Arabic/Western glyph sizes

[sp0rk]

Hello all,

I have recently been provided with two fonts - one which contains just Arabic glyphs, the other just Latin / Greek / Cyrillic. My client wishes for both fonts to be merged into one. I have had some success by adding the Latin etc. glyphs to the Arabic font, but the Latin glyphs now appear at almost half their original size. I think this is down to the difference in the points per em setting in each font (the Arabic font is 2048, the Latin 1000) but this is an area I'm not too familiar with - I've only ever designed my own fonts in the Latin range, never merged two fonts together, so I want to know the best way of adjusting the Latin font so that it appears at the correct size when merged into the Arabic font.

thanks!

[Bhikkhu Pesala]

Please see this tutorial thread:

Resizing fonts and Changing Units per Em Values.

Probably, what you want to match are Caps Heights. Hinting won't be preserved, but can be added again on export if you're using a recent version of FontCreator. Composites will need to be recomposed and adjusted.

2048 funits / em is good for most fonts. 1000 is a legacy from fonts created for the MAC.

[sp0rk]

Hi Bhikkhu

Thank you - that's very useful. I have succeeded in increasing the size of the Latin set following your instructions, but there appears to be some clipping at the top on accented capital letter glyphs. I guess it's because these glyphs are now taller than 2048 units but are the correct size in comparison to the Arabic glyphs. I don't want to touch the Arabic glyphs because of all the associated OT information :/

Currently the x-height is at ~1700, CapHeight at 2370 and WinAscent at 2700, WinDescent at -1319. I am not sure how changing these values really affects things, however.

thanks!

[Bhikkhu Pesala]

You don't need to change any metrics in the Latin font. Just copy/paste the glyphs to the Arabic font, and if the glyphs are not the right size, adjust the values used to modify the Latin glyphs and try again.

WinAscent/Descent metrics should be recalculated in Font Properties metrics maximum to avoid clipping. The Caps Height and x-height metrics are used to position diacritics with Complete Composites. These values are calculated from the top of H caps, and lowercase x respectively.

Font Metrics

Font Metrics.png (64.14 KiB) Viewed 6177 times

[Bhikkhu Pesala]

Looking at the Arabic glyphs in Times New Roman, it looks like you need to match the x-height to the Arabic glyphs, but I don't know Arabic. Select some Arabic glyphs and some Latin glyphs in the glyph overview, then press the P shortcut to compare them in the preview toolbar or use the Comparison Toolbar in the Glyph Edit window.

Times New Roman Arabic.png (5.22 KiB) Viewed 6176 times

[sp0rk]

Hi Bhikkhu

Thank you - I am getting there now. I think I have something missing though, as I can't see the Additional Metrics (x-height / Cap Height) settings in the UI, just the top box for Spacing.

[Bhikkhu Pesala]

On the Font Properties, General Tab, set the Contents and Layout to Version 3 or higher

[sp0rk]

Hi Bhikkhu

Thank you - whether I select Version 3 or 4 I still don't see the Additional Metrics box (FCP 8.0). Having had a search about for this, I think I need the update mentioned here: viewtopic.php?f=3&t=5112

[Bhikkhu Pesala]

Yes, you will need that update. Send an email to Erwin if he doesn't spot your post soon.

[sp0rk]

Thanks Bhikkhu - I have sent him a PM - I hope he got it, it says it's in my Outbox rather than Sent Messages