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

[Anuj Verma]

Hello All,

>> One more thing.  I think the OpenGL demo is not good for everyone to
>> test, so I will working on a demo similar to 'ftview' in my spare
>> time.
>
> Great!

I have created the demo program, it can be used to view raw SDF without

any bilinear filtering and there is no way to reconstruct fonts from SDF because

again it doesn't have bilinear filtering. I will add that soon.

There is a pretty weird issue that I ran into while testing the demo on linux

which doesn't happen on windows whatsoever. On linux various computations

give wrong output. For example, division of  -328032 by 64 gives 1811934202,

whereas it should be -5125. Moreover FT_Vector_Length returns negative values

even for small vectors. There is no overflow so what am I doing wrong?

(One of the places it happens is: https://git.savannah.gnu.org/cgit/freetype/freetype2.git/tree/src/sdf/ftsdf.c?h=anuj-distance-field#n1129

 where the `factor' is wrong after division with 64).

I am using gcc version 9.3.0 (Ubuntu 9.3.0-10ubuntu2)

and GNU Make 4.2.1 to build.

If you need more details please let me know.

You can check out the demo here: https://github.com/preversewharf45/ft2sdf-demo

The build process is the same as ft2-demos. The freetype2 library is added as a submodule

so use --recursive. And it only works properly on windows. There is no comments of help

screen so I'm attaching a text file for that.

Thanks,

Anuj

controls.txt
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