http://bugs.winehq.org/show_bug.cgi?id=19082
--- Comment #12 from Jaime Rave jaimerave@gmail.com 2009-09-03 23:13:26 --- (In reply to comment #11)
Wine uses width 0 instead of 1 because it's faster. Still from your post it's clear that this is a driver dependent behaviour.
--- snip --- So, according to what I can read of the X protocol specification, neither the vesa nor intel drivers have a bug here. They are allowed to differ in these details of which pixels get lit. (And if anything, vesa is the odd one for not matching the algorithm of line_width=1.)
So, to fix the bug, wine is going to have to change its code to not rely on the pixelization of zero-width lines, (which can differ from one driver to the next), and should instead use lines with width=1. Making this change will require making some adjustments to how the segment endpoint coordinates are computed to still achieve the desired result. --- snip ---