Merge branch 'master' of github.com:w3c/csswg-drafts

Author: una

css-color-4/Overview.bs

@@ -18,6 +18,8 @@ Ignored Terms: stacking context, double, octet
 
 <pre class="link-defaults">
 spec:css-color-4; type:descriptor; for:@color-profile; text:src
+spec:css-color-4; type:dfn; text:colorspace
+spec:css-color-4; type:dfn; text:gamut
 </pre>
 
 <style>
@@ -45,7 +47,9 @@ Introduction</h2>
 
 	<em>This section is not normative.</em>
 
-	This module describes CSS properties which allow authors to specify the foreground color and opacity of the text content of an element.
+	This module describes CSS properties which
+	allow authors to specify
+	the foreground color and opacity of the text content of an element.
 	This module also describes in detail the CSS <<color>> value type.
 
 
@@ -55,6 +59,66 @@ Introduction</h2>
 	and <a href="https://www.w3.org/TR/css-color-3/">CSS Color 3</a>,
 	but also defines new properties and values.
 
+	In particular, it allows specifying colors
+	in other [=colorspaces=] than sRGB;
+	previously, the more saturated colors ouside the sRGB gamut
+	could not be used in CSS
+	even if the display device supported them.
+	In addition to the family of
+	<abbr title="red-green-blue">RGB</abbr> colorspaces,
+	[=colorspaces=] with other primaries
+	such as <abbr title="cyan-magenta-yellow-black">CMYK</abbr> or
+	<abbr title="cyan-magenta-yellow-green-orange-violet-black">CMYGOVK</abbr>
+	are supported.
+
+<h2 id="terminology">Color terminology</h2>
+
+	A <dfn>color</dfn> is a definition (numeric or textual)
+	of the human visual perception of a light
+	or a physical object illuminated with light.
+	The objective study of human color perception is termed
+	<abbr title="colorimetry is the measurement of human color perception">colorimetry</abbr>.
+	If two objects have different
+	<abbr title="the amount of light at each wavelength">spectra</abbr>,
+	but produce the same physical sensation,
+	we say they have the same color.
+
+	<div class="example">For example a green leaf, a photograph of that leaf
+		displayed on a computer screen, and a print of that photograph,
+		are all producing a green sensation by different means.
+		If the screen and the printer are [=calibrated=],
+		the green in the leaf, and the photo, and the print will look the same.
+	</div>
+
+	A <dfn>colorspace</dfn> is an organization of colors
+	with respect to an underlying
+	<abbr title="colorimetry is the measurement of human color perception">colorimetric</abbr>
+	model,
+	such that there is a clear, objectively-measurable meaning
+	for any color in that colorspace.
+	This also means that the same color can be expressed in multiple colorspaces,
+	or transformed from one colorspace to another,
+	while looking the same.
+
+	<div class="example"></div>
+
+	When the measured physical characteristics
+	(such as the chromaticities of the primary colors it uses,
+	or the colors produced in response to a given set of inputs)
+	of a [=colorspace=] or a color-producing device are known,
+	it is said to be <dfn>characterised</dfn>.
+	This characterization information is stored in a <em>profile</em>.
+	The most common type of color profile is defined by the International Color Consortium (ICC) [[!ICC]].
+
+	If in addition adjustments have been made so that a device meets calibration targets
+	such as white point, neutrality of greys, predictability and consistency of tone response,
+	then it is said to be <dfn>calibrated</dfn>.
+
+	Real physical devices cannot yet produce every possible color that the human eye can see.
+	The range of colors that a given device can produce is termed the <dfn>gamut</dfn>
+	<em>not to be confused with gamma</em>.
+	Devices with a limited gamut cannot produce very saturated colors,
+	like those found in a rainbow.
 
 <h2 id="the-color-property">
 Foreground Color: the 'color' property</h2>
@@ -1907,29 +1971,21 @@ Converting gray colors to sRGB  colors</h3>
 <h2 id='icc-colors'>
 Profiled, Device-dependent Colors</h2>
 
