Still about:
http://www.keyboard-layout-editor.com/#/layouts/657a91653495a21fe551349c3ee89ba2
I made a diagram to verify that everything is covered. I am trying to be exhaustive here in order to not forget anything.
The basis for this exercise is the
Multilingual European Subset 1 (MES-1), which is a
standardized subset of Unicode which aims to cover all Latin-script languages used in Europe (which implies that North and South America are also covered if you don't consider obscure indigenous languages). MES-1 is the most recent version of a standardization process that goes back to
ISO/IEC 6937.
This is the list of languages covered by MES-1:
Afrikaans, Albanian, Basque, Breton, Catalan, Croatian, Czech, Danish, Dutch, English, Esperanto, Estonian, Faroese, Finnish, French, Frisian
Galician, German, Greenlandic, Hungarian, Icelandic, Irish Gaelic (new orthography), Italian, Latvian, Lithuanian, Luxemburgish, Maltese,
Manx Gaelic, Moldavian (new orthography, with restrictions), Northern Sami, Norwegian, Occitan, Polish, Portuguese, Rhaeto-Romanic,
Romanian (with restrictions), Scottish Gaelic, Slovak, Slovenian, Lower Sorbian, Upper Sorbian, Spanish, Swedish, Turkish, Welsh
Here is the chart:
https://docs.google.com/spreadsheets/d/1ok7-yZKT2pJ4_3o0LZTLytMxqnQGc5yQtc3mHyyuES4/edit?usp=sharing
It should include all 335 characters of MES-1. For every single character, it is indicated how you can type it most efficiently in
my layout proposal. Yes, it is a bit of a mess. Languages are messy things.
I found one 'bug' in my assumptions: even though Ł can in a sense be considered as L with kreska, which is a Polish acute, we cannot use dead acute + L for
Ł ł because L with acute (
Ĺ ĺ) also exists (in Slovak), which is by the way not to be confused with L with caron (
Ľ ľ) where the caron usually looks like an apostrophe. To solve this, and to also cover the Croatian Đđ, the Danish/Norwegian Øø, the Maltese Ħħ and the Northern Sami Ŧŧ, I decided to follow the Compose convention and use slash / for letters with a stroke or crossbar. Shift+/ can act as a dead diacritic to produce ĐĦØŁŦđħøłŧ.
I also added Shift+minus for dead macron, to get ĀĒĪŌŪāēīōū.
Here are the conclusions in terms of coverage:
The only letters that are not covered in two thumb presses by my layout are the following:
Ææ Œœ Þþ Ðð Ŋŋ ĸ. For these you would need a Compose sequence (AE OE TH DH NG KK respectively), which takes three thumb presses. This makes typing Danish (5.5 million speakers), Faroese (66,000), Greenlandic (60,000), Icelandic (330,000), Northern Sami (~25.000) and Norwegian (5 million) less efficient to type. (For French, the missing Œœ is not a big deal).
The biggest problem is for Danish, where
Æ has a letter frequency of 0.97% (which is between that of K and V in English). In Norwegian, Æ has a letter frequency of 0.26% (about the same as the letter J in English). So having an easier way to type Æ would be useful. Perhaps it would be justified to remove § (so you would have to do Compose S O) and replace it with Æ. On the other hand, it is weird to have one-thumb Æ but still need two thumb presses for Å and Ø, which are more important letters than Æ in Danish and Norwegian. So I think that it makes more sense for Norwegians and Danish people to just remap Å Ø Æ (in their favorite positions, which differs between Danish and Norwegian keyboards) over Ü Ä Ö, which is probably something they are somewhat used to do if they ever typed on a German or Swedish keyboard before.
The other symbols (Þþ Ðð Ŋŋ ĸ) for which you are forced to use the Compose method, are only used for Faroese, Greenlandic, Icelandic and Northern Sami (total number of speakers: less than 0.5 million).
Note: do not confuse the
Ðð (eth) of Old English, Faroese and Icelandic, which I don't efficiently support, with the
Đđ (dyet or crossed D) of Serbo-Croatian languages (~19 million speakers)
[and, incidentally, Vietnamese (~75 million)] which is available in two thumb presses.
To go back over the list of languages: I have indicated the languages that are supported perfectly in
bold (meaning that all letters are available in one thumb press, or two thumb presses
if the letter would also require two thumb presses on a standard keyboard for that language). The others need at most two thumb presses per letter, which is still quite reasonable, except the ones
in red which need Compose sequences (so three thumb presses) for some letters.
Languages with more than 10 million speakers are in a larger font, and languages with more than 100 million speakers are in an even larger font.
Afrikaans, Albanian,
Basque,
Breton,
Catalan, Croatian,
Czech,
Danish,
Dutch,
English,
Esperanto, Estonian,
Faroese,
Finnish,
French,
Frisian,
Galician,
German,
Greenlandic,
Hungarian,
Icelandic,
Irish Gaelic,
Italian,
Latvian, Lithuanian,
Luxemburgish, Maltese,
Manx Gaelic, Moldavian,
Northern Sami,
Norwegian,
Occitan,
Polish,
Portuguese,
Rhaeto-Romanic,
Romanian,
Scottish Gaelic, Slovak, Slovenian, Lower Sorbian, Upper Sorbian,
Spanish, Swedish,
Turkish,
Welsh
I'm quite happy with this coverage. The Scandinavian languages (including the insular ones) are the biggest remaining problem. I see no easy solution for them, except just using something US-International or remapping üäö to åæø.