opentypejs
Handling vertical advance; ascender / descender doesn't look correct for some fonts
Expected Behavior
I'm looking for the correct way to draw a font vertically.
Current Behavior
If I use font.ascender and font.descender to determine vertical placement (unitsPerEm taken into account), I get unnaturally large gaps between characters with vertical spacing.
This is odd, since opening the font in FontForge doesn't show such abnormally large ascender/descenders as I'm getting from opentype.js.
Maybe it has something to do with you reading the glyph data instead of the actual font metrics?
Possible Solution
I noticed FontForge has a concept of a vertical advance, which I don't see in opentype.js.
Steps to Reproduce (for bugs)
- Draw glyphs manually, using font.ascender and font.descender as metrics for spacing the glyphs vertically.
Your Environment
- Version used: 1.3.4
- Font used: Noto Sans JP
After inspecting the code, it seems the vmtx/vhea table is not parsed, and thus this feature is not supported. If it's easy enough I'll open a PR for it.
Version 1.3.4 is outdated and has been for several years now, we're preparing a new release, please try the in development version 2.0.0 on the master branch.
Master branch works the same, like I said parsing vmtx/vhea will be the solution to this problem.
Master branch works the same, like I said parsing vmtx/vhea will be the solution to this problem.
We'll look into it, probably for version 2.1.0 as we need to get 2.0.0 out quick.
I'm actually going to close this as it seems to be a duplicate of #618. I will post a link to this issue in #618 so we can reference it.
We'll look into it, probably for version 2.1.0 as we need to get 2.0.0 out quick.
This is a very simple change; parse some tables, expose a few variables. Doubt you're going to see anything controversial in the PR because it's basically the existing hmtx / hhea code copied and renamed.