[css-color-5] Preserve hsl/hwb identity when result contains none w3c/csswg-drafts@99104cd

Author: triple-underscore

css-color5-ja.html

@@ -490,6 +490,7 @@
 
 § ~color_t 値の解決-法:~CSSCOLOR#resolving-color-values
 § ~color_t 値の直列化-法:~CSSCOLOR#serializing-color-values
+§ 欠落~成分との補間-法:~CSSCOLOR#interpolation-missing
 
 色停:~CSSIMAGE#color-stop
 生来な~size:~CSSIMAGE#natural-size
@@ -858,6 +859,7 @@
 	1 個の~spaceで連結-:singly-space-separated
 文字大小比較:case-insensitively:~
 hex:16 進
+発-:emit:~
 
 	尾部を成す:trailing
 	最初の引数:start of the function
@@ -987,6 +989,8 @@
 推定:inferring:~
 合格-:pass:~
 	合格しない:fail
+識別情報:identity:~
+降格-:degrade:~
 
 	単に:merely
 	他にも:besides
@@ -1067,6 +1071,8 @@
 	~~遺物:leftover
 	戻る~link:backlink
 	勧告候補の期間:CR period
+	失われ:lose
+	並行する:parallel
 
 	●未分類
 component::::コンポーネント
@@ -1132,6 +1138,7 @@
 	跳ね上が:shot up
 	持ち込:bring
 	得られ／得る:yield
+	結果は:yielding
 	総数:total number of
 	視覚-化-:visualize
 	視覚-化:visualization
@@ -1141,7 +1148,6 @@
 	かすかに:barely
 	通過-:pass through
 	渡-:pass
-	得る:yield
 	逆向きに:in reverse
 	ときにはある:sometimes
 	かけ離れる:very far from
@@ -1786,7 +1792,7 @@ <h3 title="Calculating the Result of color-mix">3.3. `color-mix^f の結果の
 • Let item stack be a stack made by reversing items. (Thus, with the first item at the top of the stack.)
 • While item stack has length 2 or greater:
 •• Pop from item stack twice, letting a and b be the two results in order. Let combined percentage be the sum of a and b’s percentages.
-•• Interpolate a and b’s colors as described in CSS Color 4 § 12. Color Interpolation, with a progress percentage equal to (b’s percentage) / combined percentage). If the specified color space is a cylindrical polar color space, then the &lt;hue-interpolation-method&gt; controls the interpolation of hue, as described in CSS Color 4 § 12.4 Hue Interpolation. If no &lt;hue-interpolation-method&gt; is specified, assume shorter.
+•• Interpolate a and b’s colors as described in CSS Color 4 § 13. Color Interpolation, with a progress percentage equal to (b’s percentage) / combined percentage). If the specified color space is a cylindrical polar color space, then the &lt;hue-interpolation-method&gt; controls the interpolation of hue, as described in CSS Color 4 § 13.4 Hue Interpolation. If no &lt;hue-interpolation-method&gt; is specified, assume shorter.
 •• Create a new mix item with the resulting color and a percentage of combined percentage, and push it onto item stack.
 • Set color to the color of the sole remaining item in item stack.
 </li>
@@ -2872,12 +2878,12 @@ <h3 title="Processing Model for Relative Colors ">4.1. 相対~色~用の処理~m
 
 <p>
 `欠落~成分$は、
-`~level 4$ の `§ 欠落~成分との補間-法＠~CSSCOLOR#interpolation-missing$
+`~level 4$ の `§ 欠落~成分との補間-法$
 と同じ仕方で取扱われる。
 `起点~色$の`欠落~成分$は、
 `相対~色~関数$の色~空間のある成分と`相似的な成分$であるならば，`先へ運ばれ$ることになる。
 ◎
-Missing components are handled the same way as with CSS Color 4 § 12.2 Interpolating with Missing Components: the origin colorspace and the relative function colorspace are checked for analogous components which are then carried forward as missing.
+Missing components are handled the same way as with CSS Color 4 § 13.2 Interpolating with Missing Components: the origin colorspace and the relative function colorspace are checked for analogous components which are then carried forward as missing.
 </p>
 
