Bug 31640 – [CAIRO] Fails to paint solid outlines

• Component: Layout and Rendering
• Status: RESOLVED INVALID

[Gustavo Noronha (kov)]

Summary says it all. I was able to track this down to a Cairo xlib backend bug, in fact, but we may want to work this around somehow. See: https://bugs.freedesktop.org/show_bug.cgi?id=25167

Commenting this line in GraphicsContextCairo.cpp::drawConvexPolygon makes it work:

cairo_set_antialias(cr, shouldAntialias ? CAIRO_ANTIALIAS_DEFAULT : CAIRO_ANTIALIAS_NONE);

I am not sure win32 cairo suffers from this. I would bet not.

[Gustavo Noronha (kov)]

Created attachment 43450 [details]
test case

[Gustavo Noronha (kov)]

Created attachment 43451 [details]
expected rendering

[Benjamin Otte]

It works here, but I'm not exactly on master here.
What cairo version is that?
And your rendering is just the same only without the big black box?

[Dirk Schulze]

Also works for me. Cairo 1.8.8 here.

[Gustavo Noronha (kov)]

(In reply to comment #3)
> It works here, but I'm not exactly on master here.
> What cairo version is that?

1.9.2. I have now tried with 1.9.4, and 1.8.8 with the same problem. May be related to my version of X, perhaps, or of pixman?

> And your rendering is just the same only without the big black box?

Exactly.

[Gustavo Noronha (kov)]

Interestingly, the problem does not happen when I run GtkLauncher inside Xephyr, so hrm.

[Martin Robinson]

Are you still seeing this issue?

[Gustavo Noronha (kov)]

(In reply to comment #7)
> Are you still seeing this issue?

No, might have been fixed by an X/cairo upgrade, so I'll close it =)