I do not use Japanese, but I cannot confirm that TE is slow when in any position. Perhaps this is a topic of Apple feedback (Apple Bug Reporter), if you assume this is correct. On the other hand, perhaps other users of Japanese in Mac OS X may help.
If you are not satisfied with TextEdit, you may test other two wonderful word processors, Nisus and Mellel, both work on shareware basis (test before you buy), if you are satisfied, buy the one you like and / is appropriate for your work. TE is a simple editor far basic work and even for programming, not for word processing in its full sense. You may also test the free OpenOffice and, of course, MS Office.
Cattus Thraex wrote:
If you are not satisfied with TextEdit, you may test other two wonderful word processors, Nisus and Mellel
Unfortunately it is not common to find the vertical layout used in Chinese/Japanese in a word processor -- Nisus, Mellel, and Pages do not have this feature. I think only MS Word, iText, and Jedit X can handle it, plus the latest TextEdit.
in Vertical layout, everything takes ~2/3 times longer. When I hit an arrow key, it takes nearly a second for the cursor to move, and while using Kotoeri (Kana/Kanji input) the speed is practically unbearable.
I only know a couple words of Japanese, but when I tried typing both english and japanese text in vertical format in TextEdit it seemed just as fast as horizontal, I could not see any lags. Are you using any unusual fonts, or just those supplied with OS X?
PS You might want to ask whether anyone typing Chinese has had similar problems on the Chinese Mac list:
I'm using an Apple supplied font (Hiragino Kaku Gothic Pro (Japanese Font)) as listed here (Cmd/Ctrl+F Hiragino). The Hiragino are the only fonts I've used so far and I remember TextEdit working like normal (As you've said yours has been working) a few days ago, but, like I said, now it's started to run pretty slow with vertical layout enabled.
EDIT: Well, I guess TextEdit hates spaces. I removed all the spaces (the only reason I was using spaces in the first place was because this is a speaking assignment and It's easier to seperate each segment), and it runs at normal speed once again. I guess I'll file a bug report for the spaces in TextEdit in vertical layout (And yes I tried spaces in Vertical with English too, still unbearably slow). What I noticed is that the performance slowdown builds up, it starts getting slow after the first space or two but then makes a dramatic differenc in speed as more spaces are added. Thanks everyone for the help.
I tried English with tons of spaces and could not duplicate your experience (in which case Apple may also not be able to do so). I don't know what might cause your problem. Any text related add-ons on your machine?
I suppose you could type horizontally at normal speed and then just do Format > Make Layout Vertical at the end?