Selection and Edit Commands

The selection of graphical objects is based on standards used in MS Office. An object is selected by clicking the left mouse button; a multiple selection is made by simultaneously holding the Shift button. A selection can be made using a rectangle (by clicking with the left mouse button outside of objects and holding the left mouse button while moving the mouse), rhomboid (see Chapter 8.4. on Toolbars and Tools, with the Edit->Select->Select by Rhomboid command), circle (Edit->Select->Select by Circle) or polygon  (Edit->Select->Select by Polygon).

In the Standard Selection Mode (Edit->Select->Standard Selection Mode) the status of the selected object is changed (selected or unselected) after its selection, i.e., the selection is toggled. If we want to only add or remove objects to or from existing selection (i.e., we want to prevent switching the status of selected objects (toggling)), respectively, it is possible to choose two special selection modes: “Add to Selection” (Edit->Select->Add to Selection) or “Remove from Selection”.  (Edit->Select-> Remove from Selection). Both commands are accessible from the submenu Edit->Select or from the toolbar under the button “Tools for Selection”. Two special Selection Modes can also be activated by holding the “Left Ctrl” (Add to Selection) or “Right Ctrl” (Remove from Selection) keyboard buttons.

When the cursor (mouse) is moved above an object, information about that object appears on the status bar and the object is temporarily highlighted; this process is referred to as pre-selection. Apart from selecting objects graphically, they can also be selected using their Indices or by means of Sections.

Double-clicking on selected objects or simultaneous holding the Alt+Enter buttons recalls dialogs for editing properties of particular objects. Most dialogs support multiple editing, i.e., if edit boxes with different values remain empty, the original values will not change. This feature allows for example Z-coordinates of multiple selected points to be changed, while leaving the X- and Y-coordinates unchanged.

When different objects are selected simultaneously (e.g., points and curves), double clicking causes a dialog window to appear from which objects can be selected for editing