Typo Ascender value is too low.

Anutrix commented 5 years ago

Typo Ascender values is too less which cause issues when used on single line things like buttons. HHead ascender values seem to be more appropriate. Simple test:

<!DOCTYPE html>
<html>
<head>
<link href='https://fonts.googleapis.com/css?family=Overpass:semibold' rel='stylesheet'>
<style>
button {
  background-color: #4CAF50; /* Green */
  border: none;
  font-family: 'Overpass';
  color: white;
  padding: 0px 0px;
  font-size: 60px;
}
</style>
</head>
<body>
 <button type="button">Click Me!</button> 
</body>
</html>

Firefox_Screenshot_2019-07-05T15-31-30 006Z Notice that the space below it is almost double than above. Having issues in other softwares using FreeType since it respects Typo flag since FreeType version 2.10.0. Another case: https://github.com/godotengine/godot/issues/28335

joemaro commented 5 years ago

when i use the font on my desktop on GTK and QT apps, the same happens: lots of space below the font and crammed towards the top.

rprpx commented 5 years ago

I experience the issue as well.
I'm in Manjaro Gnome Linux 18.0.4 With FreeType2 2.10.0 and 2.10.1 this issue is present with the Overpass font. The font "sits high" and so, for example, bumps the upper edge of buttons, etc. It doesn't look good at all. I'm really hopeful that someone might be willing to look after a fix. (My knowledge of font matters is far from sufficient for me to currently try to address the issue.)

(If I downgrade to FreeType2 2.9 the Overpass font issue does not appear, but this is an unacceptable "resolution" naturally since software dependency issues are bound to happen. For example, with this downgrade, FireFox 68 (at least) won't run for me.)

Some possibly helpful comments and information might be found at these links: 1) Link 1 2) Link 2 3) Link 3

I'm not familiar enough personally with font creation and such to truly understand the details provided in and around these linked comments, but I assume someone more knowledgeable with the subject might find them useful in fixing Overpass.

Thank you.

gforrest-bw commented 5 years ago

Related to #56?

madig commented 4 years ago

This might be text rendering stacks not dealing with typo metrics correctly, now that FreeType choses them if the UseTypoMetrics flag is on. Going from https://github.com/RedHatBrand/Overpass/issues/72#issuecomment-545753204, the typo line heights are likely correct, but Qt/GTK/Cairo do not properly add the line gap. Try increasing the line gap yourself.

Anutrix commented 4 years ago

@madig But the issue is not exactly about line gap, since the only issue is Typo Ascender value. Afaik, all 3 Ascender/Decender shouldn't have too much differences. I am still learning so I might be wrong, so do correct me if I am.

madig commented 4 years ago

Commonly, typo metrics are going to be tighter than the other metrics and that is on purpose. They are supposed to be used by typography-savvy applications to provide precise control over line height. Typo metrics come with some semantics attached (https://docs.microsoft.com/en-us/typography/opentype/spec/recom#tad) and require special handling by applications. AFAIK, no popular toolkit on Unixoids is doing that. The result is very tight line spacing.

Unfortunately, handling of line spacing across applications and operating systems differs significantly and it is more or less impossible to get the same metrics everywhere. Some strategies are explained in https://glyphsapp.com/tutorials/vertical-metrics. Google Fonts is pushing for the therein mentioned webfont strategy iirc, which assigns the same metrics to all fields. Maybe that helps for this font.

davelab6 commented 1 year ago

Does this family comply with the gf vm spec?

thlinard commented 3 days ago

Duplicated in #91

RedHatOfficial / Overpass

Typo Ascender value is too low. #72