How to tell if a polyline is closed
A polyline is a series of connected line and arc segments. Some applications - in particular CNC - require closed polylines where the polyline start and end points are the same and where there are no gaps in the line and arc series. This tip shows you how to quickly see if a polyline is closed before you export it to another application.
When you vectorize an image using Scan2CAD polylines are displayed in green. Lines within the polyline are displayed in pale green and arcs within the polyline are displayed in dark green. (To toggle between displaying vectors by type or by color, press C on your keyboard.)
If there are no polylines in your vectorized drawing, you can make polylines by selecting Vector Edit Menu > Make Polylines. If there are still no polylines, this is either because the vectors on your drawing are too disjointed to be joined into polylines or because there are Bezier curves (displayed in blue). If there are Bezier curves, close down your vectorization by pressing Ctrl+F8. Go to Type Menu > Settings > Object Identification Tab and make sure that Arc and Polyline are selected. Then revectorize the image.
Once you have a vectorization that contains polylines you can see whether you have a closed polyline as follows:
- Optional: If grab points (squares at vector ends) are displayed, turn them off by pressing G on your keyboard.
- Turn on polyline grab points by pressing P on your keyboard.
Green filled squares appear at the start and end points of polylines. There will be one green square marking the start point of a polyline and one green square marking the end point. If it is a closed polyline there will be just one square marking the start and end point of the polyline.
If there are more green squares than expected, the polyline is broken. The breaks are at the positions of the unexpected green squares.
To mend the polyline, you can either:
Close down your vectorization by pressing Ctrl+F8. Mend the raster image at the polyline break points using Scan2CAD's raster editing tools. Then revectorize the image
Or
Use Vector Edit > UnMake Polylines to break the polylines so they can be edited. Use Scan2CAD's vector editing tools to mend the breaks. Finally, use Vector Edit > Make Polylines to re-make the polylines.
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HINTS & TIPS
A polyline is a series of connected line and arc segments. Some applications - in particular CNC - require closed polylines with no gaps. Click here to find out how to quickly see if a polyline is closed before exporting it to another application.
