Re: [Devel] beating the patents - an idea

[Antoine Leca]

Hi,

Disclaimer: I am not a lawyer.

address@hidden wrote:
> 
> * To get around the patent problem with true type font rendering,
> -would it help at all to provide your own "hint-files" to accompany
> many of the main popular ttf fonts? (arial, times new roman etc.) thus using
> your own database of good hinting adjustments at various common small sizes?
> The rendering engine would look for a corresponding "hint file" for the
> font it was using and read the list of hints from it for the size, angle
> etc. that it was trying to render.

Hmmm, that is really extending the idea of the delta's. Can someone with:
 a) good understanding of patent laws
 b) good knowledge of the patent about deltas
 c) free time (since David qualifies a lot for the first two, I should give
    him a way to escape ;-))
verify if this will be a violation of the patent about delta's?
I believe the idea is good, but the lawyers at Apple may be clever too...


> In fact, would it break any patents to use your existing rendering engine
> (with a license) to generate the list of hints for you?

You should check:
  a) this is not a violation of Apple license (the one Apple grants you
   to be able to use officially the bytecode engine inside Freetype); I have
   no idea about that;
  b) that this is not a violation of the license of the TTF itself. At least
   regarding Microsoft files (Arial, Times-New-Roman, etc.), it seems to me
   that their license is rather contrived in such areas, such I believe this
   could be prohibited...


> you could make a
> custom version of it which outputted the hints to a file.
> (perhaps the patent only covers the formulae, not the actual values of the
> hints...)

In any way, the patent covers the "apparatus", that is the process that is used,
in this case the patents cover
- one, the fact to use projection vectors (I oversimplify), that is, the very
basics of writing TrueType hintings (which is irrelevant to you, since it is
about two levels remote)
- two, the use of delta's, that is indications that in certain conditions, a
point should be moved to another pixel. As I implied above, your idea can be
seen as converting all TrueType hinting into deltas, i.e. operations to apply
to the scaled outline to appear aesthetically correct at specific ppem.
What I do not know, is if this idea is encompassed in the Apple patents.


> You might even be able to provide the customized engine to those who wanted
> it to create their own hint files for their own fonts which they might have
> hinted themselves.

Another idea is to store "your" hints inside the ttf, in a different table.
This way, there is no need for the separate hint-file.


Antoine