Creation of line object

The line object of a digital map contains coordinates of two and more vertexes.

The line object can be closed or non-closed, to have some constituents (subobjects), spatially to be connected to other objects of a map and is logically connected to one or several records  of the external database.

Depending onto its type line object can be created as one of following:

- as an object of arbitrary configuration;

- as a horizontal, rotated or complex rectangle;

- as a circle of fixed or arbitrary radius;

- during a semi-automatic vectoring (tracing) of a raster;

- is loaded (coordinates) from a text file;

- is entered (coordinates) from the keyboard;

- as a parallel line (tube) with an axis along a line or along the left edges;

- as an envelope or smoothing spline;

- creation of objects group by coordinates from the file.