Label3D alignment does not appear to be accurate

[RichMakeGame]

Tested versions

v4.2.stable.official [46dc277]

System information

Godot v4.2.stable - Windows 10.0.19045 - Vulkan (Forward+) - dedicated NVIDIA GeForce GTX 1650 (NVIDIA; 31.0.15.4633) - Intel(R) Core(TM) i3-10100 CPU @ 3.60GHz (8 Threads)

Issue description

I'm using label3D and need to use top/left alignment and have consistent placement when the font size changes, however the Left / Top alignment does not keep the top/left of the text plane in a consistent position. Similar issue is present with Right/Bottom. At default settings and font size of ~286 the text drifts -0.5 units in y

all these label3D items have the same transform, top/left alignment, just different font size:

Steps to reproduce

Add a label3d to a 3d project, write some text eg 'Test text'
set alignment to Left and Top, and snap view to front orthogonal
alter font size from 1 up to 350 and notice the alignment starts above left of the origin and strays right and quite far below

a similar problem occurs if set to Right and Bottom alignment

Minimal reproduction project (MRP)

3dlabel_align_issue.zip

[akien-mga]

CC @bruvzg

[bruvzg]

I do not think it's bug and not Label3D specific (the only Label3D specific part, it's showing bounding box of the visible part). The left edge of the T top line is not a left edge of the glyph, and text is aligned to the glyph edge (other apps do the same):

[RichMakeGame]

Ahaa ok I see, so it is actually scaling correctly its just I was confused by the bounding box?

[akien-mga]

Closing as this was apparently not a bug, but not #89145 should fix the bounding box to make it clearer.