Material Symbols/Icons don't seem to render correctly

[KenVanHoeylandt]

Problem

When converting Material Symbols (newest fonts) and Material Icons (older variants), the icons are smaller than expected, and they're also not vertically centered.

Examples

Material Symbols:

Material Icons:

Reference with properly converted AwesomeFont icons:

Material Symbols with debug rendering on LVGL:

Debug export with 14px size, with lv_font_conv:

Note that the icons are 12px high instead of 14px.

Debug data for the above character:
60029 debug.txt

Bounty

I'm putting a 50 EUR bounty on this. I am able to pay it via Paypal/OpenCollective/GitHub/European bank transfer. Payment is limited to these options, but I am open to discuss alternatives.
If you can prove that it's more work, I'm willing to raise the bounty.

Background

I want to add more icons to my open source project, but the AwesomeFont license doesn't seem to allow me to redistribute the icons in my GPL-licensed project.

[kisvegabor]

Hi,

the icons are smaller than expected, and they're also not vertically centered.

I think these are independent issues.

Size difference:
E.g. 2 fonts with 14px size doesn't have the same real size. I'm not typography expert, but ou can also check it yourselves. I've just picked some random fonts with 16pt size:

Centering issue:
Unfortunately LVGL doesn't support baseline alignment now. I suggest using lv_obj_set_style_translate_y(icon, 2, 0) (change 2 as needed) to offset the icons.

[KenVanHoeylandt]

It could be 2 separate issues, but it depends:
If the sizing issue is fixed, and the size increase makes it grow while anchored from the top-center or top-left, then it will also fix the centering issue.

My guess is that the starting (x,y) coordinates of the glyph are correct, but the rendering size of it is not.

edit/unrelated: Apparently the image I had for "Reference with properly converted AwesomeFont icons:" was incorrect, so I updated the issue.

[lukilukeskywalker]

ha! I am having the same issue!!!

The 2 upper icons are some converted icons with latest version of lv_font_conv avaliable in node.

I have a Makefile that fixes the icons I want to add (By converting svg strokes to fills), then creates a new font, and the newly created font gets converted to a C file with the lv_font_conv

Dockerfile.txt

Makefile.txt

The generated icon font seems to be shifted up and is not the same size as the other fonts

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