In order to identify the BlueValues etc, I read that the AFDKO stemHist tool is able to identify a series of values to work with. However, I have some difficulties installing it due to incompatibility with Python versions.
Waiting to resolve this problem, it seems to me that FontLab suggests or imposes values in a more or less automatic way. In the meantime I would like to see what values set, but generally working with FontForge from Linux I know very little about FontLab, of which I installed the trial version in the Windows partition.
I could not find the tool or window from which to do this. In FontInfo I only see the data with the original settings. How can I perform this reset operation with the values suggested by FontLab?
Moreover: can I work on a otf for this?
Thank you
Comments
BlueValues:
Standard Stems:
You can click on the button with ruby in both windows and FL will try to calculate values automatically
I don't find the voices you are speaking about...
I don't know exactly how it works in FL6, but I think that you should look somewhere there to find necessary values.
Rendering in Windows (both with Adobe Acrobat Reader and Edge) show some flaws.
The most obvious here is the glyph of the "z", not aligned and lower than the others. What can it depend on?
this information can be used for StandardStems values.
I think you should read OpenType Adobe specs document to get better understanding of postscript hinting and its params.
https://forum.fontlab.com/fontlab-vi/bluescale-value-12136/msg41147/#msg41147
https://glyphsapp.com/tutorials/hinting-manual-postscript-hinting
https://glyphsapp.com/tutorials/hinting-postscript-autohinting
I have modified some values and in fact now the defects are very reduced. The glyphs rest (almost) all correctly on the same baseline.
However, there are some residual defects, related to specific glyphs and to certain resolutions on Windows both with Adobe Acrobat Reader (I have already tried to change the hinting settings, but without result) and with Microsoft Edge, while on Linux you always see well.
For example with a display below 100% and at large resolutions the glyph of the letter "v" is badly seen, while those of "m" and "n" have curved lines that are too thin and appear taller than the other glyphs. The "x" glyph very appears very small. I enclose two screenshots from Adobe Acrobat Reader, the first with a 92% zoom, the second with a 197% zoom.
In case, I can post a link to the .otf, if anyone can take a look at the values I set. Thank you
Screenhot 92%
Screenshot 197%
then I deleted the previous hintings and I redid the autohinting.
However, little has changed.
These are the settings:
and this the otf: https://www.dropbox.com/s/lak6dslz3zxbbtp/TestPro.sfd?dl=0
Is it too much if I ask for a verification of the parameters?
This way only can I understand the actual errors I continue to make
Thanx a lot!
And also you have a lot of redundant nodes in contours in my opinion.
But changing bluezones and bluefuzz=5 gave me this result:
This is only an example and not final values for you.
I strongly recommend you spend the evening reading the opentype specs, pay attention to Flex hints.
Font alignment depends on bluevalues + bluescale + blueshift + bluefuzz
Font width depends on standardstems + glyph level hints
https://glyphsapp.com/tutorials/hinting-postscript-autohinting
https://glyphsapp.com/tutorials/hinting-manual-postscript-hinting
Read at least these tutorials to understand how parameter values interact with each other and affect rendering. Then look for the values that best fit your font in practice.
Bluefuzz is overused, I think. At least half of fonts can have bluefuzz set to zero.
If you want to share your font file, I would be curious to see what is going wrong with the "z"
https://www.dropbox.com/s/v3y5ni8kjb9eckv/TestdPro.otf?dl=0
Why you have such a massive blue shift, I don't know. Is there some reason for that? I would say that most fonts are best served by blue shift of zero.
I suggest sharing your font with Fontlab support at https://support.fontlab.com so people can actually look at your glyph outlines relative to the blue zones. The blue zone values by themselves don’t tell us much.
These are the settings:
I don't understand the meaning of the last couple of values, which are the same ones (750 750).
BlueShift is still set to 6. I will try to set this parameter to 0 and review everything, because, even though I proceed by trial and error, I start to understand something
[40, 44, 49] = 44
[54, 62] = 58
[34, 42] = 38
[65, 66, 67, 70, 72] = 69
[81, 82] = 81
Otherwise, the render may be confused by your values.
750 is ascender height of b and d
Your fl liga height is 743 you can try to set (743, 750) instead of (750, 750)
Note that there is not a single set of right answers to this question of stem snap values. In general, one’s choices could and perhaps should be influenced by the frequency (and possibly relative importance) of the stems in question. For example, within one set of stem values, if one particular value is much more common or more important than the others, you might either use it, or weight it appropriately in the average.
- it will not work so well at more modest resolutions/sizes (lower ppem sizes)
- it will do especially badly in older non ClearType Windows rendering systems. Such rendering can sometimes be invoked even on versions of Windows that support ClearType.
You can always try other systems if doing it the usual way is too difficult. TTFautohint for example generally produces fairly decent results. FontLab VI has TTFautohint built in, as an option/alternative....I do not understand instead the criteria of assignment of StemSnapH and StemSnapV, nor how many values should be inserted. Any suggestions?
And should be the StdHV and StdVW the most statistically frequent values?
Thank you very much