[3.x] Support multiline strings in buttons

[Waridley]

Added new String::split_lines and Font::get_multiline_string_size methods to make this and possible future features easier. Then I simply put the button text rendering logic in a for loop that loops over each line. Perhaps there's a more efficient method for rendering a block of text, but this changed as little code as possible, and I tried to make sure it was as efficient as I could.

Fixes #2967

[akien-mga]

@bruvzg is working on a complex overhaul of text rendering for Godot 4.0 #41100 that will conflict and supersede with these changes, so they're unlikely to be merged in master.

There might be a case for adding it to 3.2 though, that can be discussed further.

[rmasp98]

@bruvzg is working on a complex overhaul of text rendering for Godot 4.0 #41100 that will conflict and supersede with these changes, so they're unlikely to be merged in master.

There might be a case for adding it to 3.2 though, that can be discussed further.

This information really should have been supplied in the original issue so that people don't waste there time trying to fix something that is never going to get merged

[Calinou]

@rmasp98 This pull request could be redone from scratch for the 3.2 branch. In this case, it can probably be merged.

@Waridley If you have time, could you look into recreating this pull request based on the 3.2 branch? Thanks in advance 🙂

[Waridley]

Since I've been working with 3.2 anyway, I just switched this PR to the changes I've been working with.

[KoBeWi]

Actually I just noticed that this was for 3.x branch, sorry. The issue still exists in there.

[KoBeWi]

Tested and it works, code looks good overall (left some minor comments).

Needs a check from @bruvzg probably, for the String methods. I'm not sure about the \r thing.

[bruvzg]

Not sure about adding String::split_lines and Font::get_multiline_string_size for a single use. Otherwise, code looks fine.

[Waridley]

Not sure about adding String::split_lines and Font::get_multiline_string_size for a single use. Otherwise, code looks fine.

Would they potentially be worth exporting and documenting for users in GDScript? Or should I just inline them?

[akien-mga]

Do we even need split_lines? I'm not sure \r is supposed for line break in Godot strings and so split("\n") should be sufficient.

[Waridley]

Do we even need split_lines? I'm not sure \r is supposed for line break in Godot strings and so split("\n") should be sufficient.

You're right, looks like all the places that deal with '\r' are parsing external files, not Object properties.

[akien-mga]

Thanks!