[Freefont-bugs] a comparison of FreeMono.ttf versions of 2003-06-24 and 2008-03-24

[Joe Wells]

To compare the latest FreeMono.ttf with earlier versions, I have run
the command

  xterm -title FreeMono-8 -geometry 130x32+0+0 -fa FreeMono-8 +fbx -e sh -c 
"echo ${ESC}%GFreeMono-8; head -n 30 UTF-8-font-test-sample.txt; sleep 99999"

with the versions of FreeMono.ttf of 2008-03-24 (latest release) and
2003-06-24 (five years ago).  (The variable ESC holds a string of
length 1 whose sole character is the escape character.)

I was running on a LCD with (I believe) rgb subpixel order with
subpixel aliasing turned on.

Screenshots are attached below, as is the sample text file I used.

Here are some quick observations:

• More characters are included.  Hurray!

• Hinting is a bit nicer in the latest fonts.  I can see many
  individual characters (like I, N, 1, 4, etc.) that have better
  subpixel aliasing and come out looking black instead of colored.

  I'm pleased to see this progress and I think the maintainers deserve
  congratulations.

• There are still plenty of characters that get bad subpixel aliasing
  and therefore show up with colored fringes.  Examples include ℝ, ░,
  ⊪, etc.  I guess there is lots of work to do here with hinting.
  (Can the autohinter handle these decently?)

• The vertical spacing is screwed up (at least in xterm).  This causes
  two problems:

  ‣ Each line takes up too much vertical space, so fewer lines can be
    displayed, which is a big problem on short screens.

  ‣ Characters that are supposed to combine vertically like “⎪”
    (U+23AA, CURLY BRACKET EXTENSION) have gaps between them.

  This problem does not occur in the font as of 5 years ago, as you
  can see for yourself in the screenshot.  (I think the problems in
  the older screenshot are caused by xterm drawing the line-drawing
  characters instead of using what is in the font.)

  By itself, this is a big enough reason to keep using the old font.
  The number of lines that will fit on a screen is a primary criteria
  used when selecting a font for terminal windows, and the ability to
  display line drawings correctly is also very significant.  For the
  same reason, I have previously refused to upgrade to FreeFont.ttf
  versions of 2003-10-08 and 2006-01-26.  Due to this problem, right
  now upgrading would actually be a downgrade.

• The older glyphs for the quote characters (i.e., ‘, “, ”, ’) are
  much nicer for a screen font.  It would be nice to be able to get
  the old glyphs somehow.

• Something awful is happening with combining accents.  You can see in
  the screenshot in the test line “STARGΛ̊TE SG-1, a = v̇ = r̈, a⃑ ⊥ b⃑”
  that the combining accents (when they are drawn at all) are all
  positioned one character cell to the left of where they should be.
  This was working in the font as of 5 years ago, so presumably this
  is a bug introduced since then.

For what it is worth, I am running Ubuntu 6.06 LTS (“Dapper Drake”)
and I think all packages involved in this test are the latest
available for Ubuntu 6.06.

I hope this report is helpful.

Joe Wells

----------------------------------------------------------------------

Screenshot for FreeMono.ttf dated 2003-06-24:



-- 
Heriot-Watt University is a Scottish charity
registered under charity number SC000278

----------------------------------------------------------------------

Screenshot for FreeMono.ttf dated 2008-03-24:

----------------------------------------------------------------------

Sample text file used in tests:

  ABCDEFGHIJKLMNOPQRSTUVWXYZ /0123456789  –—‘“”„†•…‰™œŠŸž€ ΑΒΓΔΩαβγδω АБВГДабвгд
  abcdefghijklmnopqrstuvwxyz £©µÀÆÖÞßéöÿ  ∀∂∈ℝ∧∪≡∞ ↑↗↨↻⇣ ┐┼╔╘░►☺♀ fi�⑀₂ἠḂӥẄɐː⍎אԱა
  
ö∧∅∪∩∈∉∃≲⋠↖≾≊⊟⋎⋧⊸∖⊏⋩ℵ⋍≐≳ℷ⋚≰⋦≇≮⊀∴♯⋏⇍≲⊓⊎⊑⇛∍⋞⋜⋐⊪↛⋁⋈ℸ≓↩↼↫⋒≦≱≯⊴≼≁≺⋆≼≽≔⇝⇉↞∔↝⋖↭⩀⨄⩃⩃⩄⩍⫙⫛⩴﹨,
 ,‌,
,

