Closed Bug 519168 Opened 15 years ago Closed 15 years ago

Fix a few spurious reftest failures

Categories

(Core :: Layout, defect)

Product:
Core
Component:
Layout
Type:
defect
Priority:
Not set
Severity:
normal

Tracking

()

Status:
RESOLVED FIXED

People

(Reporter: roc, Assigned: roc)

Details

Attachments

(1 file, 1 obsolete file)

fix v2
5.48 KB, patch
dbaron
: review+
Details | Diff | Splinter Review
Attached patch fix (obsolete) — — Splinter Review 
box-properties/CSS21-t100301.xhtml fails on my Mac because of subpixel antialising issues; we get seams at the edges of the Ahem glyph boxes because they're drawn with independent cairo_show_glyphs calls. My patch works around this issue by not actually rendering the glyphs, instead we wrap the Ahem characters in a span and use the span's background to draw the color, which pixel-snaps and thereby avoids seam issues.

font-face/ahem-metrics-1.html has a similar issue with the Ahem glyph box not being pixel-snapped, and the fix is similar.

bugs/379316-2.html has a problem on Linux (for me) where using rgba with alpha=0.5 gets subpixel-AA on the text but using opacity:0.5 does not (which makes sense, we don't support temporary surfaces with one alpha channel per color channel). We can work around this by giving the <body> alpha=0.9 in test and reference, forcing subpixel-AA off in both cases whenever we don't support 6-channel temporary surfaces.
Attachment #403192 - Flags: review?(dbaron)
Attached patch fix v2 — — Splinter Review 
oops, forgot to qrefresh
Attachment #403192 - Attachment is obsolete: true
Attachment #403196 - Flags: review?(dbaron)
Attachment #403192 - Flags: review?(dbaron)
The opacity:0.9 changes look fine; r=dbaron on those.

I'm uncomfortable with the idea that we can't use Ahem for its intended use in reftests (and on Mac only, for only some Macs).  Is there anything else we can do about that?
No. We can't guarantee non-antialiased rasterization. With SVG Fonts we could create an SVG version of Ahem that we rasterize and can therefore guarantee pixel-alignment.
Comment on attachment 403196 [details] [diff] [review]
fix v2

>+        .X, .space { background:green; color:transparent; }

could you put this style on the :before pseudo-element?

Also, fix the indentation (probably by continuing to use tabs).

r=dbaron with that
Attachment #403196 - Flags: review?(dbaron) → review+
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