Rebuild Iosevka Comfy (upstream v.11.2.7)

* Improve: the README to explain how Iosevka Comfy differs from the
  standard Iosevka style.

* Make the capital 'D' use a top and bottom serif to avoid the issue
  where TODO at small point sizes reads like TOOO.  This reverts commit
  3e3a91f.

* Use a single storey 'a' for roman and italic variants.  The rounded
  shape is more consistent with the rest of the typeface.

* Use a tailed 'u' for both variants, for the same reason as above.

* Revert to using an 'm' with a short middle leg to avoid the problem
  where the three legs visually blend into a solid block at small point
  sizes.  Roman and italic variants have slighty different 'm' glyphs
  due to their particular requirements, though both use the short middle
  leg style in the interest of consistency.

* Make the '0' have an oval shape for both roman and italic variants
  with a dashed forward slash which looks like a dot at small point
  sizes.  The slashed zero that was used before feels like an
  exaggeration when the oval shape of the character already is
  sufficiently distinct from 'O'.  This new style is better than the
  alternative of the dotted zero because the inside of the character is
  more subtle (again, avoiding the possible exaggeration).

* Other minor tweaks to the comments in the private-build-plans.toml.

README.md

@@ -1,20 +1,76 @@
 # Iosevka Comfy
 
-Private build of the Iosevka monospaced font, with adjusted metrics and
-lots of overrides for individual glyphs at both roman and italic
-variants.
+Private build of the Iosevka monospaced font, with a rounded style,
+adjusted metrics, and overrides for almost all individual glyphs in both
+roman (upright) and italic (slanted) variants.
 
-Configured in accordance with the documentation of the upstream project:
-<https://github.com/be5invis/Iosevka>.  Last update on 2021-09-08 using
-Iosevka version `v10.1.1` commit `9f26049`.
+Iosevka Comfy is wider and more vertically compact than the standard
+upstream configuration.  Glyphs are rounder and have tailed ends or
+serifs wherever that is required to both impose an aesthetic rhythm and
+keep characters distinct from each other.  Roman and italic variants are
+made to look more consistent while retaining their stylistic features
+(e.g. the italics do not have calligraphic tendencies but still use
+carefully selected glyphs that are distinct from the roman
+counterparts).
 
-The files are provided as-is in the hope that they may prove useful, but
-are otherwise intended only for my private use.
+The overall appearance of the typeface is optimised for small point
+sizes.  This informs the choice of certain glyphs such as `D` with a top
+and bottom serif and a curved body to clearly differentiate it from the
+capital `O`, or an `m` with a short middle leg to prevent the letter's
+lines from visually blending into a box-like shape (always referring to
+small point sizes).  For larger size, these details are not strictly
+necessary, though Iosevka Comfy should still look decent despite their
+presence.
+
+Considering the line height and width as well as the desired appearance
+of each glyph, the optimal point values are: 8, 10, 12, 13.  Other sizes
+which are almost as good: 9, 10.5, 13.5.
+
+[ For the `:height` face attribute in GNU Emacs, the value is equal to
+  the point size × 10. ]
+
+## Build information
+
+Iosevka Comfy is configured in accordance with the documentation of the
+upstream project: <https://github.com/be5invis/Iosevka>.  This
+practically means that we define our `private-build-plans.toml`, install
+the `npm` dependencies, and then build the `.ttf` files with the
+following command:
+
+```sh
+npm run build -- ttf::iosevka-comfy
+```
+
+The last update to Iosevka Comfy was done on 2022-01-25 using upstream
+Iosevka version `v11.2.7` at commit `f630c223`.
+
+Each file is provided as-is in the hope that it may prove useful, but
+is otherwise intended only for my private use.
+
+## Character sample and common patterns
+
+Note that for the sake of this demonstration, the point size is higher
+than the intended target range.
 
 ![iosevka-comfy-sample-light](./iosevka-comfy-sample-light.png)
 
-![iosevka-comfy-sample-dark](./iosevka-comfy-sample-dark.png)
+## Comparison to base Iosevka
 
-![iosevka-comfy-sample-light-large](./iosevka-comfy-sample-light-large.png)
+This is a regular Emacs session with the default font set to point size
+10 (a `:height` face attribute of 100).  Obverse, in particular, Iosevka
+Comfy's proportions (wider, shorter line height than Iosevka) and the
+less exaggerated differences between its roman and italic characters to
+make the latter look closer to their roman counterparts without
+detracting from their subtleties (e.g. for the italic variant of Iosevka
+Comfy the `f` is not cursive, the `y` is not so curvy, the descender of
+the `g` is not closed, while the `t`, `i`, `l` have short tails, etc.).
 
