To change an existing line feature it is necessary to switch over to the mode Edit (the button 
) and select the feature for editing by clicking on it (or select the feature first and then switch over to the mode of editing). Eight white small squares – resizing handles will be displayed around the line feature selected for editing. Handles are located in the corners and in the middle of sides of the box bounding the feature.
It is possible to select several features for editing at once. To do this it is necessary to select these features one by one clicking on them while holding down the key Ctrl in the editing mode, or select the features using any method described in chapter 13 “Feature selection” and then switch over to the editing mode. The group of selected features will be changed as a whole. Resizing handles are located in the corners and in the middle of the sides of the minimal rectangle bounding all selected features.
The current parameter values of the feature being edited can be seen on page “Information” of the window “Editor control”.
If the submode Editing vertices is turned off (the button 
) it is possible to perform the operations of editing in which a line feature is considered as a single whole. The following operations can be named here:
Moving a feature or group of features. It is performed by “dragging”: it is required to place the cursor to the feature polyline or close to it (the cursor should take the form of 
), press the left mouse button, move the cursor to a new position (moved features are displayed in the form of thin gray polylines) and release the button thus completing the moving operation.
Resizing of a feature or group of features. To do this the user should place the cursor on one of resizing handles (the cursor takes the form of a bi-directional arrow) and while holding down the left mouse button drag the handle to a new position thus changing the sizes of the bounding box. The size of the feature itself is changed accordingly. If a group of features is selected for editing, all the features change their sizes and position proportionally to the bounding box changes.
If a box Keep proportions is checked in the window “Editor control” when handles are moved, the ratio of the height of the rectangle to its width will always remain unchanged.
Rotating a feature or group of features around the specified center. To do this it is required to turn on the submode Rotating feature (the button 
) remaining in the mode Edit. In the corners of the box bounding the feature (or group of features) green circle handles will appear, and in the center of the feature bounding box the rotation center – a gray point in a circle will be displayed. This center can be dragged to any position holding the left mouse button down. Then the cursor should be placed on a green handle (the cursor takes the form of 
) and it becomes possible to rotate the feature (or group of features) around the specified rotation center holding down the left mouse button.
If the cursor is located not on the rotation handle, but on the feature itself, instead of feature rotation, feature dragging to an arbitrary point will be performed (as when the submode Rotating feature is turned off). The rotation center is moved with the feature.
Removing a feature or group of features. It is enough to press the key Delete to remove the selected features.
To change the shape of the line feature the submode Editing vertices of the mode Edit should be used. To do this it is necessary to push the button in the mode toolbar. Only one feature, not a group of features, should be selected. In all vertices of the edited feature handles of moving vertices in the form of small white squares will appear. The following operations can be performed in this submode:
Marking a group of vertices for subsequent operations. The marked polyline vertex is displayed with a handle in the form of a small black square. There are several methods of setting and removing markings: on one vertex, on two neighboring vertices, on all vertices of a feature, and also on all feature vertices within the specified rectangle.
To mark one feature vertex it is necessary to click the handle of this vertex. It is possible to mark several vertices clicking on their handles while holding down the key Ctrl. The marking can be removed by clicking the handle holding down the key Alt.
If the click is performed when the cursor is placed on the segment between the vertices, both vertices connected by this segment are marked (or holding the key Alt down the marking is removed).
A double click on the vertex or the segment results in marking of all the vertices of the present line feature.
To mark several vertices at once it is possible to specify a rectangle on the screen by pressing the mouse button in one corner of this rectangle and releasing the button in the opposite corner. In this case all the vertices of the feature being edited which fall into the specified rectangle will be marked.
Keys Ctrl and Alt in all the cases modify the operation performed in a usual way.
Moving a vertex or group of vertices. To change the vertex position it is enough to place the cursor on this vertex and drag the handle to a new position while holding down the left mouse button. If several vertices were marked before, it is necessary to place the cursor on any of them and drag all the group of vertices to a new position.
Adding a vertex or group of vertices. The simplest way to add one new vertex between the two existing ones is to place the cursor on the corresponding polyline edge (the cursor takes the form of 
), press the left mouse button and move the cursor to the position of the new vertex.
If several vertices should be added at once, it is more convenient to mark two neighboring vertices beforehand and call the context menu command Add Group of Vertices. After that the vertices are added like in the mode of adding a feature by clicking in the positions of vertices being added. The status of the checkbox Inverse input of vertices determines one of the two marked vertices with which the first added vertex will be connected by a boundary segment. The second marked vertex will be connected with the last added vertex by a dotted line. Adding a group of features is completed by a double click, and the dotted line is replaced by the boundary segment.
If it is necessary to add one or several vertices outside the outermost polyline vertex, this outermost vertex should be marked and the command Add Group of Vertices performed.
Rotating a vertex or group of vertices around the specified center. To perform this operation it is required to switch on the mode Edit, submodes Editing vertices and Rotating feature, select one feature for editing and mark one or several vertices of this feature. In this case the marked vertices are shown by handles in the form of green circles, and the rotation center – by a gray point in a circle. The user can drag the rotation center to the necessary position and then placing the cursor on any of these green handles and move the marked vertices along concentric circles around the rotation center while holding down the left mouse button.
Removing a vertex or group of vertices. To remove the marked vertices it is enough to press the key Delete or perform the command Delete of the context menu.
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