71523 - The frame's x,y location should be adjusted to fall on a pixel boundary

Status: RESOLVED INVALID

(Core :: Layout, defect, P1)

Description

[Kevin McCluskey (gone)]

In the process of converting from twips to pixel's we are sometimes off by one
pixel because of roundoff error. This results in calls to invalidate the frame's
rect which are sometimes 1 pixel too narrow. It may make sense to condition the
location of a frame so it's twip coordinates coorespond to pixel boundary.
The problem is the x,y coorindate may contain a twip value that is a fraction of
a pixel. When the width of the frame is added to the x coordinate the number of
pixels will vary depending on the x corrdinate's sub-pixel twip coordinate.

Comment 1

[Andreas Franke (gone)]

*** Bug 71524 has been marked as a duplicate of this bug. ***

Comment 2

[Jesse Ruderman]

This bug was split off of bug 63951 so that a hacky fix could be applied to 
that bug.

Comment 3

[Marc Attinasi]

Moving Mozilla 1.01 bugs to 'future' milestone with priority P1

I will be pulling bugs from 'future' milestones when scheduling later work.

Comment 4

[Boris Zbarsky [:bzbarsky]]

dup of the general bug on units?

Comment 5

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

No, but I disagree with the proposed solution. The real solution is for
Invalidate to round out the app-units-rect when converting to pixels.

Comment 6

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

therefore, marking INVALID