Bug report #13742

Strange polygon edge rendering at edges of visible extent

Added by Paulo Raposo over 8 years ago. Updated over 8 years ago.

Status:Closed
Priority:Normal
Assignee:-
Category:Map Canvas
Affected QGIS version:2.12.0 Regression?:No
Operating System:Windows Easy fix?:No
Pull Request or Patch supplied:No Resolution:fixed/implemented
Crashes QGIS or corrupts data:No Copied to github as #:21769

Description

I'm using QGIS 2.12 "Lyon", Windows 7, 8, and 10, though it happened under "Pisa" too.

Particularly with larger, more complex polygon shapefiles, there are erroneous lines added to polygon edges, usually around the edges of the visible extent. They're temporary, and dissappear when I zoom or pan - either that, or new, different temporary ones appear! I attached a screenshot where every shape should be either square or rectangular, only 90 degree angles, yet there are seemingly random diagonal lines here and there around the visible edges. Pretty disconcerting, cartographically speaking.

They don't seem to happen in the print composer, but I'm not working with it as much.

Thanks :)

weirdrendering.png (140 KB) Paulo Raposo, 2015-11-02 05:27 PM

qgis_main_window.png - Main window shows artifacts (57.7 KB) Paulo Raposo, 2015-11-08 12:52 AM

printcomposer.png - Print composer shows artifacts (54.3 KB) Paulo Raposo, 2015-11-08 12:52 AM

printcomposer_export.png - Export is correct (41 KB) Paulo Raposo, 2015-11-08 12:52 AM

clean.png - Seems all clear here. (1.16 MB) Paulo Raposo, 2015-11-15 09:37 PM

History

#1 Updated by Paulo Raposo over 8 years ago

#2 Updated by Nyall Dawson over 8 years ago

  • Status changed from Open to Feedback

Likely a duplicate of #13343. It's been fixed since 2.12. Can you test the nightlies and confirm?

#3 Updated by Giovanni Manghi over 8 years ago

  • Target version deleted (Version 2.12)

#4 Updated by Paulo Raposo over 8 years ago

Hmm, does look similar to 13343. But it's happening not just with "long" lines. Happens to me with polygons. It's still happening to me now in 2.12 (Lyon), and has in previous versions back to Wien too. Haven't been able to check nightlies yet; might have a problem with that if I have to compile them myself (haven't learned how to do that yet). I attach new screen caps; seems it's happening in the print composer too, but not the exported png.

#5 Updated by Giovanni Manghi over 8 years ago

Paulo Raposo wrote:

Hmm, does look similar to 13343. But it's happening not just with "long" lines. Happens to me with polygons. It's still happening to me now in 2.12 (Lyon), and has in previous versions back to Wien too. Haven't been able to check nightlies yet; might have a problem with that if I have to compile them myself (haven't learned how to do that yet). I attach new screen caps; seems it's happening in the print composer too, but not the exported png.

On Windows you don't need to compile, just use the osgeo4w installer and you'll daily updated of the development version. Please give it a try and report back (or attach sample data). Obrigado!

#6 Updated by Paulo Raposo over 8 years ago

Hi, sorry for delay. Used OSGeo4W as suggested, installing "qgis-rel-dev" option, version 2.12.0-10 nightly build. The problem seems to be gone (hurray!). Screen-cap attached.
Above, you folks say "It's been fixed since 2.12" -- as in, after 2.12 was released? Because it's happening on my copy of 2.12 installed through the qgis.org installer, but not on this nightly build. Windows 10 64-bit, btw.

#7 Updated by Nyall Dawson over 8 years ago

  • Status changed from Feedback to Closed
  • Resolution set to fixed/implemented

Sorry, I meant "fixed after 2.12". So this issue is still present in 2.12, but not later versions.

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