Hi Werner, > > I am a bit concerned with 16-bit SDF. It comes in *whatever* > > platform endianness. It is probably an overkill and 8-bits would > > work just fine because the distance does not have to be expressed in > > "pixels". For example, it can be scaled to signed [-128,127] with 0 > > threshold, or unsigned [0,255] with an arbitrary threshold. We did > > not have a good discussion on this. > > I have no opinion on that. If you think this should be further > discussed I suggest that you do it now :-) On the other hand, I > think there *was* some discussion regarding 8bit vs 16bit. Have you > looked up the freetype-devel mailing list archive? I seem to remember > that there were good reasons for 16bit.
We discussed the format but did not make any decisions. We might have a property to select between 8 and 16 bits. I originally thought that SDF had to contain actual distance in pixels.That is not necessary because it is subject to interpolation and thresholding and can be normalized arbitrarily, e.g from 0 for -spread to 255 for +spread.The default choice should be a matter of convenience.I would like to hear some opinions on this.