Re: [fontforge-users] Error Message "is not a valid font file"

[<ms...@an...>]

On Tue, 25 Aug 2015, marty39 wrote:
> Aha! Fontforge says the convention is that TrueType fonts should have an
> Em-size that is a power of 2. It gave me that warning when I tried to create
> a TrueType font with an em-size of 1000, saying that it wasn't an error,
> just conventional. TrueType fonts usually have an Em-size of 1024 or 2048,
> but Windows can accept other Em sizes.
>
> Maybe in this case the em-size was just too small for Windows. For your
> purposes it would have to be a multiple of 10, so 100 works.

I've experienced problems with Windows PDF viewers and fonts whose em
values are not powers of two; sometimes the PDF viewer will seemingly
choose a new em value of its own and use that instead of the one in the
font, resulting in characters that are located at the correct points on
the page but significantly larger or smaller than they should be.  I think
it's a really bad idea to attempt to use a nonstandard em value, even if
the standard claims doing so is allowed.

-- 
Matthew Skala
ms...@an...                 People before principles.
http://ansuz.sooke.bc.ca/