Rollup merge of #90232 - konan8205:master, r=GuillaumeGomez

rustdoc: Use TTF based font instead of OTF for CJK glyphs to improve readability

Due to Windows' implementation of font rendering, OpenType fonts can be distorted. So the existing font, Noto Sans KR, is not very readable on Windows. This PR improves readability of Korean glyphs on Windows.

## Before
![원1](https://user-images.githubusercontent.com/11029378/138592394-16b15787-532d-4421-a5eb-ed85675290fa.png)

## After
![원2](https://user-images.githubusercontent.com/11029378/138592409-f3a440ee-f0fc-40e4-9561-42c479439c9f.png)

The fonts included in this PR are licensed under the SIL Open Font License and generated with these commands:

```sh
pyftsubset NanumBarunGothic.ttf \
--unicodes=U+AC00-D7AF,U+1100-11FF,U+3130-318F,U+A960-A97F,U+D7B0-D7FF \
--output-file=NanumBarunGothic.ttf.woff --flavor=woff
```
```sh
pyftsubset NanumBarunGothic.ttf \
--unicodes=U+AC00-D7AF,U+1100-11FF,U+3130-318F,U+A960-A97F,U+D7B0-D7FF \
--output-file=NanumBarunGothic.ttf.woff2 --flavor=woff2
```

r? ``@GuillaumeGomez``

src/librustdoc/html/render/write_shared.rs

@@ -39,9 +39,9 @@ static FILES_UNVERSIONED: Lazy<FxHashMap<&str, &[u8]>> = Lazy::new(|| {
         "SourceCodePro-Semibold.ttf.woff" => static_files::source_code_pro::SEMIBOLD,
         "SourceCodePro-It.ttf.woff" => static_files::source_code_pro::ITALIC,
         "SourceCodePro-LICENSE.txt" => static_files::source_code_pro::LICENSE,
-        "noto-sans-kr-regular.woff2" => static_files::noto_sans_kr::REGULAR2,
-        "noto-sans-kr-regular.woff" => static_files::noto_sans_kr::REGULAR,
-        "noto-sans-kr-LICENSE.txt" => static_files::noto_sans_kr::LICENSE,
+        "NanumBarunGothic.ttf.woff2" => static_files::nanum_barun_gothic::REGULAR2,
+        "NanumBarunGothic.ttf.woff" => static_files::nanum_barun_gothic::REGULAR,
+        "NanumBarunGothic-LICENSE.txt" => static_files::nanum_barun_gothic::LICENSE,
         "LICENSE-MIT.txt" => static_files::LICENSE_MIT,
         "LICENSE-APACHE.txt" => static_files::LICENSE_APACHE,
         "COPYRIGHT.txt" => static_files::COPYRIGHT,

src/librustdoc/html/static/css/rustdoc.css

@@ -77,11 +77,11 @@
 
 /* Avoid using legacy CJK serif fonts in Windows like Batang. */
 @font-face {
-	font-family: 'Noto Sans KR';
-	src: url("noto-sans-kr-regular.woff2") format("woff2"),
-		url("noto-sans-kr-regular.woff") format("woff");
+	font-family: 'NanumBarunGothic';
+	src: url("NanumBarunGothic.ttf.woff2") format("woff2"),
+		url("NanumBarunGothic.ttf.woff") format("woff");
 	font-display: swap;
-	unicode-range: U+AC00-D7AF, U+3130-318F, U+1100-11FF, U+A960-A97F, U+D7B0-D7FF;
+	unicode-range: U+AC00-D7AF, U+1100-11FF, U+3130-318F, U+A960-A97F, U+D7B0-D7FF;
 }
 
 * {
@@ -108,7 +108,7 @@ html {
 /* General structure and fonts */
 
 body {
-	font: 16px/1.4 "Source Serif 4", "Noto Sans KR", serif;
+	font: 16px/1.4 "Source Serif 4", NanumBarunGothic, serif;
 	margin: 0;
 	position: relative;
 	padding: 10px 15px 20px 15px;
@@ -196,7 +196,7 @@ div.impl-items > div:not(.docblock):not(.item-info),
 .content ul.crate a.crate, a.srclink,
 /* This selector is for the items listed in the "all items" page. */
 #main > ul.docblock > li > a {
-	font-family: "Fira Sans", Arial, sans-serif;
+	font-family: "Fira Sans", Arial, NanumBarunGothic, sans-serif;
 }
 
