Re: Western vertical texts

On 3/1/2012 10:14 PM, Ambrose LI wrote:
> Oh, sorry, I missed that part. I guess he did say UA dependent then, 
> for the specific use case of text-orientation:upright plus fonts that 
> do not have vertical metrics.

What I meant by "give room for implementations" is fairly broad. It did 
include "UA dependent", but it also included "do not impose 
costly-to-implement behaviors that do not work too well anyway". For 
example, imposing to use the bounding boxes is certainly more expansive 
than using a glyph-independent metric.

On the topic of "UA dependent", I find the term somewhat too binary to 
account for the real world. Unless and until the specifications give a 
complete description of the result down to the pixel, there will be some 
variation between implementations; the question is what is tolerable. 
And even getting to a narrow range to variation will be tricky without 
diving heavily in the font specifications. Finally, some areas will 
probably never be in reach of standardization: bounding boxes come to 
mind, at least when they account for rasterization artifacts.

Eric.