2.5 Masks Tab
From 3D-Coat Wiki
Masks are used as a way to specify an area for sculpting or texture painting for pen depth and transparency. The basic principle of a stencil is the idea here. The mask and materials could be moved and rotated independently using new navigation controls. Masks and materials could be rotated discretely on 45 degrees using SHIFT.
Pay attention, if you choose to display mask/material in at least one of the channels (depths and/or, colors and/or specular, see more detail about them below) a new panel shows up on top. Using this panel you can manage the Masks/material preview parameters:
Hide/Show/Auto. Hide/show/auto-hide full-screen view of texture. You can switch regimes with the hot key “H”. Unlock/ Lock. Allows to scale and texture automatically while scaling and moving the model.
Flip X. Flip X. Reflect texture mirror-like across.
Flip Y. Reflect texture mirror-like along vertical axes.
Distort Image. In this mode you can distort your mask or material directly with your brush. You can get some very unique texture work done with this feature. It is great to use when you have an image that doesn’t match the mesh exactly.
Then you can use this tool, to shape it to match the mesh more precisely so that you can then paint with a material or mask. As you can see in the image, the jaw line, nose and silhouette of the head has been shaped with the distort image feature.
Reset. Place texture in initial position.
Clear/Save/Load Distortion. With these options you to clear, save and load your distortions. Each one is self explanatory.
Mapping Method. There are two methods with which you can use here. “From Camera” and “Cube Mapping”.
From Camera allows you to project the method through the viewport. If the “cube mapping” application type is selected, the material preview will be displayed on pen only, as opposed to full screen (when “From camera” is selected). To the right there is a slider responsible for transparency when viewing the Masks/material.
Opacity of preview. Percentile based opacity controls. Adding a new mask or material is done exactly as you do with Pens and Strips.