 <p>
@@ -6231,7 +6237,7 @@ <h3 title="Color Space for Interpolation">9.1. 補間~用の色~空間</h3>
 にて定義される `color-interpolation-method$t は、
 次のとおり，`~custom色~空間$の利用を許容するよう拡張される：
 ◎
-The &lt;color-interpolation-method&gt;, as defined in CSS Color 4 § 12.1 Color Space for Interpolation, is extended to allow use of the custom color spaces:
+The &lt;color-interpolation-method&gt;, as defined in CSS Color 4 § 13.1 Color Space for Interpolation, is extended to allow use of the custom color spaces:
 </p>
 
 <pre class="prod">
@@ -6292,7 +6298,7 @@ <h3 title="Resolving color-mix() Values">10.1. `color-mix^f 値の解決-法</h3
 `~level 4$ の `§ ~color_t 値の解決-法$
 ］に則って解決した結果になる。
 ◎
-If all &lt;color&gt; parameters resolve to the corresponding colors in their respective color spaces, the computed value is the mixed color, in the specified mixing color space, resolved according to CSS Color 4 § 14. Resolving &lt;color&gt; Values.＼
+If all &lt;color&gt; parameters resolve to the corresponding colors in their respective color spaces, the computed value is the mixed color, in the specified mixing color space, resolved according to CSS Color 4 § 15. Resolving &lt;color&gt; Values.＼
 </li>
 	<li>
 他の場合（ある~parameterに `currentcolor$v が利用された場合）
@@ -6303,7 +6309,7 @@ <h3 title="Resolving color-mix() Values">10.1. `color-mix^f 値の解決-法</h3
 関数はそのままなので、
 子~要素の中への継承を保全する。
 ◎
-Otherwise (if currentColor was used in the function), the computed value is the color-mix() function with each &lt;color&gt; parameter resolved according to CSS Color 4 § 14. Resolving &lt;color&gt; Values, thus preserving inheritance into child elements.
+Otherwise (if currentColor was used in the function), the computed value is the color-mix() function with each &lt;color&gt; parameter resolved according to CSS Color 4 § 15. Resolving &lt;color&gt; Values, thus preserving inheritance into child elements.
 </li>
 </ul>
 
@@ -6325,7 +6331,7 @@ <h3 title="Resolving Relative Color Syntax Values">10.2. 相対~色~構文によ
 関数~名で指示される【！specified RCS】色~空間
 ］内の絶対的な `color$t 値に解決した結果になる。
 ◎
-If all &lt;color&gt; parameters resolve to the corresponding colors in their respective color spaces, the computed value is the absolute &lt;color&gt; value, in the specified RCS color space, resolved according to CSS Color 4 § 14. Resolving &lt;color&gt; Values.
+If all &lt;color&gt; parameters resolve to the corresponding colors in their respective color spaces, the computed value is the absolute &lt;color&gt; value, in the specified RCS color space, resolved according to CSS Color 4 § 15. Resolving &lt;color&gt; Values.
 </li>
 	<li>
 他の場合（ある~parameterに `currentcolor$v が利用された場合）
@@ -6336,7 +6342,7 @@ <h3 title="Resolving Relative Color Syntax Values">10.2. 相対~色~構文によ
 関数はそのままなので、
 子~要素の中への継承を保全する。
 ◎
-Otherwise (if currentColor was used in the function), the computed value is the Relative Color Syntax function with the origin &lt;color&gt; parameter resolved according to CSS Color 4 § 14. Resolving &lt;color&gt; Values, thus preserving inheritance into child elements.
+Otherwise (if currentColor was used in the function), the computed value is the Relative Color Syntax function with the origin &lt;color&gt; parameter resolved according to CSS Color 4 § 15. Resolving &lt;color&gt; Values, thus preserving inheritance into child elements.
 </li>
 </ul>
 
