Fix width metric extraction #42
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Fix @ylemkimon's issues reported in KaTeX#41 (comment)
| width = glyph.xMax - glyph.xMin | ||
| height = glyph.yMax / unitsPerEm | ||
| depth = -glyph.yMin / unitsPerEm | ||
| width = widths[name].width / unitsPerEm |
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You can get width by glyph.width.
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No, I tried that, and it wasn't defined. Unless I somehow have the wrong version installed? I did it pretty recently.
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@edemaine Ah, sorry, I was looking at the fontforge Python API.
| depth = -glyph.yMin | ||
| width = glyph.xMax - glyph.xMin | ||
| height = glyph.yMax / unitsPerEm | ||
| depth = -glyph.yMin / unitsPerEm |
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During refactoring the generation scripts of fonts and their metrics, I discovered that yMax and yMin from generated TTF does not match height and depth from tfm(TeX font metrics).
Are their definitions different? Or, do they change during conversion process? If so, which metrics should KaTeX use?
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I just did some spot checking of Typewriter-Regular (as that's what I was working on recently) and the letters I checked seemed close, but there's definitely some error. For example, y has a yMin of -228 and yMax of 431, and the metrics file says [0.22222, 0.43056, ...]. That's more than floating-point rounding should account for... I'll turn this into an issue (#43).
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@ylemkimon the height and depth calculations look reasonable.
@edemaine the difference may be due to when we're getting the measurements. One of the steps in the pipeline is the darken the fonts by making them a bit thicker.
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It looks like only the entries that had issues in fontMetricsData.js were updated. Based on what I'm seeing in this diff things look fine. If there's differences between the TTF and tfm file it's probably because of the darkening we do the font.
Me neither. |
Fix KaTeX#1255 via KaTeX/katex-fonts#41. Also fix width metrics via KaTeX/katex-fonts#42.
* Fix space width in \texttt Fix #1255 via KaTeX/katex-fonts#41. Also fix width metrics via KaTeX/katex-fonts#42. * Improve test * Update screenshots
* Fix space width in \texttt Fix KaTeX#1255 via KaTeX/katex-fonts#41. Also fix width metrics via KaTeX/katex-fonts#42. * Improve test * Update screenshots
* Expose defineSymbol in the main KaTeX object * More Unicode letters (#1260) This PR serves as a complement to PR #1232 by supporting some letters that are omitted from the Unicode range 1D400–1D7FF. * Include Bold-Italic fonts for \boldsymbol (#1257) * Include Bold-Italic fonts for \boldsymbol Fix #1228 * Update screenshots * README: Add size badge (#1253) * README: Add size badge Add a size badge showing size of gzipped katex.min.js * update-sri: Add code to replace size badge in readme * Change to use badge from shields.io instead My bad for assuming that badgesize.io supports https. Change to use the badge from shields.io which supports https. * More Unicode letters (#1260) This PR serves as a complement to PR #1232 by supporting some letters that are omitted from the Unicode range 1D400–1D7FF. * Include Bold-Italic fonts for \boldsymbol (#1257) * Include Bold-Italic fonts for \boldsymbol Fix #1228 * Update screenshots * README: Add size badge Add a size badge showing size of gzipped katex.min.js * update-sri: Add code to replace size badge in readme * Change to use badge from shields.io instead My bad for assuming that badgesize.io supports https. Change to use the badge from shields.io which supports https. * Use badgesize.io with https * Fix space width in \texttt (#1261) * Fix space width in \texttt Fix #1255 via KaTeX/katex-fonts#41. Also fix width metrics via KaTeX/katex-fonts#42. * Improve test * Update screenshots
Fix @ylemkimon's issues reported in #41 (comment)
In particular, fix width of space characters.
I'm not an expert in fonttools but it seemed that I needed to use both the existing
'glyf'structure for xMin/xMax and thegetGlyphSetstructure for width. Let me know if you know a cleaner way.This will require rerunning the script if #41 gets merged first.