Editor font: do not embolden the Main Font if it's variable

[DeeJayLSP]

Fixes #110426

During #106217's writing I was unaware that if the editor's Main Font Bold was unset, it would take the Main Font and embolden it.

In that situation, the weight would be set to bold and the embolden process would happen at the same time, resulting in a very heavy and blurry font.

This changes so emboldening won't happen if the font is variable, as by default, the bold font will be set to have a bold weight.

• Inter Variable set on both Main Font and Main Font Bold:

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• Inter Variable set on Main Font, Main Font Bold unset, before fix:

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• Inter Variable set on Main Font, Main Font Bold unset, after fix:

[Maran23]

Can confirm that this fixes the issue!

Fix makes sense.
I wondered what the magic number 2003265652 stood for. It turns out that it refers to the weight. I wonder if we should create a constant with a good name for it. Let's see what the folks at Godot have to say about it. :)

[Maran23]

Can confirm that this still works.

In the code, I saw also calls looking like this name_to_tag("weight"). Is there a difference between "wght"?

[DeeJayLSP]

In the code, I saw also calls looking like this name_to_tag("weight"). Is there a difference between "wght"?

From what I've seen in the code, name_to_tag() is supposed to work with four character OpenType tags, discarding the rest.

Whether those are wrong or not, that's unrelated to this PR and probably a case for another PR or issue.

Edit: I have been corrected in the comment below.

[bruvzg]

name_to_tag works with 4 letter string codes and a set of default names (see https://github.com/godotengine/godot/blob/master/modules%2Ftext_server_adv%2Ftext_server_adv.cpp#L536). The returned tag is uint32_t (contains the same 4 ASCII letter code in memory).

[Calinou]

Code looks good to me.