[FIXED] Interpolation issue with close axis location
[FIXED] Interpolation issue with close axis location
When axis locations are very close, interpolation corrupts as shown the image attached.
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- 2021-07-05 155150.png (281.58 KiB) Viewed 3788 times
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Re: Interpolation issue with close axis location
It doesn't look right, but we can't determine the cause without inspecting the font, so please send it to us.
Re: Interpolation issue with close axis location
Here it is.
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- Xor7Seg_Variable_V1.0.fcp
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Re: Interpolation issue with close axis location
Thank you for providing the font. I assume you made it with another font editor?
Anyway I think I have a fix for it, but please verify if it now works as expected.
https://www.high-logic.com/tmp/fontcrea ... 97-x64.exe
Anyway I think I have a fix for it, but please verify if it now works as expected.
https://www.high-logic.com/tmp/fontcrea ... 97-x64.exe
Re: Interpolation issue with close axis location
Now works as expected. Thank you.
I guess I'll need conversion tool soon as converting curve will be tedious though.
I use Blender as design tool because it accepts formula as input and I think working with edges is better for me,and then convert coordinates via calculator to FontCreator.I assume you made it with another font editor?
I guess I'll need conversion tool soon as converting curve will be tedious though.
Re: Interpolation issue with close axis location
Sorry for raising the issue again, but I found this problem is not solved entirely yet.
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- Xor7Seg_Variable_V1.0.fcp
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Re: Interpolation issue with close axis location
I suspect those are all bugs in your font. Can you show a glyph that you think should interpolate correctly, but fails to do so?
Re: Interpolation issue with close axis location
In certain range, all glyphs are interpolated with default master instead of two masters that covering the range.
Maybe my font has too close masters but I don't know how far the value to be to hide intermediate state.
Is 1/65536 between masters too close?
Maybe my font has too close masters but I don't know how far the value to be to hide intermediate state.
Is 1/65536 between masters too close?
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Re: Interpolation issue with close axis location
If it is an issue on our side, please provide a way for us to reproduce it.
Such small difference can not be stored in the internal font format. For each axis, the master location is stored in a 16-bit signed fixed number with the low 14 bits of fraction (F2DOT14).
Re: Interpolation issue with close axis location
Sorry, I didn't notice there is normalization for the coordinate values which causes a lot of precision loss.
I modified the gap to 1/8192 and now problem is gone.
By the way, you wrote:
I modified the gap to 1/8192 and now problem is gone.
By the way, you wrote:
I assume you are talking about normalized coordinate system used in avar table, however, I'm talking about coordinates in fvar table which stores the coordinates as Fixed (16.16) data type and that's why I used 1/65536 as gap previously.For each axis, the master location is stored in a 16-bit signed fixed number with the low 14 bits of fraction (F2DOT14).
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Re: Interpolation issue with close axis location
Perfect.
Tuples are stored as F2DOT14.File_xor wrote: ↑Tue Jul 13, 2021 5:39 am By the way, you wrote:I assume you are talking about normalized coordinate system used in avar table, however, I'm talking about coordinates in fvar table which stores the coordinates as Fixed (16.16) data type and that's why I used 1/65536 as gap previously.For each axis, the master location is stored in a 16-bit signed fixed number with the low 14 bits of fraction (F2DOT14).