if you're going to select the lines one by one anyway, you might as well pick a point rather than select the lines:
Well, reasons:
1) the drawings are not as neat as this sample. Other lines, texts, dims, ect..will cross the figure. If pick points to "region", I need to "layer-off" those unrelavant layers, after that, "layer-on". Not that convenient as "ssget" with filters.
2) there might be some small gaps between lines' intersections. I can use the (inters ... nil) to negelect those gaps by allowing some distance errors. While the "region" will fails.
3) Actually, by apply the (command "pedit" ...), I now can achive the area. But I am still curious about the way without "command", like the Lee's Pointarea. That would be nice:)
Hope this can help ur undersanding.
I am trying a method to rearrange the intersections that collected by ur code :
(setq pts_ (cons (list (cdr (assoc 10 ent))
(cdr (assoc 11 ent))) pts_)))
That is:
select an arbitrary line -> (setq ptlst (list p0 p1)) -> use p0 to search for the next line (p0, p2) -> (cons p2 ptlst) -> use p2 to search for next (p2,p3).......
Maybe it would work
Thank you!