Hi - just a question to my understanding .....
What is the exact difference between a closed or not closed Polyline?
If I draw a Polyline (i.e. Rectangle shape) and finish this rectangle with an exact end snap point to the start of the Polyline - the property editor tells me this Polyline isn't closed.
If I use the Option Bottom "close Polyline" the property editor tells me it is closed.
If I draw an offset line based on this closed Polyline - the offset will be not closed ....
What is the secret of this closed yes/no information ......
Closed Polyline or not ....
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Re: Closed Polyline or not ....
This originates from the DXF / DWG file formats. These formats define an open/closed flag for polylines.
A rectangle formed from a closed polyline only needs four vertices, whereas an open polyline would require five vertices to form a closed rectangle.
For most purposes, the end result is the same (a closed rectangle).
The only case I can remember in which it does make a difference is if the file produced by QCAD will be processed further by other software. There are certain types of machine controllers for example in electron-beam-lithography that treat properly closed polylines differently.
A rectangle formed from a closed polyline only needs four vertices, whereas an open polyline would require five vertices to form a closed rectangle.
For most purposes, the end result is the same (a closed rectangle).
The only case I can remember in which it does make a difference is if the file produced by QCAD will be processed further by other software. There are certain types of machine controllers for example in electron-beam-lithography that treat properly closed polylines differently.
Re: Closed Polyline or not ....
Now I have an good Idea what the difference is - thanks for explaining it to me.