Combining character issues - U+0E1B, U+0E49

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Combining character issues - U+0E1B, U+0E49 #940

Open jubby2 opened 2 years ago

jubby2 commented 2 years ago

We have noticed a stacking problem in Angsana UPC when combining U+0E1B and U+0E49.

Other fonts, such as Adobe Thai, combine these characters properly: good character Adobe Thai

Is this something that can be resolved? Our corporation has 50 licenses through Fonts.com for use in InDesign, and it is our preferred font for Thai language products.

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Document Details

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ID: d2a92229-f3a6-585f-326b-e06a5e02c341
Version Independent ID: 60088004-f114-e8f8-8bd8-325a0d9e8b83
Content: AngsanaUPC font family - Typography
Content Source: typographydocs/font-list/angsanaupc.md
Product: typography
GitHub Login: @alib-ms
Microsoft Alias: alib

alib-ms commented 2 years ago

Thank you for letting us know. I will get the Angsana, Cordia and other fonts updated.

PeterCon commented 2 years ago

We have noticed a stacking problem in Angsana UPC...

This is a matter of preference. Above marks in Thai divide into two groups in relation to interaction with ascending stems:

some (e.g. U+0E34 sara i, U+0E47 mai tai khu) always shift to the left to avoid collision with an ascending stem
some, including U+0E31 mai han akat and U+0E49 mai thoo, have a stroke that overhangs to the right, and often overstrikes an ascending stem, though in some typography may be shifted to avoid the overstrike.

There are plenty of examples of the overstrike to be found in Thai lettering and printing tradition. The following is from a Thai book on lettering:

The following is an example from the same book of hand lettering in which these marks overstrike not just the ascender of the current base letter but even two or three letters away:

tiroj commented 2 years ago

There are plenty of examples of the overstrike to be found in Thai lettering and printing tradition.

Yes, but it needs to be done with some care, especially when various weights of stroke are involved. It is seldom visually adequate to slap the combining mark on top of the ascender stroke as in Angsana. If the mark is going to interact with the ascender, we usually make this a ligature so that we can refine the length and weight of the stroke of the mark where it intersects the ascender. The mark may often not cut all the way across the ascender. This is Adobe Thai:

alib-ms commented 2 years ago

Reviewing other fonts.

alib-ms commented 2 years ago