[cairo] Struggling with subpixel text (last blocker for 1.8)

[Bill Spitzak]

"subpixel rendering" is not just for fonts. It can certainly be used for 
antialiasing of everything else Cairo draws. For that reason it makes a 
lot more sense for Cairo to be doing it, not FreeType. All that is 
needed from FreeType is images at a higher resolution (the input to the 
filter).

Therefore, whatever the legal ramifications, this certainly should be 
part of Cairo and turned on/off in it.

I believe you can avoid the patent by not filtering. This produces very 
annoying color fringing. You can also use an error-diffusion method to 
distribute the colors. Another technique I saw was to only use two 
"subpixels", one of them is green and the other is magenta, this can 
actually produce sharper images, and avoids the patented filter.

-- 
Bill Spitzak, Senior Software Engineer
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