work area for forming the region.
	tools for forming the region.

The work area shows the current layer in which the region is being formed. The layer is shown with the selected region if one has already been formed. The areas of the layer not included in the region are semi-transparent, and the areas included in the region are completely opaque. A region can be formed with the help of two modes: "Tolerance" and "Lasso". The "Tolerance" mode is active by default and the "Lasso" mode is activated by clicking on "Lasso" icon .

The basis for the "Tolerance" mode is the selection of a colour range in the layer. The extent of the colour range is assigned using the "Colour tolerance" slider. To add a colour range to the region being created, first click on the colour in the layer which you want to select. To add a new colour range, click on the colour while holding down the Shift key. To remove a colour range from the region, click on the colour while holding down the Alt key. If you change the value of the colour range with the "Colour tolerance" slider while holding down Shift, the region will dynamically change according to the new colour range. To make an inversion of the region you have formed, right-click on it while holding down Ctrl. If you click on the layer while pressing both Ctrl and Shift, the whole colour range of the layer or grid cell (see below) will penetrate into the region. If you click on the layer while pressing Ctrl and Alt, all colour ranges will be removed from the region or grid cell (i.e. the region will be cleared).

"Grid" displays a grid in the work area. You can change the size of the cells in the grid by using the "Grid rows" and "Grid columns" sliders. The grid allows you to delimit the area selected when you’re forming a region using the "Tolerance" function.

The "Lasso" function allows you to select any area of the layer. The cursor assumes the form of a lasso. If you now move the cursor in the work area while pressing down the left mouse button, you can use the red line that outlines the selected area. When you are satisfied with the area selected, just let go of the mouse button. To exclude an area from the region, repeat the same operation but keep the right mouse button pressed down.

"Clear region" clears the current region.

"Work with selected region on/off" causes any changes made beyond the limits of the selected region to be ignored while you’re in the process of forming the region with the "Tolerance" function.