66573 - Weird single pixel offsets in various parts of the page

Status: RESOLVED WORKSFORME

(Core Graveyard :: GFX, defect)

Description

[Travis Ogdon]

From Bugzilla Helper:
User-Agent: Mozilla/5.0 (X11; U; Linux 2.2.18 i686; en-US; m18) Gecko/20010125
BuildID:    2001012509

When visiting some sites (I've noticed on Salon more than others) with today's
build some of the lines of pixels running horizontally are offset by one pixel
(in either direction). The previous and following lines of pixels are rendered
correctly.

Highlighting the line (if there's text on it or not) will fix the problem. 

I'll include two screengrabs in a second to demonstrate what I'm talking about.



Reproducible: Always
Steps to Reproduce:
To reproduce simply visit the linked page at Salon, or other pages with today's
build. The problem is subtle, so it may take a second to notice.

I'm using a Matrox g400 card with XFree86 4.02. I have not noticed this problem
in the past (I update to the lastest nightly build Monday-Friday).

Comment 1

[Travis Ogdon]

I just noticed that when scrolling (either with the mouse wheel or the cursor
keys) new lines get screwed up, so it's apparently related to scrolling somehow.

Comment 2

[Travis Ogdon]

Attachment: Example of the problem. Green dots used for emphasis.

Comment 3

[Travis Ogdon]

Attachment: Same page after selecting text. Green dots for emphasis.

Comment 4

[Travis Ogdon]

I tried various builds all the way back to .7 and I saw this bug in all of them,
so this has been around for a while. Hopefully I'm not duplicating an already
reported bug here... I couldn't find one about it at least.

Comment 5

[Keyser Sose]

Not seeing this on Windows, must be a Linux only bug. I will try it when I get
home later tonight. Nice to see someone knows where to read for there political
information too :)

Comment 6

[Keyser Sose]

WORKSFORME
Platform: PC
OS: Linux 2.2.16
Mozilla Build: 2001012706

Any more information that might help us reproduce it?

Comment 7

[Matthew Cline]

Worksforme on Linux 2001012806, i686, RedHat 6.1

Comment 8

[Travis Ogdon]

I'm not sure what's different with my setup, but I continue to see the problem.
This is definitely not present in Netscape 4.76. 

I'm probably reaching here, but maybe it's a bug with X. I'm running 4.02 on a
Matrox g400 max. I'm using Debian (woody), but the X install is from the binary
packages off of xfree86.org. 

Again, it's most noticable on Salon (for me), but I see it on this page too,
it's just more subtle. I can make it go away by scrolling or highlighting the
problem areas.

Comment 9

[Keyser Sose]

There has been some problems with >= X Windows 4.0 with truetype fonts. You
might want to search for some bugs on that see if you can resolve it by seeing
what the resolution to those are.

Comment 10

[R.K.Aa.]

not visible w nvidia/xfree86 3.3.16 and gnome.
However: I remember a similar problem that only appeared in NC4.75 when using
KDE. Lines of text got shifted midways, and were set half a pixel off (don't
remember if it was up or down). Like in this bug, selecting the text cured the
problem. Under Gnome i didn't see the bug.

Reporter: Which desktop environment/WM are you using?

Comment 11

[Travis Ogdon]

I'm using enlightenment. No Gnome or KDE bits. I've tried fiddling with the 
TrueType fonts, but I haven't seen any improvement. 

I really only see this a lot at salon, so perhaps it has something to do with 
the font they're using there in combination with the use of lots of tables.

I find it curious that I don't see the problem with Netscape 4.76, but I'm 
guessing it probably has something to do with 4.76's wonky font rendering.

Comment 12

[R.K.Aa.]

Which truetype server are you using? xfs/xfsft? (which in XFree86 v.4.* is
simply called "truetype")

I see from your screenshot that the bold version of Verdana isn't used. When i
load the page, i get bold verdana a few places you don't have it. 

One of the lines that should have had a bold font is the one where the little
page-image seems broken. If you confirm you use xfs, i have an idea i'd like you
to test.

Comment 13

[R.K.Aa.]

Sorry! xfs/xfsft is called FREETYPE in XFree86 v.4.* Is that what you use?

Comment 14

[Travis Ogdon]

I'm using the builtin TrueType font support in xfree86 4.

Comment 15

[Travis Ogdon]

Ok, nothing has changed on my system, but the problem has gone away. I saw it in
.8, but I'm not seeing it in either the 02/26 or 02/27 builds. I have no idea
what was fixed, but I can assure you that nothing has changed in terms of my
fonts, xserver, or otherwise...

Comment 16

[Chris Petersen]

Marking verified worksforme based on reporter's last comment.