2050224 - [skpdf] Emojis print blank.

Status: RESOLVED FIXED

(Core :: Printing: Output, defect, P3)

Description

[Emilio Cobos Álvarez [:emilio]]

The only real test failure from turning skpdf on on nightly, is a failure in the test added for bug 1723787.

STR:

• Enable skpdf.
• Go to https://wpt.live/css/printing/emoji-print.html
• Print to pdf.

ER:

• Emoji prints.

AR:

• Blank page.

I haven't dug further just yet.

Comment 1

[Lee Salzman [:lsalzman]]

Emilio, this seems to work for me fine on Linux. Are you on macOS, by chance?

Comment 2

[Emilio Cobos Álvarez [:emilio]]

No, I was on Linux, and so is the CI run FWIW. Curious, did you actually "Save as PDF" with print.experimental.skpdf=true.

Comment 3

[Lee Salzman [:lsalzman]]

I did toggle the pref, and on my nightly build it still works for me. On Debian Linux.

Comment 4

[Lee Salzman [:lsalzman]]

Attachment: test that emoji are not blank in print output.pdf

The resulting output pdf with skpdf=true pref on.

Comment 5

[Emilio Cobos Álvarez [:emilio]]

Ah, I think I found something. My default emoji font is a COLR font. Maybe yours isn't?

Comment 6

[Lee Salzman [:lsalzman]]

The inspector says Twemoji Mozilla.

Comment 7

[Emilio Cobos Álvarez [:emilio]]

Ah, for me it's Noto Color Emoji

Comment 8

[Emilio Cobos Álvarez [:emilio]]

Attachment: Bug 2050224 - Fix SkCairoFTTypeface::onGetUPEM(). r=lsalzman

Without this fix, we bail out in:

https://searchfox.org/firefox-main/rev/c1395f54bdda7cb0ed71bbe54e2940ce16175389/gfx/skia/skia/src/pdf/SkPDFFont.cpp#160-162

This matches Skia's SkTypeface_FreeType::GetUnitsPerEm (but without the
SkIntToScalar nonsense because the int->float->int conversion seems
just useless?).

Comment 9

[Pulsebot]

Pushed by [e-mail]:
https://github.com/mozilla-firefox/firefox/commit/68d141f64705
https://hg.mozilla.org/integration/autoland/rev/28de3fbd708b
Fix SkCairoFTTypeface::onGetUPEM(). r=lsalzman

Comment 10

[pstanciu]

https://hg.mozilla.org/mozilla-central/rev/28de3fbd708b