 .content ul.crate a.crate {

src/librustdoc/html/static/fonts/noto-sans-kr-LICENSE.txt → src/librustdoc/html/static/fonts/NanumBarunGothic-LICENSE.txt

@@ -1,8 +1,14 @@
-Copyright 2014, 2015 Adobe Systems Incorporated (http://www.adobe.com/), with Reserved Font Name 'Source'. All Rights Reserved. Source is a trademark of Adobe Systems Incorporated in the United States and/or other countries.
+Copyright (c) 2010, NAVER Corporation (https://www.navercorp.com/),
 
-This Font Software is licensed under the SIL Open Font License, Version 1.1.
+with Reserved Font Name Nanum, Naver Nanum, NanumGothic, Naver NanumGothic,
+NanumMyeongjo, Naver NanumMyeongjo, NanumBrush, Naver NanumBrush, NanumPen,
+Naver NanumPen, Naver NanumGothicEco, NanumGothicEco, Naver NanumMyeongjoEco,
+NanumMyeongjoEco, Naver NanumGothicLight, NanumGothicLight, NanumBarunGothic,
+Naver NanumBarunGothic, NanumSquareRound, NanumBarunPen, MaruBuri
 
-This license is copied below, and is also available with a FAQ at: http://scripts.sil.org/OFL
+This Font Software is licensed under the SIL Open Font License, Version 1.1.
+This license is copied below, and is also available with a FAQ at:
+http://scripts.sil.org/OFL
 
 
 -----------------------------------------------------------

src/librustdoc/html/static_files.rs

@@ -160,15 +160,35 @@ crate mod source_code_pro {
     crate static LICENSE: &[u8] = include_bytes!("static/fonts/SourceCodePro-LICENSE.txt");
 }
 
-crate mod noto_sans_kr {
-    /// The file `noto-sans-kr.woff`, the Regular variant of the Noto Sans KR font.
-    crate static REGULAR: &[u8] = include_bytes!("static/fonts/noto-sans-kr-regular.woff");
-
-    /// The file `noto-sans-kr.woff2`, the Regular variant of the Noto Sans KR font.
-    crate static REGULAR2: &[u8] = include_bytes!("static/fonts/noto-sans-kr-regular.woff2");
-
-    /// The file `noto-sans-kr-LICENSE.txt`, the license text of the Noto Sans KR font.
-    crate static LICENSE: &[u8] = include_bytes!("static/fonts/noto-sans-kr-LICENSE.txt");
+/// Files related to the Nanum Barun Gothic font.
+///
+/// These files are used to avoid some legacy CJK serif fonts in Windows.
+///
+/// Note that the Noto Sans KR font, which was used previously but was not very readable on Windows,
+/// has been replaced by the Nanum Barun Gothic font. This is due to Windows' implementation of font
+/// rendering that distorts OpenType fonts too much.
+///
+/// The font files were generated with these commands:
+///
+/// ```sh
+/// pyftsubset NanumBarunGothic.ttf \
+/// --unicodes=U+AC00-D7AF,U+1100-11FF,U+3130-318F,U+A960-A97F,U+D7B0-D7FF \
+/// --output-file=NanumBarunGothic.ttf.woff --flavor=woff
+/// ```
+/// ```sh
+/// pyftsubset NanumBarunGothic.ttf \
+/// --unicodes=U+AC00-D7AF,U+1100-11FF,U+3130-318F,U+A960-A97F,U+D7B0-D7FF \
+/// --output-file=NanumBarunGothic.ttf.woff2 --flavor=woff2
+/// ```
+crate mod nanum_barun_gothic {
+    /// The file `NanumBarunGothic.ttf.woff`, the Regular variant of the Nanum Barun Gothic font.
+    crate static REGULAR: &[u8] = include_bytes!("static/fonts/NanumBarunGothic.ttf.woff");
+
+    /// The file `NanumBarunGothic.ttf.woff2`, the Regular variant of the Nanum Barun Gothic font.
+    crate static REGULAR2: &[u8] = include_bytes!("static/fonts/NanumBarunGothic.ttf.woff2");
+
+    /// The file `NanumBarunGothic-LICENSE.txt`, the license text of the Nanum Barun Gothic font.
+    crate static LICENSE: &[u8] = include_bytes!("static/fonts/NanumBarunGothic-LICENSE.txt");
 }
 