@@ -6447,7 +6453,7 @@ <h2 title="Serialization">11. 直列化</h2>
 `相対~色~関数$
 ］の結果【を成す `color^t 】の直列化を追加する。
 ◎
-This section extends CSS Color 4 § 15. Serializing &lt;color&gt; Values to add serialization of the results of the color-mix(), device-cmyk(), and relative color functions.
+This section extends CSS Color 4 § 16. Serializing &lt;color&gt; Values to add serialization of the results of the color-mix(), device-cmyk(), and relative color functions.
 </p>
 
 <p>
@@ -6880,7 +6886,7 @@ <h3 title="Serializing color-mix()">11.1. `color-mix^f の直列化-法</h3>
 — 利用される形は、
 引数~内の `in^v に伴って指定された色~空間に依存する：
 ◎
-Otherwise, it is a &lt;color&gt;, as defined in CSS Color 4 § 15. Serializing &lt;color&gt; Values.＼
+Otherwise, it is a &lt;color&gt;, as defined in CSS Color 4 § 16. Serializing &lt;color&gt; Values.＼
 The form used depends on the color space specified with "in".
 </p>
 
@@ -6944,14 +6950,33 @@ <h3 title="Serializing color-mix()">11.1. `color-mix^f の直列化-法</h3>
 • Because xyz is just an alias for xyz-d65
 </p>
 	</li>
+	<li>
+しかしながら，［
+`hsl$v ／ `hwb$v
+］`色~空間$内で混合した結果に`欠落~成分$
+（`~level 4$ の `§ 欠落~成分との補間-法$
+により`先へ運ばれ$た欠落な~alphaも含む）
+が在る場合、
+元の色~関数と各 `none$v 値を保全するよう，
+`~level 4$ の `§ ~sRGB値の~CSS直列化＠~CSSCOLOR#css-serialization-of-srgb$
+に従って［
+`hsl(h s l / a)^v ／ `hwb(h w b / a)^v
+］の形をとる`現代の色~構文$が利用される
+— `color(srgb r g b)^v の形へ降格することなく
+（そうすると［
+`hsl^v ／ `hwb^v
+］か否かの識別情報が失われる）。
+◎
+However, if the result of mixing in the hsl or hwb color space has at least one missing color component (including a missing alpha carried forward per CSS Color 4 § 13.2 Interpolating with Missing Components), the form used is the modern hsl(h s l / a) or hwb(h w b / a) syntax respectively, preserving the original color function and each none value per CSS Color 4 § 16.2.2 CSS serialization of sRGB values, rather than degrading to color(srgb r g b) (which would lose the hsl/hwb identity).
+</li>
 </ul>
 
 <p>
 往復するための`最小^emな精度は、［
 `~level 4$ の `§ ~color_t 値の直列化-法$
 ］にて指定されたそれと同じとする。
 ◎
-The minimum precision for round-tripping is the same as that specified in CSS Color 4 § 15. Serializing &lt;color&gt; Values.
+The minimum precision for round-tripping is the same as that specified in CSS Color 4 § 16. Serializing &lt;color&gt; Values.
 </p>
 
 <div class="example" id="ex-serial-computed-color-mix">
@@ -7315,77 +7340,101 @@ <h3 title="Serializing Relative Color Functions">11.3. 相対~色~関数の直
 is the string "oklch(from peru l c h)"
 </div>
 
-
 <div class="example" id="ex-serial-rcs-calc">
 <p>
-例えば，
+例えば，宣言d値
 `rgb(from red calc(r / 2) g calc(30%))^v
-を直列化した結果は：
-</p>
-<ul>
-	<li>
-宣言d値である場合
-⇒
-`rgb(from red calc(0.5 * r) g calc(30%))^l,
-</li>
-	<li>
-算出d値である場合
+を直列化した結果は
 ⇒
-`color(srgb 0.5 0 0.3)^l
-</li>
-</ul>
+`rgb(from red calc(0.5 * r) g calc(30%))^l
 ◎
 For example, the serialization of the declared value of
 • rgb(from red calc(r / 2) g calc(30%));
-is the string "rgb(from red calc(0.5 * r) g calc(30%))", while the serialization of the computed value is the string "color(srgb 0.5 0 0.3)".
+is the string "rgb(from red calc(0.5 * r) g calc(30%))",＼
+</p>
+
+<p>
+一方で，その算出d値を直列化した結果は
+⇒
+`color(srgb 0.5 0 0.3)^l
+◎
+while the serialization of the computed value is the string "color(srgb 0.5 0 0.3)".
+</p>
 </div>
 
