718394 - Incorrect rendering of www.lebonforfait.fr

Status: RESOLVED FIXED

(Core :: General, defect)

Description

[Mathieu Marquer]

User Agent: Mozilla/5.0 (Windows NT 5.1; rv:12.0a1) Gecko/20120113 Firefox/12.0a1
Build ID: 20120113031050

Steps to reproduce:

1. Go on http://www.lebonforfait.fr/
2. Clic on "comparateur" on the top menu


Actual results:

Most of the page is not displayed. Some components will appear on mouseover. If you change tab then go back on lebonforfait tab, the page displayed won't changed (i.e. still displaying the content of the previous tab)


Expected results:

Correct rendering and behavior of the page.

Comment 1

[Boris Zbarsky [:bzbarsky]]

Seems to work fine on Mac, in a Jan 16 nightly.

Mathieu, does turning off hardware acceleration and restarting the browser help?

Comment 2

[Matthias Versen [:Matti]]

looks ok with  Mozilla/5.0 (Windows NT 6.1; rv:12.0a1) Gecko/20120114 Firefox/12.0a1 SeaMonkey/2.9a1

Comment 3

[Mathieu Marquer]

Even after updating to Mozilla/5.0 (Windows NT 5.1; rv:12.0a1) Gecko/20120116 Firefox/12.0a1 the bug is still there with hardware acceleration off through Nightly options and restarting the browser. 

No rendering issue with IE8, Chrome 18.0.1003.1 dev-m, Firefox 9.0.1 on the same computer. This computer is running Windows XP SP3 with Intel GMA 4500MHD graphics chip.

I will try tonight (CET time) on a Linux platform.

Comment 4

[Mathieu Marquer]

Well, also occurs on Mozilla/5.0 (X11; Linux x86_64; rv:12.0a1) Gecko/20120115 Firefox/12.0a1 (running nVidia proprietary drivers), even with hardware acceleration desactivated. The only page with a rendering issue is http://www.lebonforfait.fr/comparateur.html (screenshot attached, the elements shown only appeared after putting the mouse cursor "blindly" over it), the rest of the website works fine.

Comment 5

[Mathieu Marquer]

Attachment: Screenshot of the rendering issue on a Linux platform

Comment 6

[Boris Zbarsky [:bzbarsky]]

That's really bizarre.  Esp. the part about happening on Linux and Windows but not Mac...

Comment 7

[Timothy Nikkel (:tnikkel)]

This is interesting, sometimes it doesn't draw anything at all (still shows the old page) when you switch to that tab, sometimes it works just fine for me.

Comment 8

[Timothy Nikkel (:tnikkel)]

We hit _cairo_error with status=CAIRO_STATUS_INVALID_MATRIX from

_cairo_gstate_set_matrix
_moz_cairo_set_matrix
gfxContext::SetMatrix
mozilla::layers::BasicLayerManager::PaintLayer

where the matrix is

{
  xx = 0, 
  yx = 0, 
  xy = 0, 
  yy = 0.017064847052097321, 
  x0 = 903, 
  y0 = 431
}

Comment 9

[Timothy Nikkel (:tnikkel)]

The first bad revision is:
changeset:   79230:8b89d7037306
user:        Matt Woodrow <[e-mail]>
date:        Wed Oct 26 16:24:58 2011 +1300
summary:     Bug 695275 - Fix conversion of ThebesLayers to ImageLayers. r=roc

Comment 10

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

Need to avoid setting a singular transform in that code, I guess.

Comment 11

[Maxime Quandalle]

Hi,

I'm Max the creator of lebonforfait.fr
The bug is still there in the latest public build of firefox (v10). So many users can't access to the "comparateur.html" webpage.

Do you have any idea of what I should change in order to correct that ?

Comment 12

[Timothy Nikkel (:tnikkel)]

Does the page use CSS transforms? Can you produce a reduced version of the page that has the same problem? That would make it easier to see what is happening exactly, to know what could be changed.

Comment 13

[Maxime Quandalle]

The page does not use CSS transforms.

OK, I'm working on it.

Comment 14

[Timothy Nikkel (:tnikkel)]

Or a testcase that is reasonably self contained, an html file and a couple of js/css files. Something that I can poke at more easily.

Comment 15

[Maxime Quandalle]

I think I identify the source file of the bug : http://lebonforfait.fr/scripts/slider.js (when I disabled this file, it works well)

This js file is a third party part named BlueShoes. The project is here : http://www.blueshoes.org/en/javascript/slider/

Comment 16

[Timothy Nikkel (:tnikkel)]

Yeah, the problem seemed to be with an image that was part of the slider. So disabling the slider completely would fix it, but doesn't give any insight into what exactly is causing the problem.

Is it possible to produce a standalone copy of that page (or version of that page that shows the same problem)? A zip containing the necessary files maybe? That would be much easier to dig into.

Comment 17

[Maxime Quandalle]

You're right, disabling the slider "correct" the display bug.

Here is a reduced page : http://lebonforfait.fr/testbugff.html

Comment 18

[Maxime Quandalle]

The bug seems to be solved.
I changed the _bsImages/slider.gif image from a 243*243px to a 1*1px. 

I don't know where this image is used, but changed this image has correct the bug!

Comment 19

[Timothy Nikkel (:tnikkel)]

That makes sense, a 1x1 image doesn't use this code path (it doesn't get a layer because it is below the lower limit for image size).

But we now don't have any way to reproduce this bug as your site is the only example. Is there anyway you can make available an example that shows the bug while still keeping your site working?

Comment 20

[Matt Woodrow (:mattwoodrow)]

Drawing errors because of a singular matrix should be fixed by bug 810302.