foot detects DPI incorrectly after resing font #9

nikp123 commented 2020年03月14日 20:42:50 +01:00

How to reproduce:

1. Launch foot
2. Try to resize font with keyboard shortcut ctrl in combination with either + or -

Expected behaviour:
Font scales properly when trying to resize

Issue in detail:
The font doesn't get scaled linearly because when resizing foot doesn't read the DPI correctly

Attached log - (describes the bug):

nikp123@HP-Laptop /home/nikp123 $ foot
info: config.c:841: loading configuration from /home/nikp123/.config/footrc
info: wayland.c:798: HDMI-A-1: 1920x1080+1092x0@60Hz 2343 23.10" scale=1 PPI=96x98 (physical) PPI=96x98 (logical)
info: wayland.c:798: eDP-1: 1366x768+0x645@60Hz 0x0354 13.23" scale=2 PPI=124x128 (physical) PPI=99x102 (logical)
info: wayland.c:834: cursor theme: (null), size: 24
info: terminal.c:482: using 4 rendering threads
info: wayland.c:1027: requesting SSD decorations
info: fcft.c:451: /usr/share/fonts/TTF/TerminusTTF.ttf: size=12.00pt/32px, dpi=196
info: fcft.c:451: /usr/share/fonts/TTF/TerminusTTF-Bold.ttf: size=12.00pt/32px, dpi=196
info: fcft.c:451: /usr/share/fonts/TTF/TerminusTTF-Italic.ttf: size=12.00pt/32px, dpi=196
info: fcft.c:451: /usr/share/fonts/TTF/TerminusTTF-Bold Italic.ttf: size=12.00pt/32px, dpi=196
info: terminal.c:526: cell width=16, height=35
info: wayland.c:634: using SSD decorations
info: fcft.c:451: /usr/share/fonts/TTF/TerminusTTF.ttf: size=12.00pt/34px, dpi=204
info: fcft.c:451: /usr/share/fonts/TTF/TerminusTTF-Bold.ttf: size=12.00pt/34px, dpi=204
info: fcft.c:451: /usr/share/fonts/TTF/TerminusTTF-Italic.ttf: size=12.00pt/34px, dpi=204
info: fcft.c:451: /usr/share/fonts/TTF/TerminusTTF-Bold Italic.ttf: size=12.00pt/34px, dpi=204
info: terminal.c:526: cell width=17, height=37
info: fcft.c:451: /usr/share/fonts/TTF/TerminusTTF.ttf: size=12.50pt/13px, dpi=75
info: fcft.c:451: /usr/share/fonts/TTF/TerminusTTF-Bold.ttf: size=12.50pt/13px, dpi=75
info: fcft.c:451: /usr/share/fonts/TTF/TerminusTTF-Italic.ttf: size=12.50pt/13px, dpi=75
info: fcft.c:451: /usr/share/fonts/TTF/TerminusTTF-Bold Italic.ttf: size=12.50pt/13px, dpi=75
info: terminal.c:526: cell width=7, height=14
info: main.c:393: goodbye
nikp123@HP-Laptop /home/nikp123 $ 

How to reproduce: 1. Launch foot 2. Try to resize font with keyboard shortcut ctrl in combination with either + or - Expected behaviour: Font scales properly when trying to resize Issue in detail: The font doesn't get scaled linearly because when resizing foot doesn't read the DPI correctly Attached log - (describes the bug): ``` nikp123@HP-Laptop /home/nikp123 $ foot info: config.c:841: loading configuration from /home/nikp123/.config/footrc info: wayland.c:798: HDMI-A-1: 1920x1080+1092x0@60Hz 2343 23.10" scale=1 PPI=96x98 (physical) PPI=96x98 (logical) info: wayland.c:798: eDP-1: 1366x768+0x645@60Hz 0x0354 13.23" scale=2 PPI=124x128 (physical) PPI=99x102 (logical) info: wayland.c:834: cursor theme: (null), size: 24 info: terminal.c:482: using 4 rendering threads info: wayland.c:1027: requesting SSD decorations info: fcft.c:451: /usr/share/fonts/TTF/TerminusTTF.ttf: size=12.00pt/32px, dpi=196 info: fcft.c:451: /usr/share/fonts/TTF/TerminusTTF-Bold.ttf: size=12.00pt/32px, dpi=196 info: fcft.c:451: /usr/share/fonts/TTF/TerminusTTF-Italic.ttf: size=12.00pt/32px, dpi=196 info: fcft.c:451: /usr/share/fonts/TTF/TerminusTTF-Bold Italic.ttf: size=12.00pt/32px, dpi=196 info: terminal.c:526: cell width=16, height=35 info: wayland.c:634: using SSD decorations info: fcft.c:451: /usr/share/fonts/TTF/TerminusTTF.ttf: size=12.00pt/34px, dpi=204 info: fcft.c:451: /usr/share/fonts/TTF/TerminusTTF-Bold.ttf: size=12.00pt/34px, dpi=204 info: fcft.c:451: /usr/share/fonts/TTF/TerminusTTF-Italic.ttf: size=12.00pt/34px, dpi=204 info: fcft.c:451: /usr/share/fonts/TTF/TerminusTTF-Bold Italic.ttf: size=12.00pt/34px, dpi=204 info: terminal.c:526: cell width=17, height=37 info: fcft.c:451: /usr/share/fonts/TTF/TerminusTTF.ttf: size=12.50pt/13px, dpi=75 info: fcft.c:451: /usr/share/fonts/TTF/TerminusTTF-Bold.ttf: size=12.50pt/13px, dpi=75 info: fcft.c:451: /usr/share/fonts/TTF/TerminusTTF-Italic.ttf: size=12.50pt/13px, dpi=75 info: fcft.c:451: /usr/share/fonts/TTF/TerminusTTF-Bold Italic.ttf: size=12.50pt/13px, dpi=75 info: terminal.c:526: cell width=7, height=14 info: main.c:393: goodbye nikp123@HP-Laptop /home/nikp123 $ ```

