1667192 - Support loading hyphenation data from uncompiled .dic files as well as compiled .hyf tables

Status: RESOLVED FIXED

(Core :: Layout: Text and Fonts, enhancement)

Description

[Jonathan Kew [:jfkthame]]

See https://github.com/mozilla-mobile/fenix/issues/7223.

The precompiled binary .hyf files used by the mapped_hyph library are substantially larger than the original .dic pattern files from which they are derived (although using them involves a greatly reduced runtime memory footprint). This led to a 1.5MB increase in the Android APK size (as well as increased package sizes for desktop products, but this is much less significant).

To mitigate the APK size increase on Android, we could consider shipping the hyphenation data in the original uncompiled form, and compiling the binary table at runtime when a given dictionary is loaded.

This would give us a reduced APK download size and on-disk footprint, but the trade-off is that there will be a cost to page-load or reflow time on the first occasion hyphenation is requested for any given language (within the browser session).

Once loaded, the compiled table will be cached in shared memory for all content processes to use, so only the initial load of the first page to require hyphenation will be impacted. This may be worth accepting for the sake of reducing the package size.

Comment 1

[Jonathan Kew [:jfkthame]]

Attachment: Bug 1667192 - patch 1 - Update to mapped_hyph v0.4.0, to get FFI access to hyphenation table compilation. r=heycam

Comment 2

[Jonathan Kew [:jfkthame]]

Attachment: Bug 1667192 - patch 1.1 - Run `mach vendor rust` to update in-tree mapped_hyph source. r=heycam

Depends on D91408

Comment 3

[Jonathan Kew [:jfkthame]]

Attachment: Bug 1667192 - patch 2 - Update nsHyphenator to support loading either precompiled or uncompiled data. r=heycam

Depends on D91409

Comment 4

[Jonathan Kew [:jfkthame]]

Attachment: Bug 1667192 - patch 3 - For Android, package the uncompiled versions of hyphenation files. r=heycam

This reduces the APK size by about 1.4MB.

Depends on D91410

Comment 5

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/66b86f8b6682
patch 1 - Update to mapped_hyph v0.4.0, to get FFI access to hyphenation table compilation. r=heycam
https://hg.mozilla.org/integration/autoland/rev/a1ab26abf3eb
patch 1.1 - Run `mach vendor rust` to update in-tree mapped_hyph source. r=heycam
https://hg.mozilla.org/integration/autoland/rev/c29703edd736
patch 2 - Update nsHyphenator to support loading either precompiled or uncompiled data. r=heycam
https://hg.mozilla.org/integration/autoland/rev/ad5cf7320076
patch 3 - For Android, package the uncompiled versions of hyphenation files. r=heycam

Comment 6

[Cristian Brindusan [:cbrindusan]]

https://hg.mozilla.org/mozilla-central/rev/66b86f8b6682
https://hg.mozilla.org/mozilla-central/rev/a1ab26abf3eb
https://hg.mozilla.org/mozilla-central/rev/c29703edd736
https://hg.mozilla.org/mozilla-central/rev/ad5cf7320076