Bug 431847 - Slow Rendering of PDFs (comparing to other rendering engines).
Summary: Slow Rendering of PDFs (comparing to other rendering engines).
Status: RESOLVED UPSTREAM
Alias: None
Product: okular
Classification: Applications
Component: PDF backend (show other bugs)
Version: 20.12.1
Platform: Arch Linux Linux
: NOR normal
Target Milestone: ---
Assignee: Okular developers
URL:
Keywords:
Depends on:
Blocks:
 
Reported: 2021-01-20 12:20 UTC by Jack
Modified: 2021-01-21 06:04 UTC (History)
2 users (show)

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Description Jack 2021-01-20 12:20:17 UTC 
SUMMARY
Okular renders very slowly comparing to the other rendering engines.

STEPS TO REPRODUCE:
1. Load any avarage PDF (30-40 pages, lots of text, some small-ish photos)
2. Scroll intensively
3. Compare the speed to muPDF-gl version
The difference between Okular (slow) and muPDF-GL (instantenous) is quite huge.


EXPECTED RESULT
Fix for instantenous render like the competition.

SOFTWARE/OS VERSIONS

Linux/KDE Plasma: Arch
(available in About System)
KDE Plasma Version: 5.20.5
KDE Frameworks Version: 5.78.0
Qt Version: 5.12.2
Comment 1 Albert Astals Cid 2021-01-20 21:01:27 UTC 
Okular doesn't do any rendering. The rendering happens at the poppler level.
Comment 2 Oliver Sander 2021-01-21 06:04:57 UTC 
In any case, this report is too unspecific.  I am not saying that what you say is wrong, but a report that can be acted upon must be more specific.  For example: "poppler renders this particular page from this particular document much slower than mupdf".