 <div class="example" id="ex-serial-rcs-nested-none">
 <p>
-例えば，
+例えば，宣言d値
 `hsl(from hsl(none 10% 50%) h s l)^v
-を直列化した結果は：
-</p>
-<ul>
-	<li>
-宣言d値である場合
+を直列化した結果は
 ⇒
-`hsl(from hsl(none 10% 50%) h s l)^l,
-</li>
-	<li>
-算出d値である場合
+`hsl(from hsl(none 10% 50%) h s l)^l
+◎
+For example, the serialization of the declared value of
+• hsl(from hsl(none 10% 50%) h s l);
+is the string "hsl(from hsl(none 10% 50%) h s l)",＼
+</p>
+
+<p>
+一方で，その算出d値を直列化した結果は
 ⇒
 `color(srgb 0.55 0.45 0.45)^l
-</li>
-</ul>
+◎
+while the serialization of the computed value is the string "color(srgb 0.55 0.45 0.45)".
+</p>
+</div>
+
+<div class="example" id="ex-serial-rcs-alpha-none">
+<p>
+例えば，宣言d値
+`hsl(from rebeccapurple none none none / none)^v
+を直列化した結果は
+⇒
+`hsl(from rebeccapurple none none none / none)^l
 ◎
 For example, the serialization of the declared value of
-• hsl(from hsl(none 10% 50%) h s l);
-is the string "hsl(from hsl(none 10% 50%) h s l)", while the serialization of the computed value is the string "color(srgb 0.55 0.45 0.45)".
+◎
+hsl(from rebeccapurple none none none / none);
+◎
+is the string "hsl(from rebeccapurple none none none / none)".
+</p>
+
+<p>
+`算出d値$は，`先へ運ばれ$た欠落な~alphaがあるので
+（~alphaに`相似的な成分$は~alphaである）、
+その［
+色相, 彩度, 明度, ~alpha
+］すべてが`欠落~成分$である`相対~色$ `hsl$f を与える。
+`解決d値$は`欠落~成分$を包含するので、
+その直列化は `hsl$f 用の`現代の色~構文$を利用する
+— 結果は、
+`color(srgb 0 0 0 / none)^l ではなく，
+`hsl(none none none / none)^l になる。
+◎
+The computed value carries forward the missing alpha (alpha is its own analogous component), giving an hsl() relative color whose hue, saturation, lightness, and alpha are all missing. Because the resolved value contains missing color components, the serialization uses the modern hsl() form, yielding the string "hsl(none none none / none)" rather than color(srgb 0 0 0 / none).
+</p>
 </div>
 
 <div class="example" id="ex-serial-rcs-hsl-unclamped">
 <p>
-例えば，
+例えば，宣言d値
 `hsl(from hsl(127.9 302% 25.33%) h s l)^v
-を直列化した結果は：
-</p>
-<ul>
-	<li>
-宣言d値である場合
+を直列化した結果は
 ⇒
 `hsl(from hsl(127.9 302% 25.33%) h s l)^l
-</li>
-	<li>
-算出d値である場合
-⇒
-`color(srgb -0.511666 1.018266 -0.310225)^l
-</li>
-</ul>
 ◎
 For example, the serialization of the declared value of
 • hsl(from hsl(127.9 302% 25.33%) h s l);
-is the string "hsl(from hsl(127.9 302% 25.33%) h s l)", while the serialization of the computed value is the string "color(srgb -0.511666 1.018266 -0.310225)".
+is the string "hsl(from hsl(127.9 302% 25.33%) h s l)",＼
+</p>
+
+<p>
+一方で，その算出d値を直列化した結果は
+⇒
+`color(srgb -0.511666 1.018266 -0.310225)^l
+◎
+while the serialization of the computed value is the string "color(srgb -0.511666 1.018266 -0.310225)".
+</p>
 </div>
 
