Serves for controlling parameters of selection circles in the mode Select by circle.
The window is opened automatically when the mode Select by circle is chosen and it is closed when any other mode is chosen.
To select all features lying in some circle (selection circle) it is necessary to indicate this circle in displaying pane. To do this it is required to place the cursor in the center of the circle and push the left mouse button. Then move the cursor on the circle boundary while holding down the left mouse button and then release the button. All the features in the circle are selected, the rest features are deselected.
To select features in selection circle without deselecting other features (selected before) it is necessary to hold down the key Ctrl at the moment of releasing the left button.
To deselect features in selection circle without changing the state of features selected before it is required to hold down the key Alt at the moment of releasing the left mouse button.
To reverse the state of selection of features in the circle it is required to hold down the combination of keys <Ctrl+Alt> at the moment of releasing the left mouse button.
To leave in selected state only the features which were selected already and which are lying in the built circle it is required to hold down the key Shift at the moment of releasing the left mouse button.
Degree of falling of the feature into selection circle with which the feature is considered to be lying in this circle (selection threshold) is one of theme properties and can be regulated from 0 to 100%.
Clicks by the left mouse button allow selecting and deselecting separate features similarly as in the mode Select.
Center | Shows the current value of X and Y coordinates of cursor when choosing the center of selection rectangle. |
Radius | Shows the current value of selection circle radius. |
Length | Shows the current value of length of selection circle and also the total value of all selection circles built before plus the length of the current circle. |
Area | Shows the current value of selection circle area and also the total value of areas of all selection circles built before plus the area of the current circle. |
Reset | Resets previously accumulated values of total length and total area of selection circles to zero. Only current values of length and area are retained. |
Modes of selecting by rectangle, circle, polyline or polygon
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