topic Re: hidden lines in an OS map in AutoCAD Forum

hidden lines in an OS map

Luke_Daniels — Sun, 07 Sep 2025 12:18:37 GMT

At some point this entire OS map has been copied multiple times onto itself so every one of the 1000s of lines it holds has numerous hidden lines underneath which is making it appear darker and thicker than it actually is. FLATTEN command is not working as a means of removing all the hidden lines so I need a way of selecting only the top version of each line in order to move them before blocking them and deleting the rest. Save for clicking on each on individually I cannot come up with a way to do this as both left and right windows will select everything. Any ideas welcome...

Re: hidden lines in an OS map

imadHabash — Sun, 07 Sep 2025 13:01:45 GMT

Hi,

Try with OVERKILL command. >> Click <<

BTW...
FLATTEN command changes the Z-values of selected lines, arcs, and polylines to 0.

So, While flatten command is active... Remove hidden lines? [Yes/No] .... means the follow :

Yes = creates a simplified 2D view with only visible edges.
No = creates a “wireframe-like” 2D result with all edges visible.

Re: hidden lines in an OS map

Luke_Daniels — Mon, 08 Sep 2025 08:43:15 GMT

Hi Imad,
Overkill has worked to a degree though there are still remaining multiple lines within the OS map, (thousands in total) Do you have any further suggestions to remove these leaving only a single iteration of each line in the map...

Re: hidden lines in an OS map

imadHabash — Mon, 08 Sep 2025 08:49:38 GMT

For me,

If you want to use certain commands or lisps, certain conditions must be met to achieve impressive results. For that I usually do this task manually.

With select lines and use Shift+select to deselect objects i can manage it.

Re: hidden lines in an OS map

pendean — Mon, 08 Sep 2025 12:39:01 GMT

@Luke_Daniels Share your actual DWG file here please.

Re: hidden lines in an OS map

Luke_Daniels — Mon, 08 Sep 2025 12:46:17 GMT

attached for you as requested...