Shadowmask mode is a lighting mode shared by all Mixed Lights in a Scene. To set Mixed lighting to Shadowmask, open the Lighting window (menu: Window > RenderingThe process of drawing graphics to the screen (or to a render texture). By default, the main camera in Unity renders its view to the screen. More info
See in Glossary > Lighting Settings), click the Scene tab, navigate to Mixed LightingA Light Mode for creating indirect lighting, shadowmasks and subtractive lighting. Indirect lighting gets baked into lightmaps and light probes. Shadowmasks and light probes occlusion get generated for baked shadows. More info
See in Glossary and set the Lighting Mode to ShadowmaskA Texture that shares the same UV layout and resolution with its corresponding lightmap. More info
See in Glossary.
You also need to select the desired Shadowmask mode to use from the Quality settings (menu: Edit > Project SettingsA broad collection of settings which allow you to configure how Physics, Audio, Networking, Graphics, Input and many other areas of your Project behave. More info
See in Glossary, then select the Quality category):
See documentation on Mixed lighting and Light modesA Light property that defines the use of the Light. Can be set to Realtime, Baked and Mixed. More info
See in Glossary to learn more about the other modes available.
2017–09–18 Page amended
Shadowmask modes added to Quality Settings in 2017.1 NewIn20171