 <div class="example" id="ex-serial-rcs-currentcolor">
@@ -7404,25 +7453,20 @@ <h3 title="Serializing Relative Color Functions">11.3. 相対~色~関数の直
 </pre>
 
 <p>
-`background-color^p の値を直列化した結果は：
-◎
-↓</p>
-<ul>
-	<li>
-宣言d値である場合
+`background-color^p の宣言d値を直列化した結果は：
 ⇒
 `rgb(from currentcolor r g calc(b / 2))^l
 ◎
 The serialization of the declared value of background-color is the string "rgb(from currentcolor r g calc(b / 2))"＼
-</li>
-	<li>
-算出d値である場合
+</p>
+
+<p>
+一方で，その算出d値を直列化した結果は
 ⇒
 `color(srgb 0 0 0.5)^l
 ◎
 while the serialization of the computed value is the string "color(srgb 0 0 0.5)"
-</li>
-</ul>
+</p>
 </div>
 
 <p>
@@ -7449,7 +7493,7 @@ <h3 title="Serializing Relative Color Functions">11.3. 相対~色~関数の直
 — 利用される形は、
 `相対~色$の色~空間に依存する：
 ◎
-Otherwise, it is the resolved value, which is a &lt;color&gt;, as defined in CSS Color 4 § 15. Serializing &lt;color&gt; Values.
+Otherwise, it is the resolved value, which is a &lt;color&gt;, as defined in CSS Color 4 § 16. Serializing &lt;color&gt; Values.
 ◎
 The form used depends on the color space of the relative color:
 </p>
@@ -7505,6 +7549,30 @@ <h3 title="Serializing Relative Color Functions">11.3. 相対~色~関数の直
 <td>`oklch(l c h)^v
 </table>
 	</li>
+	<li>
+しかしながら，`相対~色$を成す［
+`hsl$f ／ `hwb$f
+］の`解決d値$に`欠落~成分$
+（`~level 4$ の `§ 欠落~成分との補間-法$
+により`起点~色$から`先へ運ばれ$た欠落な~alphaも含む）
+が在る場合、
+元の色~関数と各 `none$v 値を保全するよう，［
+`hsl(h s l / a)^v ／ `hwb(h w b / a)^v
+］の形をとる`現代の色~構文$が利用される
+— `color(srgb r g b)^v の形へ降格することなく
+（そうすると［
+`hsl$v ／ `hwb$v
+］か否かの識別情報が失われる）。
+これは、
+`§ 起点~色の直列化-法＠#serial-origin-color$
+に並行する
+— それは、
+`起点~色$用には，常に現代の~slash構文を発することに加え，
+`~level 4$ の `§ ~sRGB値の~CSS直列化＠~CSSCOLOR#css-serialization-of-srgb$
+による一般な~sRGB直列化~規則に従う。
+◎
+However, if the resolved value of an hsl() or hwb() relative color has at least one missing color component (including a missing alpha carried forward from the origin color per CSS Color 4 § 13.2 Interpolating with Missing Components), the form used is the modern hsl(h s l / a) or hwb(h w b / a) syntax respectively, preserving the original color function and each none value, rather than degrading to color(srgb r g b) (which would lose the hsl/hwb identity). This parallels § 11.2 Serializing Origin Colors, which always emits the modern slash syntax for origin colors, and follows the general sRGB serialization rules in CSS Color 4 § 16.2.2 CSS serialization of sRGB values.
+</li>
 </ul>
 
 <p>
@@ -7513,7 +7581,7 @@ <h3 title="Serializing Relative Color Functions">11.3. 相対~色~関数の直
 <a href="~CSSCOLOR#serializing-color-function-values">§ `color^f 関数の直列化-法</a>
 ］にて指定されたそれと同じとする。
 ◎
-The minimum precision for round-tripping is the same as that specified in CSS Color 4 § 15.5 Serializing values of the color() function.
+The minimum precision for round-tripping is the same as that specified in CSS Color 4 § 16.5 Serializing values of the color() function.
 </p>
 
 <div class="example" id="ex-serial-rcs-computed">