Topology
The Topology submenu can be found in the Object menu.
Join
Choose the Join function in the Topology submenu of the Object menu or in the Edit Functions Toolbar. This function is active if a line object is selected.
Use this function to adjust adjoining line ends so that they coincide. Only line objects with the same symbol are joined. This is especially useful when continuing a line object such as a contour. Note that the objects remain independent objects, but the coordinates of the end vertices are equalized. If you want to merge objects, choose the Merge command.
Automatic Joining
If you enable Automatic Joining in the Edit Functions Toolbar, end points of lines are joined automatically when finish drawing a line near another line end.
Tolerance Value
Define how close two line end points have to be for joining them in the Drawing and Editing category of OCAD Preferences.
Select Duplicate Objects
Choose this function from the Topology submenu of the Object menu.
With this function you can find all duplicate objects. The objects must be identical and on the same position that they can be found.
Objects with different symbols whose geometry is identical are not selected.
Select Self-Intersected Objects
Choose this function from the Topology submenu of the Object menu. This function selects all line, area and line text objects with a self-intersecting geometry. The selection can be saved right after carrying out the command (Save a Selection).
Select Line Text Objects with too Short Line
This command selects all line text objects whose text is longer than the line length. This may happened when the text symbol's font size was increased.
Close Area Objects
ToDo
Remove Overshoots and Undershoots
ToDo
Insert Intersections
ToDo