Re: [Freetype-devel] Re: GSOC - Distance Fields

[suzuki toshiya]

Dear Anuj,

I agree with Werner's comment.

It might be uncomfortable for you to leave an untested question, something
like "if I use a floating point calculation, the result could be better?".

Please use a floating point in your initial draft (if you want),
and let's discuss about the trade-off with the implementation
with no floating point, in later.

Regards,
mpsuzuki

On 2020/05/13 6:14, Alexei Podtelezhnikov wrote:
> I'll just add references below.
>
> On Tue, May 12, 2020 at 4:15 PM Werner LEMBERG <address@hidden> wrote:
> > > I can't decide which format to use for storing the SDF(signed
> > > distance fields).  I think using floating-point values (fixed-point
> > > in this case) for generation will be more accurate than using
> > > integer, but then saving the SDF to a file will require a
> > > conversion.
>
> The basic types are described here:
> https://jpn01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fwww.freetype.org%2Ffreetype2%2Fdocs%2Freference%2Fft2-basic_types.html&amp;data=02%7C01%7Cmpsuzuki%40hiroshima-u.ac.jp%7Ce744d4df60514a93796908d7f6b97d4b%7Cc40454ddb2634926868d8e12640d3750%7C1%7C0%7C637249148842533871&amp;sdata=%2FVbt%2BfNz6x24eJNK9ag1PDhZXz49rS4b64fcmMJ2G9A%3D&amp;reserved=0
> The computations are described here:
> https://jpn01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fwww.freetype.org%2Ffreetype2%2Fdocs%2Freference%2Fft2-computations.html&amp;data=02%7C01%7Cmpsuzuki%40hiroshima-u.ac.jp%7Ce744d4df60514a93796908d7f6b97d4b%7Cc40454ddb2634926868d8e12640d3750%7C1%7C0%7C637249148842533871&amp;sdata=T%2BQR9KKVWo%2BEI4Lqr5vFkgguWHV8xm8BB3USWcaQ8iY%3D&amp;reserved=0
> Saving files is not of FreeType's business. We just return data.
>
> > The basic question is whether the accuracy is really needed.
> > Currently, FreeType doesn't use floating-point arithmetics.
> > Personally, I would favour a solution without floats, but maybe there
> > are good reasons for using them.