https://issues.qgis.org/https://issues.qgis.org/favicon.ico2011-11-12T01:13:17ZQGIS Issue TrackingQGIS Application - Bug report #4514: New symbology fails to render "problematic" lines at high zoom levelshttps://issues.qgis.org/issues/4514?journal_id=263182011-11-12T01:13:17ZSandro Santillistrk@kbt.io
<ul><li><strong>File</strong> <a href="/attachments/download/3542/topotest.png">topotest.png</a> added</li></ul><p>I was wrong about the actual shape.<br />Now made a drawing to represent it.</p> QGIS Application - Bug report #4514: New symbology fails to render "problematic" lines at high zoom levelshttps://issues.qgis.org/issues/4514?journal_id=263192011-11-12T01:19:27ZSandro Santillistrk@kbt.io
<ul></ul><p><img src="https://issues.qgis.org/attachments/download/3542/topotest.png" alt="" /></p> QGIS Application - Bug report #4514: New symbology fails to render "problematic" lines at high zoom levelshttps://issues.qgis.org/issues/4514?journal_id=267902011-12-09T07:42:30ZPaolo Cavallinicavallini@faunalia.it
<ul><li><strong>Category</strong> set to <i>Symbology</i></li></ul> QGIS Application - Bug report #4514: New symbology fails to render "problematic" lines at high zoom levelshttps://issues.qgis.org/issues/4514?journal_id=276722011-12-16T13:10:21ZGiovanni Manghigiovanni.manghi@gmail.com
<ul><li><strong>Target version</strong> set to <i>Version 1.7.4</i></li></ul> QGIS Application - Bug report #4514: New symbology fails to render "problematic" lines at high zoom levelshttps://issues.qgis.org/issues/4514?journal_id=294592012-03-06T00:13:47ZSandro Santillistrk@kbt.io
<ul><li><strong>Affected QGIS version</strong> set to <i>master</i></li><li><strong>Status</strong> changed from <i>Open</i> to <i>Closed</i></li><li><strong>Resolution</strong> set to <i>invalid</i></li><li><strong>Crashes QGIS or corrupts data</strong> set to <i>No</i></li></ul><p>Well, since I was wrong about the shape this ticket is invalid.</p> QGIS Application - Bug report #4514: New symbology fails to render "problematic" lines at high zoom levelshttps://issues.qgis.org/issues/4514?journal_id=294602012-03-06T00:18:56ZSandro Santillistrk@kbt.io
<ul><li><strong>Status</strong> changed from <i>Closed</i> to <i>Reopened</i></li><li><strong>Resolution</strong> deleted (<del><i>invalid</i></del>)</li></ul><p>Actually, since old and new symbology behave differently this is likely still a valid bug.<br />I was looking for this ticket because I had another similar occurrence of it.<br />Lines disappearing on zoom in.</p>
<p>I'm not sure, but it could have to do with lines clipping done in 17e864bb99c5c6b2e1f0493a952870f183d9d9c0 <br />which I think addressed <a class="issue tracker-1 status-5 priority-4 priority- closed" href="https://issues.qgis.org/issues/4088" title="Freeze while rendering labels (master 17e864b) (Closed)">#4088</a> in addition to the reported <a class="issue tracker-1 status-5 priority-5 priority- closed" href="https://issues.qgis.org/issues/4083" title="Line layer labeling eats up all memory (Closed)">#4083</a>.</p> QGIS Application - Bug report #4514: New symbology fails to render "problematic" lines at high zoom levelshttps://issues.qgis.org/issues/4514?journal_id=294612012-03-06T00:43:48ZSandro Santillistrk@kbt.io
<ul></ul><p>Here's another input showing the problem:<br /><pre>
LINESTRING(556267.657697 144886.732981, 556267.657697 144886.732981, 556267.517494 144888.366260)
LINESTRING(556235.246910 144885.298021, 556235.246910 144885.298021, 556254.670000 144886.620000, 556267.657697 144886.732981)
LINESTRING(556267.657697 144886.732981, 556310.040000 144888.170000, 556317.280000 144888.990000, 556328.490000 144888.800000, 556329.964330 144889.104630, 556336.040000 144890.360000, 556354.074605 144896.287433, 556362.830000 144899.280000)
</pre></p>
<p>I hit another bug while trying to reproduce (<a class="issue tracker-1 status-5 priority-4 priority- closed" href="https://issues.qgis.org/issues/5120" title="Crash switching to new symbology (Closed)">#5120</a>) because the problem can't be reproduced with old symbology (or maybe w/out labels, not sure yet).</p> QGIS Application - Bug report #4514: New symbology fails to render "problematic" lines at high zoom levelshttps://issues.qgis.org/issues/4514?journal_id=294702012-03-06T04:17:47ZSandro Santillistrk@kbt.io
<ul></ul><p>Ok, with <a class="issue tracker-1 status-5 priority-4 priority- closed" href="https://issues.qgis.org/issues/5120" title="Crash switching to new symbology (Closed)">#5120</a> fixed the input in previous commit is enough to reproduce <em>this</em> bug. Doesn't need labels, just switching to the new symbology. Zoom on the intersection of the 3 lines to see them moving.</p> QGIS Application - Bug report #4514: New symbology fails to render "problematic" lines at high zoom levelshttps://issues.qgis.org/issues/4514?journal_id=294712012-03-06T04:36:44ZSandro Santillistrk@kbt.io
