Make hypertext[] respect font size settings

[grorp]

While testing #13850 on Android, I noticed that the text rendered by hypertext[] was larger than other text. hypertext[] has a hardcoded default font size of 16 and doesn't respect font_size and mono_font_size, which are set to 14 on Android by default.

Since modders can specify absolute font size values for hypertext[], just using the mentioned settings as default values instead isn't enough. What this PR does is this:

font_size = myround(font_size / 16.0f * g_fontengine->getFontSize(font_mode)); 

To do

This PR is a Ready for Review.

How to test

Set font_size to 10, set mono_font_size to 30. Execute /test_formspec in a Devtest world, go to the "Hypertext" tab and see that your font size settings are applied.

[SmallJoker]

A proper solution would be to use multipliers (e.g. 0 ... 5) to scale the font based on the client's settings. The API is marked as unstable in the docs, hence this behaviour could in theory be changed. However, I am sure several mods already rely on the fontsize property. If compatibility is desired, the formspec version could be used to differentiate between the two notations (absolute and new relative).

Opinions?

[grorp]

A proper solution would be to use fractions (e.g. 0 ... 5) to scale the font based on the client's settings. The API is marked as unstable in the docs, hence this behaviour could in theory be changed. However, I am sure several mods already rely on the fontsize property. If compatibility is desired, the formspec version could be used to differentiate between the two notations (absolute and new relative).

Opinions?

If I understand your proposal correctly, doesn't that just mean replacing the current 0...16 range with a 0...5 range?

[SmallJoker]

@grorp No, the proposed change is to have a multiplier (edited the comment accordingly) in place of the current absolute font size.

[grorp]

Added to milestone as written on IRC: https://irc.minetest.net/minetest-dev/2023-10-08#i_6120697

I think the approach of this PR is good enough, but I'd also be fine if someone implemented a different solution.

[srifqi]

This implementation looks fine to me.

[SmallJoker]

srifqi appears to use a noticeably bigger mono font size (setting value) to test this change. The hypertext element does look "more correct" when two similar or identical scales are chosen.
Works.

[srifqi]

srifqi appears to use a noticeably bigger mono font size (setting value) to test this change.

Correct. I used the values in the first post to test it.

How to test

Set font_size to 10, set mono_font_size to 30. Execute /test_formspec in a Devtest world, go to the "Hypertext" tab and see that your font size settings are applied.