-![iosevka-comfy-sample-dark-large](./iosevka-comfy-sample-dark-large.png)
+![iosevka-comfy-10pt](./iosevka-comfy-10pt.png)
+
+![iosevka-10pt](./iosevka-10pt.png)
+
+For Iosevka Comfy to have roughly the same line width as Iosevka, it has
+to be set at one point less.  It still has a more compact line height.
+Compare the following screenshot to the one above:
+
+![iosevka-comfy-9pt](./iosevka-comfy-9pt.png)

private-build-plans.toml

@@ -15,7 +15,7 @@ serifs = "sans"                  # Optional; Values: `sans` or `slab`
 cv01 = 1    # A cap straight
 cv02 = 1    # B cap straight
 cv03 = 1    # C cap serifless
-cv04 = 4    # D cap curly with top serif
+cv04 = 6    # D cap curly with top and bottom serif (without serifs TODO reads like TOOO at small point sizes)
 cv05 = 1    # E cap serifless
 cv06 = 1    # F cap serifless
 cv07 = 4    # G cap toothed
@@ -37,6 +37,7 @@ cv22 = 1    # W straight
 cv23 = 1    # X cap straight
 cv24 = 1    # Y cap straight
 cv25 = 1    # Z cap straight
+cv26 = 10   # a single storey earless tailed bottom
 cv27 = 1    # b toothed
 cv28 = 1    # c serifless
 cv29 = 1    # d toothed
@@ -47,12 +48,14 @@ cv37 = 10   # l serified flat tailed
 cv42 = 9    # r compact
 cv43 = 1    # s serifless
 cv44 = 2    # t flat hook
+cv45 = 4    # u tailed
 cv49 = 6    # y cursive flat terminal hook
-cv53 = 1    # Λ lambda cap straight
+cv53 = 1    # Λ, Δ lambda and delta cap straight
 cv54 = 2    # α alpha straight tailed
-cv55 = 1    # γ gamma cap straight
+cv55 = 1    # Γ gamma cap straight
 cv56 = 6    # ι iota serified flat tailed
 cv57 = 2    # λ lambda top tailed
+cv71 = 13   # 0 oval dashed forward slash
 cv74 = 2    # 3 arched
 cv76 = 2    # 5 open contour
 cv78 = 1    # 7 straight
@@ -76,21 +79,18 @@ cv99 = 1    # .:; circular punctuation marks
 
 # Optional; Configure single character's variant for Upright and Oblique; Overrides [design]
 [buildPlans.iosevka-comfy.variants.upright]
-cv26 = 1    # a double storey
 cv30 = 1    # e straight
 cv31 = 16   # f serifless bottom flat top crossbar at x height
 cv32 = 9    # g single storey flat hook earless cornered top
 cv36 = 1    # k straight
-cv38 = 9    # m earless double arch
+cv38 = 6    # m earless double arch short middle leg
 cv39 = 3    # n earless straight
 cv40 = 2    # p earless
 cv41 = 2    # q earless
-cv45 = 1    # u straight
 cv46 = 1    # v straight
 cv47 = 1    # w straight
 cv48 = 1    # x straight
 cv50 = 1    # z straight
-cv71 = 7    # 0 oval slashed
 cv72 = 2    # 1 serified with base
 cv73 = 1    # 2 straight
 cv75 = 3    # 4 semi-open contour
@@ -101,7 +101,6 @@ cv90 = 1    # @ at threefold
 
 # Optional; Configure single character's variant for Italic only; Overrides [design]
 [buildPlans.iosevka-comfy.variants.italic]
-cv26 = 10   # a single storey earless tailed
 cv30 = 2    # e curly
 cv31 = 14   # f extended flat top bottom hook
 cv32 = 7    # g single storey flat hook
@@ -110,12 +109,10 @@ cv38 = 2    # m straight middle shortleg
 cv39 = 1    # n straight
 cv40 = 1    # p straight
 cv41 = 1    # q straight
-cv45 = 4    # u tailed
 cv46 = 2    # v curly
 cv47 = 2    # w curly short middle top
 cv48 = 2    # x curly
 cv50 = 4    # z curly
-cv71 = 2    # 0 slashed
 cv72 = 1    # 1 serified no base
 cv73 = 2    # 2 curly
 cv75 = 1    # 4 closed contour crossing