(see also parts 1, 2, and 3) 

OK, we are getting close to the end of this little mini-series....

First there was a comment from Dennis E. Hamilton asking about the DPI in the screen shots of that first post:

I notice two things here.  First, the impact of Cleartype is amazing.  Secondly, the Vista rendering seems fuzzy somehow and not as crisp as the XP SP2 Cleartype.  I realize the sizes are different, with different assumed resolutions, but the subjective experience at scale is important.  (I think I see this on my Vista-equipped Tablet PC too, so I really wonder ... )

If you use the same DPI, how well does Vista match the XP Cleartype case?

I decided to engage in a bit of experimental DPI viewing. I used the funniest string from Why that is positively Ethiopic! (፳፩፼፳፰፻፷፯፼፶፫፻፱) and took screen shots at 96, 120, 134, and 144 DPI (note that I did not change the sample application; I just pasted the string into the TextBox controls):

I'll let you decide on your own about the quality (the code was unchanged so it was trying to use a 32pt size for the font in all four cases).... :-)

Now the additional issues to keep in mind here for font embedding....

First we'll take a look at Nyala's OpenType support from 10,000 feet:

Notice that it does have some OpenType tables that provide support for Ethiopic, though the main reason to consider Ethiopic to be a complex script is for that undocumented sixth reason to be considered s complex script that I described in Font Linking vs. Font Fallback, #2.

The technology provides the selected [subset of the] font and allows you to embed it in your application if the font's licensing restrictions allow it. But it does not give you updates to shaping engines and it does not give you pieces of the font that are excluded by subsetting decisions you might make. In the end, this means that any time the language you are trying to display is a complex script, the proper display might be limited by what the machine itself can support (for an example of this imagine some of the complex scripts added in Vista like Khmer or Sinhalese or Tibetan and try to imagine displaying them in Windows 2000!).

XP SP2 will actually do very well here, much better than one might expect at first. But it turns out that the update to the Uniscribe shaping engines provided by the update I first described in Lions and tigers and bearsELKs, Oh my! included some of the (not completely finished but certainly in progress) updates that eventually made their way into Vista. So you may find you have better luck in XP SP2 then in most other downlevel platforms. But n matter what you will always have the constraint of the platform's support to contend with.

This also applies to keyboards (you'll have to provide them via MSKLC or whatever), locale support (custom cultures, anyone?), or collation (currently no solution for this one, sorry -- so beware this problem!).

You will probably always want to be using .NET Framework >= 2.0 so that you can use Uniscribe and not be limited to what GDI+ supports.

And then when you are done, be sure to call TTDeleteEmbeddedFont as the sample does in its FormClosing event. And in your real world samples you probably should embed the font in your application's resources and then just use a MemoryStream rather than a FileStream to read it (though even is you treat it as a file like the sample does, there is not really anything else that you can do with the file anyway....

As a final note, let me once again remind people to follow the licensing restrictions of the font you want to use. Your font foundry will thank you for attention to your attention to this particular detail!

 

This post brought to you by ጵ (U+1335, a.k.a. ETHIOPIC SYLLABLE PHE)