Bug report #21458

rendering cycles forever when viewing raster at certain scales

Added by Tony Walters about 5 years ago. Updated about 5 years ago.

Status:Closed
Priority:Normal
Assignee:-
Category:Rasters
Affected QGIS version:3.6.0 Regression?:No
Operating System:Win 10 Easy fix?:No
Pull Request or Patch supplied:No Resolution:not reproducable
Crashes QGIS or corrupts data:No Copied to github as #:29275

Description

High resolution raster (LiDAR 1m) causes rendering to cycle forever. Example of Scales that exhibit the behaviour:

1:2556 - ok
1:5111 - bad
1:81777 - ok

Windows 10
16GB ram
Nividia Geforce

Problem started from version 3, and continues in version 3.6

History

#1 Updated by Giovanni Manghi about 5 years ago

Not sure is related, but in a recent training based on 3.4.5 I have seen a lot of installation simply stop to show anything on map while the progress bar at the bottom seemed to indicate that qgis was loading something. The projects where very simple with just a few vector and raster layers, light stuff. Only solution? restart qgis, not pretty.

#2 Updated by Giovanni Manghi about 5 years ago

  • Status changed from Open to Feedback

does it happen with any raster?

#3 Updated by Tony Walters about 5 years ago

Hello,

I loaded up a couple of 30m elevation rasters and they work as normal. I also loaded up 2 more LiDAR 1m elevation raster and they exhibit similar behaviour.

LiDAR 1 LiDAR 2
1:2556 good 1:1364 good
1:5111 bad 1:2729 bad
1:81777 good 1:87321 good

LiDAR 3
1:2047 good
1:4093 bad
1:8186 bad
1:16373 bad
1:32745 bad
1:65491 bad
1:130982 good

Cheers,
Tony

#4 Updated by Giovanni Manghi about 5 years ago

Tony Walters wrote:

Hello,

I loaded up a couple of 30m elevation rasters and they work as normal. I also loaded up 2 more LiDAR 1m elevation raster and they exhibit similar behaviour.

LiDAR 1 LiDAR 2
1:2556 good 1:1364 good
1:5111 bad 1:2729 bad
1:81777 good 1:87321 good

LiDAR 3
1:2047 good
1:4093 bad
1:8186 bad
1:16373 bad
1:32745 bad
1:65491 bad
1:130982 good

Cheers,
Tony

can you attach/link sample data?

#5 Updated by Tony Walters about 5 years ago

Here is one of them.

https://we.tl/t-BouzBWxDay

I don't think this is related but for certainty: I have many layers, only a few selected at a time. The system starting from 3.0 has been very sluggish, sometimes taking minutes to render. In order to eliminate my laptop as a factor, I have ordered a 6 core processor desktop with 32GB RAM and Geforce graphics. Should arrive in a week or so. Then I will do a new install of QGIS and see if there is a change.

#6 Updated by Giovanni Manghi about 5 years ago

Tony Walters wrote:

Here is one of them.

https://we.tl/t-BouzBWxDay

I can't see any issue on 3.6 on both Linux and Windows on this layer, at any scale.

#7 Updated by Tony Walters about 5 years ago

`Update: I have upgraded to a new Intel 8700 PC with 32GB ram and Geforce graphics. The sluggishness is not apparent on this new system. We should close this now. Maybe this was some kind of corruption on the old laptop. Thx for the assistance.

#8 Updated by Giovanni Manghi about 5 years ago

  • Resolution set to not reproducable
  • Status changed from Feedback to Closed

Also available in: Atom PDF