Katex: Break in tall delimiters

[OisinMoran]

• [x] Check common issues.
• [x] Check the bug is reproducible in the demo. If not, check KaTeX is up-to-date and installed correctly.
• [x] Search for existing issues.

Describe the bug:
Left and right floor brackets, when containing a large expression, appear to to break in the middle. This disappears on zooming but makes for suboptimal rendering.

(La)TeX code:

5 = \left\lfloor{\sqrt{\sqrt{\sqrt{\sqrt{\sqrt{(4!)!}}}}}}\right\rfloor

Expected behavior:
Expected vertical bar portion of left and right floor braces to be continuous.

Screenshots:
Taken from the demo.

Environment (please complete the following information):

• KaTeX Version: 0.10.1
• Device: Desktop
• OS: Ubuntu 18.10
• Browser: Chrome
• Version: 74.0.3729.131 (Official Build) (64-bit)

[kevinbarabash]

We could probably use SVG to avoid this situation. @OisinMoran are you seeing similar issues with tall parens and tall square brackets?

[OisinMoran]

Yes, with

5 \ne \left[{\sqrt{\sqrt{\sqrt{\sqrt{\sqrt{(4!)!}}}}}}\right]

I get:

And with

5 \ne \left({\sqrt{\sqrt{\sqrt{\sqrt{\sqrt{(4!)!}}}}}}\right)

I get:

[kevinbarabash]

Thanks for confirming my suspicions.

[ronkok]

I think this can be fixed without SVG. We just need to adjust the vertical alignment calculation in makeStackedDelim(). That calculation should include a small overlap where glyphs meet. Otherwise floating point rounding error can result in the gap we see in @OisinMoran's screenshots.

I'll take a look sometime in the next week.