped. New layers are visible by default. Lights in a visible layer are shown in blue in the viewport. Lights in an invisible layer produce no effect and are displayed in red in the viewport.
Configuration	If the layer is used as a target of a configuration rule, the icon is displayed. Clicking on this icon will select the corresponding rule in the Configuration Editor.

You can also right-click on a lighting layer in order to copy its lightmaps to another layer in the list.

Using Lighting Layers

Illumination layers can require significant computing power. To limit this, lighting layers have been optimized for certain uses.

Substitution

Use a lighting layer when you have multiple geometric versions of your model. For example, you might be working on a seat that can be marketed with or without a headrest. Without a lighting layer, you must calculate the lightmap for the whole model. When you view the version with no headrest, however, the zone where the headrest would have been remains black: no lightmap was calculated for this zone.

To correct this, use a lighting layer.

Configuration

Use a lighting layer when your light sources need to be animated or configurable.

Put only the lights that must be turned on or off together in a separate layer.

The activation of layers is configurable. As with other types of layers, lighting layers can be dropped onto the Configurations editor.

The set of color and intensity values of each layer is also configurable. The lighting color set can also be dropped onto the Configurations editor.

Recommendations

To improve performance, follow these recommendations:

• Put all related lights in the same layer.
• Make sure that it isn't possible to have multiple layers containing sky lights active at the same time.
• Use the minimum number of layers that you can.
• Avoid using multiple sky lights to create the effect of an exterior environment. This effect can be created in Matter with a lighting environment and a real-time sun.

Settings for a Lighting Layer

Select a lighting layer by clicking on it. The light sources in this layer are now shown in white in the viewport. They are also listed below in the Light Settings zone.

In addition to the lights contained in the layer, layers also contain additional settings that determine the aspect of their illumination. These settings are found in the Lighting Settings zone. They apply to all lights in the layer.

• Exposure
• Contrast
• Lightmap format:
  • Color: To obtain shadow rendering that takes the lighting colors into account, choose the Color format.
  • Luminance : Use the Luminance format to obtain a relatively rapid rendering.
  • Luminance HQ
  • Luminance HDR: The Luminance HDR lightmap texture format is designed for the shadow rendering of HDR images and manages light sources significantly more intense than the Luminance and Luminance HQ formats.
• The lightmap settings:
  • The resolution of the textures to be produced,
  • The size of the shadowmaps,
  • The choice to render the unlit surfaces using Environment-type lighting.