This section describes the effect of the Lighting Mode property of a Lighting Settings Asset.
The Lighting Mode determines the behavior of all Mixed Lights in all ScenesA Scene contains the environments and menus of your game. Think of each unique Scene file as a unique level. In each Scene, you place your environments, obstacles, and decorations, essentially designing and building your game in pieces. More info
See in Glossary that use the Lighting Settings Asset. The available modes are:
See render pipeline feature comparison for more information about support for each Lighting Mode across render pipelinesA series of operations that take the contents of a Scene, and displays them on a screen. Unity lets you choose from pre-built render pipelines, or write your own. More info
See in Glossary.
When you set a Scene’s Lighting Mode to Baked Indirect, Mixed Lights behave like Realtime LightsLight components whose Mode property is set to Realtime. Unity calculates and updates the lighting of Realtime Lights every frame at runtime. No Realtime Lights are precomputed. More info
See in Glossary, with the additional benefit of baking indirect lighting into lightmapsA pre-rendered texture that contains the effects of light sources on static objects in the scene. Lightmaps are overlaid on top of scene geometry to create the effect of lighting. More info
See in Glossary. GameObjects lit by Mixed Lights cast real-time shadows up to the Shadow Distance you define in the Project.
Mixed Lights behave as follows:
Because all shadows from Mixed Lights are real-time in Baked Indirect Lighting Mode, this can impact performance. You can reduce this impact by using the Shadow Distance property to limit the distance up to which Unity draws real-time shadows.
Similar to Baked Indirect Lighting Mode, Shadowmask Lighting Mode combines real-time direct lighting with baked indirect lighting. However, Shadowmask Lighting Mode differs from Baked Indirect Lighting Mode in the way that it renders shadows. Shadowmask Lighting Mode makes it possible for Unity to combine baked and real-time shadows at runtime and render shadows in the far distance. It does this by using an additional lightmap texture known as a shadow mask, and by storing additional information in Light ProbesLight probes store information about how light passes through space in your scene. A collection of light probes arranged within a given space can improve lighting on moving objects and static LOD scenery within that space. More info
See in Glossary. Unity generates Shadow masks and Light Probe occlusion data for baked shadows.
Shadowmask Lighting Mode provides the highest fidelity shadows among all the Lighting Modes, but has the highest performance cost and memory requirements. It’s suitable for rendering realistic scenes where distant GameObjects are visible, such as open worlds, on high-end or mid-range hardware.
Use the Quality Settings panel to set the Shadowmask Mode Unity uses at runtime.
When you set a Scene’s Lighting Mode to Shadowmask and your Project uses the Distance Shadowmask quality setting, Mixed Lights behave as follows.
When you set a Scene’s Lighting Mode to Shadowmask and your Project uses the Shadowmask quality setting, Mixed Lights behave as follows.
At runtime, Unity uses the shadow mask to determine whether a pixelThe smallest unit in a computer image. Pixel size depends on your screen resolution. Pixel lighting is calculated at every screen pixel. More info
See in Glossary is in shadow or not. The shadow mask Texture contains occlusion information about baked lightsLight components whose Mode property is set to Baked. Unity pre-calculates the illumination from Baked Lights before runtime, and does not include them in any runtime lighting calculations. More info
See in Glossary. It shares the same UV layout and resolution with its corresponding lightmap. It contains occlusion information for up to four lights per texel, stored in RGBA format.
If more than four lights overlap, any additional lights fall back to Baked Lighting. The baking system determines which lights fall back to Baked Lighting, and this stays consistent across bakes, unless you modify one of the overlapping lights. Light Probes also receive the same information for up to four lights.
Unity computes light overlapping independently of shadow receiving objects. So, an object can get the influence of ten different mixed lights all from the same Shadowmask/Probe channel, as long as those light bounding volumesA closed shape representing the edges and faces of a collider or trigger.
See in Glossary don’t overlap at any point in space. If some lights overlap then Unity uses more channels. And, if a light does overlap while all four channels are already in use, that light falls back to fully baked.
You can use the Shadow Distance property to limit the distance up to which Unity draws real-time shadows.
In Subtractive Lighting Mode, all Mixed Lights in your Scene provide baked direct and indirect lighting. Unity bakes shadows cast by static GameObjects into the lightmaps. In addition to the baked shadows, one Directional Light, known as the Main Directional Light, provides real-time shadows for dynamic GameObjects.
Because shadows are baked into the lightmaps, Unity doesn’t have the information it needs to accurately combine baked and real-time shadows at runtime. Instead, Unity provides a Realtime Shadow Color for reducing the contribution from the lightmap to create the illusion of a correct blend between baked and real-time shadows. You can also tweak the color to achieve a certain artistic style.
Subtractive Lighting Mode is useful on low-end hardware where performance is a concern, and where you need only one real-time shadow casting light. It doesn’t provide particularly realistic lighting effects, and is more suitable for stylized aesthetics, such as cel shading.
Unity automatically chooses the Directional Light in your Scene with the highest intensity value to be the Main Directional Light.
When you set a Scene’s Lighting Mode to Subtractive, Mixed Lights behave as follows.