 /// Files related to the sidebar in rustdoc sources.

src/test/rustdoc-gui/module-items-font.goml

@@ -1,23 +1,23 @@
 // This test checks that the correct font is used on module items (in index.html pages).
 goto: file://|DOC_PATH|/test_docs/index.html
-assert-css: (".item-table .module-item a", {"font-family": '"Fira Sans", Arial, sans-serif'}, ALL)
-assert-css: (".item-table .docblock-short", {"font-family": '"Source Serif 4", "Noto Sans KR", serif'}, ALL)
+assert-css: (".item-table .module-item a", {"font-family": '"Fira Sans", Arial, NanumBarunGothic, sans-serif'}, ALL)
+assert-css: (".item-table .docblock-short", {"font-family": '"Source Serif 4", NanumBarunGothic, serif'}, ALL)
 
 // modules
-assert-css: ("#modules + .item-table .item-left a", {"font-family": '"Fira Sans", Arial, sans-serif'})
-assert-css: ("#modules + .item-table .item-right.docblock-short", {"font-family": '"Source Serif 4", "Noto Sans KR", serif'})
+assert-css: ("#modules + .item-table .item-left a", {"font-family": '"Fira Sans", Arial, NanumBarunGothic, sans-serif'})
+assert-css: ("#modules + .item-table .item-right.docblock-short", {"font-family": '"Source Serif 4", NanumBarunGothic, serif'})
 // structs
-assert-css: ("#structs + .item-table .item-left a", {"font-family": '"Fira Sans", Arial, sans-serif'})
-assert-css: ("#structs + .item-table .item-right.docblock-short", {"font-family": '"Source Serif 4", "Noto Sans KR", serif'})
+assert-css: ("#structs + .item-table .item-left a", {"font-family": '"Fira Sans", Arial, NanumBarunGothic, sans-serif'})
+assert-css: ("#structs + .item-table .item-right.docblock-short", {"font-family": '"Source Serif 4", NanumBarunGothic, serif'})
 // enums
-assert-css: ("#enums + .item-table .item-left a", {"font-family": '"Fira Sans", Arial, sans-serif'})
-assert-css: ("#enums + .item-table .item-right.docblock-short", {"font-family": '"Source Serif 4", "Noto Sans KR", serif'})
+assert-css: ("#enums + .item-table .item-left a", {"font-family": '"Fira Sans", Arial, NanumBarunGothic, sans-serif'})
+assert-css: ("#enums + .item-table .item-right.docblock-short", {"font-family": '"Source Serif 4", NanumBarunGothic, serif'})
 // traits
-assert-css: ("#traits + .item-table .item-left a", {"font-family": '"Fira Sans", Arial, sans-serif'})
-assert-css: ("#traits + .item-table .item-right.docblock-short", {"font-family": '"Source Serif 4", "Noto Sans KR", serif'})
+assert-css: ("#traits + .item-table .item-left a", {"font-family": '"Fira Sans", Arial, NanumBarunGothic, sans-serif'})
+assert-css: ("#traits + .item-table .item-right.docblock-short", {"font-family": '"Source Serif 4", NanumBarunGothic, serif'})
 // functions
-assert-css: ("#functions + .item-table .item-left a", {"font-family": '"Fira Sans", Arial, sans-serif'})
-assert-css: ("#functions + .item-table .item-right.docblock-short", {"font-family": '"Source Serif 4", "Noto Sans KR", serif'})
+assert-css: ("#functions + .item-table .item-left a", {"font-family": '"Fira Sans", Arial, NanumBarunGothic, sans-serif'})
+assert-css: ("#functions + .item-table .item-right.docblock-short", {"font-family": '"Source Serif 4", NanumBarunGothic, serif'})
 // keywords
-assert-css: ("#keywords + .item-table .item-left a", {"font-family": '"Fira Sans", Arial, sans-serif'})
-assert-css: ("#keywords + .item-table .item-right.docblock-short", {"font-family": '"Source Serif 4", "Noto Sans KR", serif'})
+assert-css: ("#keywords + .item-table .item-left a", {"font-family": '"Fira Sans", Arial, NanumBarunGothic, sans-serif'})
+assert-css: ("#keywords + .item-table .item-right.docblock-short", {"font-family": '"Source Serif 4", NanumBarunGothic, serif'})