* Make accents zero width
Make the width of an accented character equal to the width of the character,
by making accents zero width. In particular, fixes#1028 (`\ddot\imath`).
This involved reworking all of the accent offset machinery, in particular
skew and accent-hungarian. A bit cleaner now.
Also added support for the new width character metrics in symbolNode.
* Update AccentsText test
* Fix comment
The previous code incorrectly implemented TeXbook rules. First off,
the font metrics at issue should be those for the superscript/
subscript style, not the main style. Secondly, the metrics should be
scaled by the font size.
This changes some screenshotter tests (and they look more like TeX
now).
The combination of jspngopt and pako should eliminate possible causes for
different PNG encodings, although the core reason for #325 remains unknown.
Pako has poorer compression rates than native libz, but optimization can
counter that effect, and actually reduce the size of the screenshots.
The screenshots for LimitControls and UnsupportedCmds on Firefox used to
exhibit subpixel rendering before, for reasons unknown. The regenerated
versions don't exhibit this. See #324 for a discussion.
Summary:
Create our own screenshotting script which takes screenshots. This
improves over huxley for a couple reasons:
- It makes the screenshots the correct size (for some reason, huxley struggles
with this).
- Its configuration matches more with what we want (we don't need multiple
screenshots or interaction, we just want a single static shot)
- It runs faster
I also changed the docs to reflect this change.
Test Plan:
- Make sure all of the tests that were in the Huxleyfile are now in ss_data.json
- Run the screenshotter docker
- Make sure all of the images look reasonable and don't change (except
sometimes the Lap test, which has some strange pixel-positioning
differences...)
Reviewers: kevinb
Reviewed By: kevinb
Differential Revision: https://phabricator.khanacademy.org/D16731