dnkl commented 2020年03月14日 21:08:44 +01:00

Thanks!

I've been trying to reproduce this one for a while now, including installing and using the same font you're using, and using the same scale factor. Nothing mattered - it still worked for me.

Until I tried a typo in the font configuration: Terminus (TTF);size=12 instead of Terminus (TTF):size=12 (note the incorrect usage of a semicolon - the attributes should be colon separated).

So first of all I'd like you to check your footrc and the font configuration; make sure it's in the correct format.

Assuming this is the issue, I pushed a fix to the fcft library. You can either update your foot-git AUR package, or do a git pull in foot/subprojects/fcft.

If none of the above helps, I'd like you to apply this patch to foot/subprojects/fcft:

diff --git a/fcft.c b/fcft.c
index 96c2005..c198e70 100644
--- a/fcft.c
+++ b/fcft.c
@@ -650,6 +650,8 @@ pattern_from_font_with_adjusted_size(const struct font_priv *font, double amount
 
 setlocale(LC_ALL, cur_locale);
 free(cur_locale);
+ LOG_INFO("adjust: amount=%f, pattern \"%s\" -> \"%s\"",
+ amount, font->pattern, pattern);
 return pattern;
 }
 

Then recompile foot and run. You should see the new log message when you try to change the font size with e.g. ctrl-+.

Thanks! I've been trying to reproduce this one for a while now, including installing and using the same font you're using, and using the same scale factor. Nothing mattered - it still worked for me. Until I tried a typo in the font configuration: `Terminus (TTF);size=12` instead of `Terminus (TTF):size=12` (note the incorrect usage of a semicolon - the attributes should be colon separated). So first of all I'd like you to check your `footrc` and the font configuration; make sure it's in the correct format. Assuming this is the issue, I pushed a fix to the **fcft** library. You can either update your `foot-git` AUR package, or do a `git pull` in `foot/subprojects/fcft`. If none of the above helps, I'd like you to apply this patch to `foot/subprojects/fcft`: ```diff diff --git a/fcft.c b/fcft.c index 96c2005..c198e70 100644 --- a/fcft.c +++ b/fcft.c @@ -650,6 +650,8 @@ pattern_from_font_with_adjusted_size(const struct font_priv *font, double amount setlocale(LC_ALL, cur_locale); free(cur_locale); + LOG_INFO("adjust: amount=%f, pattern \"%s\" -> \"%s\"", + amount, font->pattern, pattern); return pattern; } ``` Then recompile foot and run. You should see the new log message when you try to change the font size with e.g. <kbd>ctrl</kbd>-<kbd>+</kbd>.

dnkl commented 2020年03月14日 21:10:33 +01:00

... and post the new log ;)

... and post the new log ;)

dnkl commented 2020年03月14日 21:12:35 +01:00

Assuming this is the issue, I pushed a fix to the fcft library.

Just to clarify: the fix ensures the DPI attribute isn't "lost". However, a typo in the font specification is still a typo...

> Assuming this is the issue, I pushed a fix to the fcft library. Just to clarify: the fix ensures the DPI attribute isn't "lost". However, a typo in the font specification is still a typo...

nikp123 commented 2020年03月14日 21:48:43 +01:00

@dnkl I used fontsize instead of size in footrc. Maybe that's the issue?

Also can confirm that by using size instead of fontsize everything works as expected.

@dnkl I used ``fontsize`` instead of ``size`` in footrc. Maybe that's the issue? Also can confirm that by using ``size`` instead of ``fontsize`` everything works as expected.

dnkl commented 2020年03月14日 21:57:24 +01:00

@nikp123 yup, that was the issue. Using an unpatched fcft, <font-name>:fontsize=12:dpi=154 was replaced with <font-name>:fontdpi=154.

@nikp123 yup, that was the issue. Using an unpatched fcft, `<font-name>:fontsize=12:dpi=154` was replaced with `<font-name>:fontdpi=154`.