361523 - [Cairo / Cocoa] All borders not at pixel boundaries are a pixel too thick

Status: RESOLVED FIXED

(Core :: Graphics, defect)

Description

[Håkan Waara]

After the switch to cairo, the inset on form controls' borders are extremely thick.

Screenshots coming up.

Comment 1

[Håkan Waara]

Attachment: Before

Before the cairo-switch.

Comment 2

[Håkan Waara]

Attachment: After

Note that all form controls (buttons, textfields, select menus) have almost doubled their border's thickness.

Comment 3

[Jesse Ruderman]

Radio buttons look better, though.  http://quotes.burntelectrons.org/1594

Comment 4

[Wayne Woods]

What date was the switch to Cairo? I'm having trouble finding out on Bonsai or Bugzilla.

Comment 5

[Wayne Woods]

(In reply to comment #4)
> What date was the switch to Cairo? I'm having trouble finding out on Bonsai or
> Bugzilla.

Sorry, never mind. I don't know how I missed bug 323934, checked in 2006-11-21 16:58.

Comment 6

[Phil Ringnalda (:philor)]

*** Bug 363686 has been marked as a duplicate of this bug. ***

Comment 7

[David Baron :dbaron: (⌚️UTC-4, no longer working on Mozilla)]

What's going on here seems like a cairo bug.  Any border that's not aligned to a pixel boundary is getting drawn a pixel too thick.  It's nothing specific to form controls.  I'll attach a testcase to show this.

(It's probably showing up more reliably for vertical borders presumably because vertical coordinates are much more cumulative, and therefore much less likely to be pixel-aligned.)

Comment 8

[David Baron :dbaron: (⌚️UTC-4, no longer working on Mozilla)]

Attachment: testcase (all borders should be 2px wide)

All the borders in this testcase should be 2px wide, but only 1 out of every 10 is; the rest (not aligned to pixel boundaries) are 3px wide.

Comment 9

[Jesse Ruderman]

It this bug also responsible for making some link underlines appear too close to the link text?  Or is that a separate bug?

Comment 10

[David Baron :dbaron: (⌚️UTC-4, no longer working on Mozilla)]

Separate.  Underlines aren't done using FillPolygon, and I think the cause of this bug is a rounding bug in FillPolygon.

Comment 11

[Masayuki Nakano [:masayuki] (he/him)(JST, +0900)]

see bug 365336 for the underline problem.

Comment 12

[Vladimir Vukicevic [:vlad] [:vladv] (needinfo me, slow to respond)]

This should be fixed by the patch for bug 368247.