  ╔══╦══╗  ┌──┬──┐  ╭──┬──╮  ╭──┬──╮  ┏━━┳━━┓  ┎┒┏┑   ╷  ╻ ┏┯┓ ┌┰┐    █ ╱╲╱╲╳╳╳
  ║┌─╨─┐║  │╔═╧═╗│  │╒═╪═╕│  │╓─╁─╖│  ┃┌─╂─┐┃  ┗╃╄┙  ╶┼╴╺╋╸┠┼┨ ┝╋┥    ▉ ╲╱╲╱╳╳╳
  ║│╲ ╱│║  │║   ║│  ││ │ ││  │║ ┃ ║│  ┃│ ╿ │┃  ┍╅╆┓   ╵  ╹ ┗┷┛ └┸┘    ▊ ╱╲╱╲╳╳╳
  ╠╡ ╳ ╞╣  ├╢   ╟┤  ├┼─┼─┼┤  ├╫─╂─╫┤  ┣┿╾┼╼┿┫  ┕┛┖┚     ┌┄┄┐ ╎ ┏┅┅┓ ┋ ▋ ╲╱╲╱╳╳╳
  ║│╱ ╲│║  │║   ║│  ││ │ ││  │║ ┃ ║│  ┃│ ╽ │┃  ░░▒▒▓▓██ ┊  ┆ ╎ ╏  ┇ ┋ ▌
  ║└─╥─┘║  │╚═╤═╝│  │╘═╪═╛│  │╙─╀─╜│  ┃└─╂─┘┃  ░░▒▒▓▓██ ┊  ┆ ╎ ╏  ┇ ┋ ▍
  ╚══╩══╝  └──┴──┘  ╰──┴──╯  ╰──┴──╯  ┗━━┻━━┛  ▗▄▖▛▀▜   └╌╌┘ ╎ ┗╍╍┛ ┋ ▎▁▂▃▄▅▆▇█
                                               ▝▀▘▙▄▟                 ▏
  ∮ E⋅da = Q,  n → ∞, ∑ f(i) = ∏ g(i),      ⎧⎡⎛┌─────┐⎞⎤⎫  
≲,≳,≾,⋩,⋦,⋧,⪹,⪺,⪳,⪴,⪵,⪶,⪻,⪼,⪱,⪲,≊,⋍,≁,≇,∴,♯,ö,∧,∅,∪,∩,∃,↖,⊟,⊸,∖,ℵ,ℷ
  ∀x∈ℝ: ⌈x⌉ = −⌊−x⌋, α ∧ ¬β = ¬(¬α ∨ β),    ⎪⎢⎜│a²+b³ ⎟⎥⎪  
≺,⊀,⩽,⋞,⋜,≦,≮,≯,⊴,⊏,⊑,⫒,⫑,⋐,⋒,≐,≓,⇍,⇛,↛,↩,↼,↫,⋏,⋎,⊓,⊎,⊪,⋁,⋈,ℸ,⋆
  ℕ ⊆ ℕ₀ ⊂ ℤ ⊂ ℚ ⊂ ℝ ⊂ ℂ,                   ⎪⎢⎜│───── ⎟⎥⎪  
≼,≽,⋠,⋖,⩿,⪯,⪰,⋚,≰,≱,⇝,⇉,↞,↝,↭,∔,⩀,⨄,⩃,⩄,⩍,⫙,⫛,≔,⩴,‌,
, , ,

