437106 - Bad SVG rendering when element referenced by <use> comes after the <use>

Status: RESOLVED FIXED

(Core :: SVG, defect)

Description

[Fabrice TIERCELIN]

User-Agent:       Mozilla/5.0 (Windows; U; Windows NT 5.1; fr; rv:1.9) Gecko/2008051206 Firefox/3.0
Build Identifier: Mozilla/5.0 (Windows; U; Windows NT 5.1; fr; rv:1.9) Gecko/2008051206 Firefox/3.0

Here is an example of a badly rendered .svg file (Scalable Vector Graphics) :
http://upload.wikimedia.org/wikipedia/commons/1/17/Construction.svg

Reproducible: Always

Steps to Reproduce:
1. Go to http://upload.wikimedia.org/wikipedia/commons/1/17/Construction.svg
Actual Results:  
http://upload.wikimedia.org/wikipedia/commons/1/17/Construction.svg

Expected Results:  
http://upload.wikimedia.org/wikipedia/commons/thumb/1/17/Construction.svg/48px-Construction.svg.png

This problem may concern more .svg files.

Comment 1

[Ria Klaassen (not reading all bugmail)]

There is at least one regression range: 
http://bonsai.mozilla.org/cvsquery.cgi?module=PhoenixTinderbox&date=explicit&mindate=1184125200&maxdate=1184129639
This is the range when it really stopped working. But before that range I saw it also sometimes not working. 
The problem seems to have started on 6 May but I'm not 100% sure.
I believe I've seen this kind of bug before.

Comment 2

[Ria Klaassen (not reading all bugmail)]

6 May range would be http://bonsai.mozilla.org/cvsquery.cgi?module=PhoenixTinderbox&date=explicit&mindate=2007-05-05+21%3A00&maxdate=2007-05-06+23%3A00

Comment 3

[Boris Zbarsky [:bzbarsky]]

Attachment: Testcase that shouldn't be timing or size-dependent

Comment 4

[Boris Zbarsky [:bzbarsky]]

Someone who actually knows SVG should be able to create a simple DOM-mutation testcase pretty easily, I would think.

Comment 5

[Jonathan Watt [:jwatt]]

This seems to just be down to the document order of elements. (Yuck!) I've reduced the attached testcase to a testcase that uses a <clipPath> containing a <use>. If the element referenced by the <use> comes after the <use>, I see the bug. If the element referenced by the <use> comes before the <use>, everything works fine.

Comment 6

[Jonathan Watt [:jwatt]]

Attachment: Testcase with <rect> after referencing <use> (broken)

Comment 7

[Jonathan Watt [:jwatt]]

Attachment: Testcase with <rect> before referencing <use> (works)

Comment 8

[Robert Longson [:longsonr]]

Roc's work on ID matching should fix it in that case. What we have basically is that the document draws without the reference being resolved and then when the reference is resolvable it doesn't cause an update as it should.

Comment 9

[Boris Zbarsky [:bzbarsky]]

> This seems to just be down to the document order of elements.

Yeah.  Did I forget to say that when I attached the testcase?  :(

And yeah, roc's thing will fix this.  The reason it worked in Firefox 2 is that we never started painting SVG until it was all loaded.

Which means we should either take roc's id-matching on the 1.9 branch or disable incremental loading for SVG or something...  At least I think it would be good to not have timing issues like this.

Comment 10

[Jonathan Watt [:jwatt]]

Well I didn't understand "order" dependent from "timing or size" dependent, but all's good. I'd really like to see roc's id-matching patch on 1.9 if at all possible, especially since we worked so hard to fix the bugs that appeared with incremental XML support.

Comment 11

[Robert O'Callahan (:roc) (email my personal email if necessary)]

The id-matching patch could be backported to 1.9 if you take out the part where I refactor nsXULDocument a lot. I'll try to extract the patch and submit it for 1.9.1 today.

Comment 12

[Jesse Ruderman]

I'm guessing you mean 1.9.0.1 / Firefox 3.0.1.  Isn't that a pretty big change for a security-and-stability update?

Comment 13

[Robert O'Callahan (:roc) (email my personal email if necessary)]

I guess it is. I'm not sure what we should do about 1.9. Maybe we should turn off incremental loading for SVG documents.

Comment 14

[Robert Longson [:longsonr]]

Fixed by check-in for bug 344258