2.2. QuickMask

The selection tools sometimes show their limits when they have to be used for doing complex drawing selection, as progressive. In this case, using the QuickMask is a good idea which can give very good results.

Overview

To activate the QuickMask click on the left-bottom button showed in red on the screeshot above or select in the image window menu Select/Toggle QuickMask. It can also be activated by using Shift+Q shortcut.

This command generate a temporary 8-bit (0-255) channel, on which the progressive selection work is stored. If a selection is already present the mask is initialized with the content of the selection. Once QuickMask has been activated, the image is covered by a red semi-transparent veil. This one representes the non-selected pixels. Any paint tool can be used to create the selection on the QuickMask. They should use only greyscale color, conforming the channel properties, white enabling to define the future selected place. The selection will be displayed as soon as the QuickMask will be toggled but its temporary channel will not be available anymore.

[Tip] Tip
To save in a channel the selection done with the Quickmask select in the image menu Select/Save to Channel

You can learn more on Quickmask and Selection masks in the section dedicated to the channel dialog.

Usage

  1. Open an image or begin a new document;
  2. Activate the Quickmask using the left-bottom button in the image window. If a selection is present the mask is initialized with the content of the selection;
  3. Choose a drawing tool and use it with greyscale colors on the QuickMask;
  4. Deactivate the Quickmask using the left-bottom button in the image window;