as an historical linguist dealing with old germanic languages, i need a convenient way to input special characters on my computer. since I want to be able to use these characters across all my applications (text editor, office suite, email-client, browser), a per-application solution is not a good idea. a better approach is to change the keyboard layout system wide. luckily, this can be achieved easily on a linux system by customizing one of the predefined X11 keyboard layouts. in my case, i came to the conclusion that it was best to modify the existing keyboard layout definition for us-english (called “us”) by adding a new “layout variant“, which i decided to call “altgr-gmc”. as you can see, every key is bound to four different characters. the characters on the right side of every key can be accessed by using AltGr (bottom right) and AltGr+SHIFT (top right) as modifiers.

here's what i came up with (click for a larger image):

the distribution of characters across the keyboard is somewhat arbitrary, though i tried to keep compatibility to “altgr-intl” if possible, and i strived to make the rest as intuitive as possible (r-sounds on the r-button, combining diacritical mark for a stroke below on the hyphen-button, since it sort of looks like a little rotated hyphen etc.).

if you want to give it a try, follow these instructions (root permissions required for all steps):

1. adding the new layout variant
   open the file /usr/share/X11/xkb/symbols/us and append these lines at the end of it.
2. enabling it in X11
   edit /usr/share/X11/xkb/rules/evdev.xml and add the following lines at a suitable position (e.g. after the entry for “altgr-intl”):

           <variant>
             <configItem>
               <name>altgr-gmc</name>
               <description>for Old Germanic</description>
               <languageList><iso639Id>eng</iso639Id>
                             <iso639Id>fra</iso639Id>
                             <iso639Id>ger</iso639Id></languageList>
             </configItem>
           </variant>

   you may also want to make a corresponding change in /usr/share/X11/xkb/rules/evdev.lst for consistency's sake (it doesn't seem to be required).

3. setting it as system default
   open /etc/default/console-setup and set XKBVARIANT to "altgr-gmc". make sure that the variable XKBLAYOUT points to the file that you modified in step 1 ("us")
4. restart your computer

(this was all done on a xubuntu 9.10 system. should also work on any other recent ubuntu installation.)

a few problems remain, mostly related to the handling of combining diacritical marks. contrary to my initial plans, i ended up refraining from the use of “dead keys” in favour of using combining diacritical marks throughout. this happened for consistency's sake. in general, i prefer to use precomposed characters (which is what the “dead keys” give you), but since precomposed characters are not available for all the desired combinations, it's unavoidable to use combining diacritical marks in some cases, and because of that it seemed better to me to use the latter throughout. of course it would be best to have a “fall back strategy”, so that precomposed characters will be used whenever possible, and combining diacritical marks elsewhere. such a solution doesn't seem possible currently, however, since you can only use a key either as a “dead key” (which will give you no character at all in the case that you choose an unavailable combination) or to have it produce a combining diacritical mark.

a second thing that's been irritating me is that the handling of combining diacritical marks seems to be very inconsistent across applications and fonts. strangely, changing the font of my text editor does not only change the way the marks are displayed in the editor window (sometimes combined, sometimes simply next to each other), but it can also (in some cases) change the order in which i need to input the base letter and the modifier: depending on the current font, i sometimes have to type the diacritical mark before and sometimes after the letter i want to modify... isn't that odd?

another issue is that stacking diacritical marks is messy. often, the marks will end up being superimposed on each other instead of being stacked. it's basically a matter of trial and error to see what will work and what won't :(

so here's a sample of what you can do with “altgr-gmc”, including some fancy (but not always neatly typeset) stacked diacritical marks:

links:
http://people.uleth.ca/~daniel.odonnell/Blog/custom-keyboard-in-linuxx11
http://www.mufi.info/ Medieval Unicode Font Initiative
http://unicode.org/charts/
http://unicode-search.net
http://en.wikipedia.org/wiki/Unicode

1. make yourself comfortable in your living room and drink a bottle of wine (or two)
2. by the time you finish the wine, you probably had at least one brilliant idea about the meaning of the inscription (which you only had a brief look at on a blurry, black and white photograph)
3. flip through some old germanic dictionaries looking for words that might fit your interpretation. don't worry if the words don't look like the words in the inscription - you will see how to fix that in the next two steps
4. make some wild phonological and morphological assumptions required to make the words you want to read look more like what is actually on the stone/object. feel free to use any endings you may find in any of the germanic languages, and combine them with any stem you may seem fit. if you can't find the endings you need, you simply make up new ones and call them "old variants inherited from PIE" (cite some arbitray sanskrit forms to prove that these endings really existed). if you run into chronological problems, simply claim that the archeological dating must be wrong, or rearrange the established chronology of sound laws in any way you please.
5. make any further assumptions needed for your interpretation. choose from among the following:
   • you may read any single rune as a "begriffsrune", no matter if it stands separately, at the beginning, the end, or even in the middle of a word
   • don't worry about word boundaries: you may read them as i-runes whenever it suits your needs, declare them as scratches or just ignore them altogether
   • conveniently, ornaments can always be read as runes and vice versa
   • feel free to ignore any runes, even if they are clearly visible, add elements (twigs, crooks) to existing runes, or claim that you can see runes, even if there is nothing there on the photograph to justify it. If you are still in need of an additional rune, you can claim that the rune master simply forgot to write it. you may also replace any rune with another one and call it a "misspelling". remember: doubts are best covered up by bold claims!
6. call any remaining parts of the inscription "magical words"
7. publish!

our copy machines at the university can scan documents and send them to an email address. how convenient! however, when you scan pages from a book, the page-size will most likely not match the exact size of an A4 paper, resulting in a PDF document that has black borders on the side and/or the bottom. this is bad, because printing these pages later will waste a lot of ink. that's why i've been looking for an easy way to crop PDF documents on linux, and i've finally found out how to do this:

pdfcrop --margins '0 0 0 -50' --clip report.pdf

this will remove 50 bp from the bottom of every page of the PDF.

on my distro, pdfcrop is provided by the package 'texlive-extra-utils', so you'll need to install this if you don't have it already.