Italic text alignment

[aplavin]

I noticed that adding italic text to the legend moves the text down a bit compared to regular font – notice that the 2nd entry has a larger padding at the top and a smaller padding at the bottom:

with_theme(theme_latexfonts()) do
	scatter(rand(10), label="Abc")
	scatter!(rand(10), label=rich(rich("Def", font=:italic), "Def"))
	scatter!(rand(10), label="Xyz")
	axislegend()
	current_figure()
end

The workaround I found for now is this:

let l = axislegend()
	# XXX: to fix italic text valign
	lab = content(l.grid[1,1][2,2])  # target label that has italic
	lab.padding[] = (0,0,0,-3)
	lab.tellheight[] = false
end

But would be great to align the text automatically so that both italic and regular fonts are consistent.

• what version of Makie are you running? (]st -m Makie) 0.21
• can you reproduce the bug with a fresh environment ? (]activate --temp; add Makie)
• What platform + GPU are you on? any

[jkrumbiegel]

That is not a bug, simply a consequence of the font metrics. You can see that the italic font has a much larger ascender than descender, so when vertically centered the visual result is not really centered.

I have actually made my own version of our default font TeX Gyre Heros because of this, I wanted good vertical centering so I adjusted the ascenders and descenders accordingly.

with_theme(theme_latexfonts()) do
    f = Figure(fontsize = 50)
    gl1 = GridLayout(f[1, 1], valign = :bottom)
    gl2 = GridLayout(f[1, 2], valign = :bottom)
    colgap!(f.layout, 0)
    Box(gl1[1, 1])
    Label(gl1[1, 1], "ABC", font = :italic)
    Box(gl2[1, 1])
    Label(gl2[1, 1], "ABC")
    f
end

[aplavin]

Thanks for the pointers! I'm not deeply familiar with fonts and their metrics, just looking for a nice workaround to get the uniform visual alignment (preferably without manually digging into legend/layout internals). Maybe a different default latex font then?

[jkrumbiegel]

Yes if you find a different font variant that would be the easiest solution.

[aplavin]

I wonder if a font-independent solution could work as well – for example, to constrain the rendered lineheight to be the same for all legend entries. Doesn't matter which one is chosen (probably the largest), just that it's consistent.