591316 - background-gradients are calculated incorrectly

Status: NEW

(Core :: Layout, defect)

Description

[matthias koplenig [:metasieben]]

User-Agent:       Mozilla/5.0 (X11; Linux i686; rv:2.0b5pre) Gecko/20100826 Minefield/4.0b5pre
Build Identifier: Mozilla/5.0 (X11; Linux i686; rv:2.0b5pre) Gecko/20100826 Minefield/4.0b5pre

using linear gradients as background on the body-element, however i'm seeing some unexpected results.

in all those tests my browser-window has an outerHeight of 900px

(1) http://serfer.at/bgtest.php
the content(centered white) block is 500px high. all lines align perfectly. the blue stripe is 80px and starts at 100px.

(2) http://serfer.at/bgtest.php?h=1500
the content(centered white) block is 1500px high. the background-gradient is shifted down 2px, the blue stripe is 81px




Reproducible: Always

Comment 1

[Boris Zbarsky [:bzbarsky]]

Hmm.  Yeah, that offset there is odd.  roc, dholbert any idea what's going on here?

Comment 2

[Daniel Holbert [:dholbert]]

Looks like a pixel-rounding issue of some sort.  Try zooming -- there are scroll levels that are aligned or misaligned, on both testcases. (Also, some levels have the blue bar's top aligned, but not its bottom.)

So #1 isn't necessarily any more "working" than #2 -- it's just lucky enough to be working at the default scroll-level. :)