We now compute the cap-height from the rasterized glyph data.
Moved the scaling action of use_cap_height_to_scale_fallback_fonts from
glyphcache into the font resolver: when enabled, and we have data
about the baseline font and the font being resolved, then the resolving
font will be scaled such that the cap-height of both fonts has the same
pixel size.
The effect of this is that `I` glyphs from both fonts should appear to
have the same height.
Added a row of `I`'s in differing styles at the bottom of styles.txt
to make this easier to visualize.
refs: #1189
With this configuration:
```lua
local wezterm = require 'wezterm'
return {
font_dirs = {"/Users/wez/Downloads/Inconsolata"},
font = wezterm.font("Inconsolata"),
font_locator = "ConfigDirsOnly"
}
```
wezterm is now able to see the 74 variations that are available
in the single inconsolata ttf.
Running `WEZTERM_LOG=wezterm_font=trace wezterm` will log the
variations.
refs: https://github.com/wez/wezterm/issues/655
This is primarily for macos where the default freetype
installation is unable to render color emoji, but should also
help make things more consistent across the various platforms.
It's a little bit awkward on linux because the font-loader crate
pulls in the now-conflicting servo-font* crates. I've disabled
font-loader on linux systems; it's just calling fontconfig under
the covers anyway.