<ul></ul><p>Note: it renders fine up to scale 1:10, fails at 1:5 and higher</p> QGIS Application - Bug report #4514: New symbology fails to render "problematic" lines at high zoom levelshttps://issues.qgis.org/issues/4514?journal_id=311352012-04-16T04:32:02ZPaolo Cavallinicavallini@faunalia.it
<ul><li><strong>Target version</strong> changed from <i>Version 1.7.4</i> to <i>Version 1.8.0</i></li></ul> QGIS Application - Bug report #4514: New symbology fails to render "problematic" lines at high zoom levelshttps://issues.qgis.org/issues/4514?journal_id=328392012-06-17T10:35:38ZSerge Dikiysdikiy@gisfiber.com
<ul></ul><p>Hi, @strk</p>
<p><a class="external" href="https://github.com/qgis/Quantum-GIS/blob/master/src/core/symbology-ng/qgsrendererv2.cpp#L79">https://github.com/qgis/Quantum-GIS/blob/master/src/core/symbology-ng/qgsrendererv2.cpp#L79</a></p>
<p>New symbology use <a href="http://en.wikipedia.org/wiki/Line_clipping" class="external">Line clipping</a> only if ( nPoints > 100 )</p>
<p>I use a very simple patch to fix the problem :-)<br /><a class="external" href="https://github.com/qgis/Quantum-GIS/pull/179/files">https://github.com/qgis/Quantum-GIS/pull/179/files</a></p> QGIS Application - Bug report #4514: New symbology fails to render "problematic" lines at high zoom levelshttps://issues.qgis.org/issues/4514?journal_id=328402012-06-17T11:02:46ZMarco Hugentoblermarco.hugentobler@sourcepole.ch
<ul><li><strong>Status</strong> changed from <i>Reopened</i> to <i>Closed</i></li></ul><p>The fix is applied, thank you Serge. <br />The symbology-ng line clipping has been made to overcome performance issues with large lines (the Qt clipping itself is too slow). If you say that it also fixes precision problems with shorter lines, that's fine.</p> QGIS Application - Bug report #4514: New symbology fails to render "problematic" lines at high zoom levelshttps://issues.qgis.org/issues/4514?journal_id=328442012-06-17T22:36:30ZSandro Santillistrk@kbt.io
<ul><li><strong>Status</strong> changed from <i>Closed</i> to <i>Reopened</i></li></ul><p>I'd like to have a chance to actually test this.<br />My impression was the "clipping" was the cause of the bug, not the cure.<br />That's based on the fact that "old" symbology (surely not clipping) doesn't suffer from the bug.</p> QGIS Application - Bug report #4514: New symbology fails to render "problematic" lines at high zoom levelshttps://issues.qgis.org/issues/4514?journal_id=328452012-06-17T22:44:25ZMarco Hugentoblermarco.hugentobler@sourcepole.ch
<ul></ul><p>Thanks for your availability to do more tests, that will be helpful.<br />Btw. the old symbology clips linestrings too, but with a different algorithm (see function QgsVectorLayer::drawLineString)</p> QGIS Application - Bug report #4514: New symbology fails to render "problematic" lines at high zoom levelshttps://issues.qgis.org/issues/4514?journal_id=328462012-06-17T23:11:21ZSerge Dikiysdikiy@gisfiber.com
<ul></ul><p>I think this is a bug Qt.<br />This bug appears when the ratio of the line segment to its thickness exceeds a certain value.<br />Bug is not reproduced for the line width greater than 0,3. (I use dataset from original post)<br />Bug is not reproduced for the dotted line style.</p>
<p>"clipping" reduces the length of the line before rendering.</p> QGIS Application - Bug report #4514: New symbology fails to render "problematic" lines at high zoom levelshttps://issues.qgis.org/issues/4514?journal_id=328542012-06-18T04:22:29ZSandro Santillistrk@kbt.io
<ul><li><strong>Resolution</strong> set to <i>fixed</i></li><li><strong>Status</strong> changed from <i>Reopened</i> to <i>Closed</i></li><li><strong>% Done</strong> changed from <i>0</i> to <i>50</i></li></ul><p>Ok, tested. 5b09b96 looks fine to me. Thanks a lot.<br />Would be great to have this case under regression testing.</p> QGIS Application - Bug report #4514: New symbology fails to render "problematic" lines at high zoom levelshttps://issues.qgis.org/issues/4514?journal_id=328552012-06-18T04:41:52ZSerge Dikiysdikiy@gisfiber.com
<ul><li><strong>File</strong> <a href="/attachments/download/4592/QgsRubberBand.PNG">QgsRubberBand.PNG</a> added</li></ul><p>...but QgsRubberBand have same issue.<br /><img src="https://issues.qgis.org/attachments/download/4592/QgsRubberBand.PNG" alt="" /></p> QGIS Application - Bug report #4514: New symbology fails to render "problematic" lines at high zoom levelshttps://issues.qgis.org/issues/4514?journal_id=328562012-06-18T05:04:25ZSandro Santillistrk@kbt.io
<ul></ul><p>do you mean there are still differences between old and new symbology ? That's my main concern, hoping to see one fully replacing the other asap (so to all focus on a single implementation).</p> QGIS Application - Bug report #4514: New symbology fails to render "problematic" lines at high zoom levelshttps://issues.qgis.org/issues/4514?journal_id=330142012-06-26T03:28:56ZSandro Santillistrk@kbt.io
<ul></ul><p>For the record: it was sorted out in IRC that the RubberBand thing has nothing to do with this ticket and that it will eventually need a separate ticket to handle.</p>