Summary:
Update the MathJaxFonts `Dockerfile` to enable the use of
`ttfautohint` which hints our fonts better. Also, fix the location that
batik is downloaded from, update some formatting in the `Dockerfile`,
and update the fonts and metrics.
Test Plan:
- Compare a rendered `= - A z 4 \Longrightarrow \Sigma \Biggl(` in
Chrome on Windows at font sizes 10px to 20px before and after this
change.
- See that characters look about the same, or better.
- See that the screenshot tests didn't change in firefox (maybe firefox
runs the same autohinting algorithm that we do?), and don't visually
change in chrome
Reviewers: kevinb, alpert
Reviewed By: kevinb, alpert
Differential Revision: https://phabricator.khanacademy.org/D18977
Since the Selenium images are available for download, and downloading them
is usually faster than building them from scratch, this makes taking
screenshots easier. Furthermore, since the Selenium image is not specific
to KaTeX, it could as well be used for other purposes, thus saving space
since a single image can be used in multiple projects.
This change also deals with the non-determinism in the Lap screenshot:
We detect the one known (and accepted) alternate rendering and change the
output file name to Lap_alt in this case. So either Lap or Lap_alt gets
saved to, and if the image is different from both, then one of these files
will show a modification. On the other hand, if it is equal to either of
these, then the matching one will get overwritten, showing no change.
A fraction is surrounded by a box of width \nulldelimiterspace on either side.
That size is 1.2pt and does not scale with the style or font size.
Furthermore, a \frac creates a brace-enclosed group which results in a
\mathord, not a \mathinner.
This commit introduces environments, and implements the parser
infrastructure to handle them, even including arguments after the
“\begin{name}” construct. It also offers a way to turn array-like data
structures, i.e. delimited by “&” and “\\”, into nested arrays of groups.
Environments are essentially functions which call back to the parser to
parse their body. It is their responsibility to stop at the next “\end”,
while the parser takes care of verifing that the names match between
“\begin” and “\end”. The environment has to return a ParseResult, to
provide the position that goes with the resulting node.
One application of this is the “array” environment. So far, it supports
column alignment, but no column separators, and no multi-column shorthands
using “*{…}”. Building on the same infrastructure, there are “matrix”,
“pmatrix”, “bmatrix”, “vmatrix” and “Vmatrix” environments. Internally
these are just “\left..\right” wrapped around an array with no margins at
its ends. Spacing for arrays and matrices was derived from the LaTeX
sources, and comments indicate the appropriate references.
Now we have hard-wired breaks in parseExpression, to always break on “}”,
“\end”, “\right”, “&”, “\\” and “\cr”. This means that these symbols are
never PART of an expression, at least not without some nesting. They may
follow AFTER an expression, and the caller of parseExpression should be
expecting them. The implicit groups for sizing or styling don't care what
ended the expression, which is all right for them. We still have support
for breakOnToken, but now it is only used for “]” since that MAY be used to
terminate an optional argument, but otherwise it's an ordinary symbol.
Summary:
Use the TeX definitions of `\root` to get the optional `\sqrt`
argument in the right place. Also add the MathML version.
Fixes#48
Test Plan:
- `make test`
- See that the images look good
Reviewers: kevinb, alpert
Reviewed By: alpert
Differential Revision: https://phabricator.khanacademy.org/D17236
Summary:
Using \phantom with non-phantom math in Perseus doesn't render to be the
same size because \phantom uses MathJax and the non-phantom math uses KaTeX.
Implementing \phantom in KaTeX should solve this alignment issue.
Test Plan:
[x] write (and run) unit tests
[x] create (and run) screenshotter tests
Reviewers: emily
Reviewed By: emily
Differential Revision: https://phabricator.khanacademy.org/D16720
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
