I'm a bit stumped on this.  I have some polygons in a postgis layer with spikes 
into the interior.  The spikes are an exact retrace going into and back out 
(the digitizers never completed the line to another edge of the polygon to 
split it into 2 polygons).  The node edit tool shows many, but not always all, 
nodes along the spike with problems, I think it depends on how many other node 
errors are on other parts of the polygon.  They exist in the layer fine, but I 
can't do any geometry operations like merge or split (nothing happens), though 
I can move/add/delete vertices.  I need to extend the "spike" to split the 
polygon.

<<inline: Screen shot 2011-03-29 at 8.39.21 AM.png>>

<<inline: Screen shot 2011-03-29 at 8.52.53 AM.png>>


I tried exporting to a line shapefile (Vector->Polygons to Lines), where a 
split will will work to separate the spike from the outer ring, then I extend 
the line and eventually create 2 polygons, which I can copy-n-paste back to the 
original polygon layer, but I ran into invalid geometry types:

http://trac.osgeo.org/qgis/ticket/3604

Any other ideas?  I don't want to retrace the whole spike, as some are very 
long.  Or is this a bug in handling invalid geometry?

-----
William Kyngesburye <kyngchaos*at*kyngchaos*dot*com>
http://www.kyngchaos.com/

All generalizations are dangerous, even this one.


_______________________________________________
Qgis-user mailing list
[email protected]
http://lists.osgeo.org/mailman/listinfo/qgis-user

Reply via email to