Corel Painter Help : Layers : Applying layer masks
Some features described in the Help are available only in Corel Painter 2018, and are not included in Painter Essentials 6. For more information about Corel Painter 2018, visit http://www.painterartist.com/. To get started with Painter Essentials 6, see the Painter Essentials 6 Quick Start Guide.