I’m in the process of sorting the paperwork with my employer as well. I will send an update to this thread when it’s confirmed and the copyright papers have been signed. Kind regards, Stanislav Yaglo ________________________________ From: bug-gnu-emacs-bounces+yaglo=me.com@gnu.org on behalf of Po Lu via Bug reports for GNU Emacs, the Swiss army knife of text editors Sent: Monday, June 12, 2023 2:31:11 PM To: Stanislav Yaglo Cc: 64013@debbugs.gnu.org <64013@debbugs.gnu.org>; YAMAMOTO Mitsuharu Subject: bug#64013: [PATCH] macfont.m: Fix values for font widths and weights on macOS Stanislav Yaglo writes: > Hi everyone, > > Currently, on macOS, font weights are not handled correctly, which causes Emacs to choose different font weights and widths than what you > request. As one example, if you want to choose "Cascadia Code:weight=semi-light", you will get Cascadia Code Light instead. Same for font > widths, what you specify is not always what you get. > > There's some interpolation going on which I didn't remove as it's potentially handy for in-between values, but the problem itself is that the > corresponding values are not correct for the majority of fonts, for example, kCTFontWeightTrait is specified as -0.24 corresponding to 87.5 , but > in reality, it is usually 50 (light), and the same for the other values. As you can see here, it won't work as we have 50 followed by 87.5 and then > (a lower) 80, and then 140: > > {-0.4, 50}, /* light */ > {-0.24, 87.5}, /* (semi-light + normal) / 2 */ > {0, 80}, /* normal */ > {0.24, 140}, /* (semi-bold + normal) / 2 */ > > It probably is a typo, as in the second (duplicate) table of values in the code, 100 is treated as normal instead of 80, which also isn't correct, as > 100 is medium, not normal: > > {-0.4, 50}, /* light */ > {-0.24, 87.5}, /* (semi-light + normal) / 2 */ > {0, 100}, /* normal */ > {0.24, 140}, /* (semi-bold + normal) / 2 */ > > For font widths, there's only two kCTFontWidthTrait values in the range that are handled currently — from 0 to 1, and they are handled as > linear font values from 100 to 200, which isn't correct either. For condensed fonts, kCTFontWidthTrait is negative, which is not accounted for, > and the slope is linear only from -0.4 (50, ultra-condensed) until 0.2 (125, expanded), and from there until ultra-expanded is much steeper. > > I've included all values that are listed in font.c for explicitness even if some values can be calculated with the code that interpolates the values. > Also, I haven't refactored the duplication of the structs and code as I think this is a different issue and should be done separately to keep this > patch on point of the issue being fixed, and I will probably submit a patch for this later to avoid code duplication and potential issues in the > future as with the current 80/100 problem mentioned above. > > Kind regards, > Stanislav Yaglo Thanks. Have you signed copyright papers for this change? I've also copied in YAMAMOTO Mitsuharu , who might have additional comments on this code.