1662062 - Scalable vector graphics files gets distorted if zoomed in using pinch-to-zoom

Status: RESOLVED FIXED

(Core :: Graphics: WebRender, defect)

Description

[adummyuser]

Attachment: A screenshot of the bug.

User Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:78.0) Gecko/20100101 Firefox/78.0

Steps to reproduce:

1. Open any scalable vector graphics file.
2. Zoom in on the file using pinch-to-zoom to the maximum allowed.

Actual results:

The edges of the SVG file gets distorted.

Expected results:

The SVG file shouldn't get distorted when zooming in and instead smooth out the edges.

Comment 1

[Clara Guerrero ( Need Info Brindusa Tot Please)]

Hi adummyuser,

I'm trying to reproduce this issue using windows 10 pro, firefox nightly 82.0a1 (2020-09-04) (64-Bit), beta 81.0b4 and release 80.0, reached 300% zoom, borders don't look distorted.

I used this testing file https://mime.ty.ax/dl/test.svg?ty=svg&ct=image%2Fsvg%2Bxml&cd=attachment

Please test if the issue occurs to you in safe mode (add-ons disabled). Here is a link that can help you do that:
https://support.mozilla.org/en-US/kb/troubleshoot-firefox-issues-using-safe-mode
Also, can you try this on the latest version of nightly? You can download it from here: https://nightly.mozilla.org/

I will move this over to a component so developers can take a look over it. If is not the correct component please feel free to change it to an appropriate one.

Thanks for the report.

Best regards, Clara.

Comment 2

[Timothy Nikkel (:tnikkel)]

I can reproduce but only with webrender. Furthermore, after pinch zooming in it is easy to get checkerboarding by pan to the right, and you even get a checkerboard left effect on the right side when panning left.

Comment 3

[Timothy Nikkel (:tnikkel)]

The bluriness exists at least as far back as 2018-12-01, before that pinch zoom in the desktop browser isn't really in a usable state it seems.

Comment 4

[adummyuser]

Hello, Clara

You may have been using the normal zoom function instead of pinch-to-zoom which only is currently available on Nightly.

I have downloaded and opened the file you used to test and the borders still look distorted. I also refreshed Firefox but the issue is still there. But when I started Firefox in Safe mode, the issue doesn't appear anymore. I haven't installed any extensions ever since I installed Nightly on my computer.

Comment 5

[adummyuser]

Update: The issue doesn't seem to happen anymore on the latest version of Nightly (2020-09-11).

Comment 6

[adummyuser]

The issue now only appears when I enable webrender. Previously, the issue appears even when webrender is disabled.

Comment 7

[Timothy Nikkel (:tnikkel)]

Attachment: Bug 1662062. Make StackingContextHelper constructor handle pinch zooming resolution when calculatoring the scale. r?jrmuizel

Looks like it's just a case we missed. This affects on desktop and android.

Comment 8

[Timothy Nikkel (:tnikkel)]

Bug 1678515 is filed for a weird rounding (?) issue I ran into writing a test for this. (I was able to avoid the issue though by changing the test slightly.)

Comment 10

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/774fb7eed629
Make StackingContextHelper constructor handle pinch zooming resolution when calculatoring the scale. r=jrmuizel

Comment 11

[Dorel Luca [:dluca]]

Backed out changeset 774fb7eed629 (bug 1662062) for Build bustages in StackingContextHelper.cpp. CLOSED TREE

Log:
https://treeherder.mozilla.org/logviewer?job_id=322921797&repo=autoland&lineNumber=19585

Push wtih failures:
https://treeherder.mozilla.org/jobs?repo=autoland&group_state=expanded&revision=774fb7eed629431765c3991deb25326c00156d79

Backout:
https://hg.mozilla.org/integration/autoland/rev/43cc31d4bf1d5fa50c7f90d7f864aada1e570db0

Comment 12

[Timothy Nikkel (:tnikkel)]

Weird, must have been some change in unified building includes or something? I'll add an include that should fix this and test it on try and then reland.

Comment 13

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/194ca0c692cd
Make StackingContextHelper constructor handle pinch zooming resolution when calculatoring the scale. r=jrmuizel

Comment 14

[Razvan Maries]

https://hg.mozilla.org/mozilla-central/rev/194ca0c692cd