418901 - Minor redraw issue using stroke dash array

Status: VERIFIED FIXED

(Core :: SVG, defect)

Description

[Helder "Lthere" Magalhães]

User-Agent:       Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.9b4pre) Gecko/2008022104 Minefield/3.0b4pre
Build Identifier: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.9b4pre) Gecko/2008022104 Minefield/3.0b4pre

(Filed per bug 397362 comment 15.)

A minor redraw issue is sometimes shown using stroke dash array.

Although it is assumed as happening in all Operating Systems, in fact only Windows and Linux were tested (see "Additional Information").

Reproducible: Sometimes

Steps to Reproduce:
1. Open attachment "stroke-dasharray-redraw.svg".
2. Resize the window several times.
Actual Results:  
Contents are resized. In some view port sizes (usually, larger ones), a red
line appears.

Expected Results:  
Contents are (simply) resized.

IMHO this issue is possibly located in the partial redraw mechanism forced by the blinking rectangle, as I haven't been able to reproduce it using the static
test case (attachment "stroke-dasharray-rect.svg").

Versions:
Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.9b4pre) Gecko/2008022104
Minefield/3.0b4pre
Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.9b4pre) Gecko/2008022104 Minefield/3.0b4pre

Comment 1

[Helder "Lthere" Magalhães]

Attachment: static test case

Symptom doesn't seem to occur using this test case. Provided for comparison only.

Comment 2

[Helder "Lthere" Magalhães]

Attachment: dynamic test case

Symptom is observed using this test case.

Comment 3

[Helder "Lthere" Magalhães]

Attachment: dynamic test case animation

Attached file is an animated PNG (APNG): one should be able to see the described behavior (when using Firefox 3+ and/or Opera 9.5+).

(On the other hand, the blink showns an apparent bug in Firefox implementation of APNG - bottom portion of the window used in screen shot blinks. This seems a new and separate issue and was filed as bug 418848.)

Comment 4

[Helder "Lthere" Magalhães]

There seem to be some improvements, possibly due to bug 446323 been fixed. It's now harder to reproduce the issue.

Some view port sizes where the symptom was still experienced (easily extracted using Web development toolbar [2] "Resize"->"Display Window Size") follow.

Viewport width: 353px
Viewport height: 135px

Viewport width: 489px
Viewport height: 270px

Viewport width: 670px
Viewport height: 281px

Viewport width: 709px
Viewport height: 287px

[1] https://bugzilla.mozilla.org/show_bug.cgi?id=446323
[2] http://chrispederick.com/work/web-developer/

Comment 6

[Daniel Holbert [:dholbert]]

See also attachment 336209 [details], which shows similar issues when you drag other windows across it.  (see bug 452977 for more info)

Comment 7

[Daniel Holbert [:dholbert]]

(In reply to comment #6)
> See also attachment 336209 [details]
... and attachment 336211 [details], a screenshot of the bug using that attachment

Comment 8

[Jeff Muizelaar [:jrmuizel]]

It looks like this is fixed by the 444d44acde4ac73641c789c19ec7a3199211b594 commit in the cairo repo. However it hasn't been upstreamed yet.

Comment 9

[Jeff Muizelaar [:jrmuizel]]

This has been fixed in ce976e0708ab

Comment 10

[Helder "Lthere" Magalhães]

Great. :-) Wasn't able to reproduce the issue using a nightly build, so marking as verified until proved otherwise.

Version details:
Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.9.1b3pre) Gecko/20081214 Shiretoko/3.1b3pre