Written Cantonese input? Although traditionally Cantonese speakers just use standard Chinese (mostly Traditional in my experience) for writing and reading, written Cantonese does exist as you can read about in this Wikipedia article.  I'm curious as to whether there exists any input system for this written Cantonese.  I specifically use Windows, but I'd be interested to know about systems for Mac and Linux as well.

If not, do most or all the characters used for written Cantonese exist in other Chinese input libraries?  I ask this realizing that many of the characters in written Cantonese are simply re-purposed, but I also know that many of them are other characters with the addition of a leading 口 character and I don't know whether those exist outside of written Cantonese or not.  Please enlighten me!
Correct me if I am wrong, but I believe all Cantonese characters (theoretically) have pinyin representations. Examples:


冇 (have not) / Yale: mou5 / Pinyin: mao3
佢哋 (they) / Yale: keui5 dei6 / Pinyin: qu2 di4
咗 (similar to 了) / Yale: jo2 / Pinyin: zuo3
嘢 (thing) / Yale: ye5 / Pinyin: ye3


But in my experience, using a Standard Chinese Pinyin IME to enter Cantonese characters is just not natural. Sometimes characters are missing. Some commonly used characters are way down the list.

One solution is to use a Cantonese IME like this one. There are even online tools to input Cantonese.