Bug report #14172
QGIS freezes after canvas refresh when using graduated style with many classes
| Status: | Closed | ||
|---|---|---|---|
| Priority: | Normal | ||
| Assignee: | - | ||
| Category: | Map Legend | ||
| Affected QGIS version: | master | Regression?: | No |
| Operating System: | Easy fix?: | No | |
| Pull Request or Patch supplied: | No | Resolution: | not reproducable |
| Crashes QGIS or corrupts data: | No | Copied to github as #: | 22174 |
Description
We have some layers that make use of the graduated style with many classes (a few hundred). After upgrading from 2.10 to 2.12.0 the projects containing those layers started to misbehave:
A short time (around one second) after the canvas has been updated by a pan or zoom operation, QGIS freezes for a few seconds. The length of the freeze is proportional to the number of classes in the graduated style, regardless of whether the layer is visible. It happens even if the layer is empty.
- Open the sample project
- Select the panning maptool
- Zoom using the mouse-wheel
- Immediately start panning by pressing the left mouse-button and continually moving the mouse
Note that QGIS freezes during the last step for a few seconds (depending on your hardware).
Related issues
History
#1
Updated by Sebastian Dietrich about 8 years ago
- Priority changed from Normal to High
Bisected the bug to 8776449a148e8b5422a73de45e5a364d1a7e5d5d, part of PR 2245, addressing #13078.
#2
Updated by Giovanni Manghi over 7 years ago
- Priority changed from High to Normal
- Status changed from Open to Feedback
- Category changed from Symbology to Map Legend
Hi,
while I can see some kind of lag (not very long to tell the truth, and no freeze) on 2.18.2 I really cannot appreciate the implications as the attached project does have any data (well it has, point?crs=EPSG:4326&memoryid={c97b4801-9e29-4621-998a-1f38d50a422f} but there are no features), so I cannot also say if previously behaved in a different way.
Can you add more data/details? How this impacts real life work?
#3
Updated by Giovanni Manghi about 7 years ago
- Resolution set to not reproducable
- Status changed from Feedback to Closed
Closing for lack of feedback.