  ⊥ < a ≠ b ≡ c ≤ d ≪ ⊤ ⇒ (⟦A⟧ ⇔ ⟪B⟫),      ⎪⎢⎜⎷ c₈   ⎟⎥⎪  
⦅,⦆,〘,〙,⦑,⦒,⦉,⦊,⦃,⦄,⦇,⦈,⟅,⟆,⟦,⟧,⟨,⟩,⟪,⟫,⟂,Ⓢ,✉,⤺
  2H₂ + O₂ ⇌ 2H₂O, R = 4.7 kΩ, ⌀ 200 mm     ⎨⎢⎜       ⎟⎥⎬  
∈,∉,∍,⋶,⋽,⟵,⟶,⟷,⟸,⟹,⟺,⟼,′,⁗,ⁱ,⟡,﹨,⧋,⩞,Ⓟ,⤼,⦶,⧲,ₐ,ₑ,ₒ,ₓ,ₔ
  ði ıntəˈnæʃənəl fəˈnɛtık əsoʊsiˈeıʃn      ⎪⎢⎜ ∞     ⎟⎥⎪  
⧹,⧆,⧈,⧅,⧇,⧄,⨟,⨾,⫴,⦀,⫼,⪦,⩕,⦵,⦸,⧁,⧀,⪧,⫽,⫿,⫾,⦾,⨪,⩎,⩏,⨰,⨢,⩣,⦺,⨸
  Y [ˈʏpsilɔn], Yen [jɛn], Yoga [ˈjoːgɑ]    ⎪⎢⎜ ⎲     ⎟⎥⎪  
⫫,⧟,⥼,⥽,⟜,⤀,⩦,⫥,⫤,⤆,⤇,⚡,⤻,⥫,⥭,⥢,⥤,⥥,⥊,⥮,⥬,⥯,⥣,⥪,⥋,㏚,ȷ,⟐,⧣,℻
  ((V⍳V)=⍳⍴V)/V←,V    ⌷←⍳→⍴∆∇⊃‾⍎⍕⌈          ⎪⎢⎜ ⎳aⁱ-bⁱ⎟⎥⎪  
ᵪ,ᵩ,ᵨ,ᵧ,ᵦ,ᵥ,ᵤ,ᵣ,ᵢ,ᵡ,ᵠ,ᵟ,ᵞ,ᵝ,ᵛ,ᵚ,ᵙ,ᵘ,ᵗ,ᵖ,ᵕ,ᵔ,ᵓ,ᵒ,ᵑ,ᵐ,ᵏ,ᵎ,ᵍ,ᵊ,ᵉ,ᵈ,ᵇ,ᵆ,ᵅ,ᵃ
  ║   • ‘single’ and “double” quotes        ⎩⎣⎝i=1    ⎠⎦⎭  
ᵂ,ᵁ,ᵀ,ᴿ,ᴾ,ᴽ,ᴼ,ᴻ,ᴺ,ᴹ,ᴸ,ᴷ,ᴶ,ᴵ,ᴴ,ᴳ,ᴲ,ᴱ,ᴰ,ᴮ,ᴯ,ᴭ,ᴬ,∗,∘,⊕,⊖,⊗,⊘,⊙,⊚,⊛,⊜,⊝,⊞,⊟,⊠,⊡
  ║   • Curly apostrophes: “We’ve been here” ║             
ⓩ,ⓨ,ⓧ,ⓦ,ⓥ,ⓤ,ⓣ,ⓢ,ⓡ,ⓠ,ⓟ,ⓞ,ⓝ,ⓜ,ⓛ,ⓚ,ⓙ,ⓘ,ⓗ,ⓖ,ⓕ,ⓔ,ⓓ,ⓒ,ⓑ,ⓐ
  ║   • Latin-1 apostrophe and accents: '´`  ║             
Ⓩ,Ⓨ,Ⓧ,Ⓦ,Ⓥ,Ⓤ,Ⓣ,Ⓡ,Ⓠ,Ⓞ,Ⓝ,Ⓜ,Ⓛ,Ⓚ,Ⓙ,Ⓘ,Ⓗ,Ⓖ,Ⓕ,Ⓔ,Ⓓ,Ⓒ,Ⓑ
  ║   • ‚deutsche‘ „Anführungszeichen“       ║             
⒵,⒴,⒳,⒲,⒱,⒰,⒯,⒮,⒭,⒬,⒫,⒪,⒩,⒨,⒧,⒦,⒥,⒤,⒣,⒢,⒡,⒠,⒟,⒞,⒝
  ║   • †, ‡, ‰, •, 3–4, —, −5/+5, ™, …      ║             
⒛,⒚,⒙,⒘,⒗,⒖,⒕,⒔,⒓,⒒,⒑,⒐,⒏,⒎,⒍,⒌,⒋,⒉,⒊,⒇
  ║   • ASCII safety test: 1lI|, 0OD, 8B     ║
  ║                      ╭─────────╮         ║
  ║   • the euro symbol: │ 14.95 € │         ║
  ║                      ╰─────────╯         ║
  STARGΛ̊TE SG-1, a = v̇ = r̈, a⃑ ⊥ b⃑
UTF-8 encoded sample plain-text file from another file by Markus Kuhn [ˈmaʳkʊs 
kuːn]
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