-	When the measured physical characteristics
-	(such as the chromaticities of the primary colors it uses,
-	or the colors produced in response to a given set of inputs)
-	of a color space or a color-producing device are known,
-	it is said to be <em>characterised</em>.
-	This characterization information is stored in a <em>profile</em>.
-	The most common type of color profile is defined by the International Color Consortium (ICC) [[!ICC]].
-
-	If in addition adjustments have been made so that a device meets calibration targets
-	such as white point, neutrality of greys, predictability and consistency of tone response,
-	then it is said to be <em>calibrated</em>.
-
-	CSS allows colors to be specified by reference to a color profile.
+	CSS allows [=colors=] to be specified by reference to a color profile.
 	This could be for example a calibrated CMYK printer,
-	or an RGB colorspace (such as ProPhoto <!-- ref -->, <!-- would be good to mention AdobeRGB 1998 here too, need to check trademark and copyright status first --> widely used by photographers), or any other color or monochrome output device which has been characterized.
+	or an RGB colorspace,
+	or any other color or monochrome output device which has been characterized.
+
 	In addition, for convenience,
-	CSS provides several <!-- more than 2 now, update text!! --> -->predefined RGB color spaces:
-	display-p3 [[!DCI-P3]],
+	CSS provides several predefined RGB color spaces
+	including ''display-p3''' [[!DCI-P3]],
 	which is a wide gamut space typical of current wide-gamut monitors,
-	and Rec. 2020 [[!Rec.2020]],
-	which is a ultra-wide gamut space capable of representing almost all visible real-world colors.
-	Both are broadcast industry standards.
+	''prophoto-rgb''', widely used by photographers
+	and ''rec-2020''' [[!Rec.2020]],
+	which is a broadcast industry standard,
+	ultra-wide gamut space capable of representing almost all visible real-world colors.
 
+	These can be used without supplying a separate profile.
 
 	<div class='example'>
 		This example specifies four profiled colors:

css-color-5/Overview.bs

@@ -15,22 +15,27 @@ Abstract: This module extends CSS Color [[css-color-4]] to add color modificatio
 Repository: w3c/csswg-drafts
 </pre>
 
+<pre class="link-defaults">
+spec:css-color-4; type:dfn; text:colorspace
+spec:css-color-4; type:dfn; text:gamut
+</pre>
+
 Introduction {#intro}
 =====================
 
 	<em>This section is not normative.</em>
 
 	Web developers, design tools and design system developers
-	often use color functions to assist in scaling the design 
+	often use color functions to assist in scaling the design
 	of their component color relations.
-	With the increasing usage of design systems that support multiple platforms 
+	With the increasing usage of design systems that support multiple platforms
 	and multiple user preferences, like the increased capability of Dark Mode in UI,
 	this becomes even more useful to not need to manually set color,
 	and to instead have a single source from which schemes are calculated.
 
 	Currently Sass, calc() on HSL values, or PostCSS is used to do this.
-	Preprocessors are unable to work on dynamically adjusted colors, 
-	all current solutions are restricted to the sRGB gamut 
+	Preprocessors are unable to work on dynamically adjusted colors,
+	all current solutions are restricted to the sRGB gamut
 	and to the perceptual limitations of HSL
 	(colors are bunched up in the color wheel,
 	and two colors with visually different lightness,
@@ -57,7 +62,7 @@ Mixing colors: the ''color-mix'' function {#colormix}
 
 	This function takes two <<color>> specifications
 	and returns the result of mixing them,
-	in a given colorspace,
+	in a given [=colorspace=],
 	by a specified amount.
 
 	Unless otherwise specified,

css-ui-4/Overview.bs

@@ -263,7 +263,7 @@ Applies to: all elements
 Inherited: no
 Percentages: N/A
 Computed value: The computed value for ''outline-color/invert'' is ''outline-color/invert''.
- For <<color>> values, see <a>resolving color values</a> in [[!CSS-COLOR-4]].
+ For <<color>> values, see [[!CSS-COLOR-4#resolving-color-values]] in [[!CSS-COLOR-4]].
 Animation type: by computed value
 </pre>
 
@@ -932,7 +932,7 @@ Applies to: all elements
 Inherited: yes
 Percentages: N/A
 Computed value: The computed value for ''caret-color/auto'' is ''caret-color/auto''.
- For <<color>> values, see <a>resolving color values</a> in [[!CSS-COLOR-4]].
+ For <<color>> values, see [[!CSS-COLOR-4#resolving-color-values]] in [[!CSS-COLOR-4]].
 Animation Type: by computed value
 </pre>
 
@@ -1745,7 +1745,7 @@ without adverse consequences to compatibility,
 so this specification allows flexibility.
 
 
-<h2 id="styling-widgets" oldids="form-styling control-styling">Styling Widgets</h2>
+<h2 id="styling-widgets" oldids="form-styling, control-styling">Styling Widgets</h2>
 
 <h3 id="appearance-switching" caniuse="css-appearance">Switching appearance</h3>
 
@@ -2136,17 +2136,24 @@ This appendix is <em>informative</em>.
 <h3 id=changes-22-12-2017 class=no-num>Changes from the
 <a href="https://www.w3.org/TR/2017/WD-css-ui-4-20171222/">22 December 2017 Working Draft</a></h3>
 
+In addition to a number of editorial adjustments,
+the following normative changes have been made:
+
 <ul>
 	<li>Added details about form control specific rendering rules
 	<li>Clarify interaction between text-overflow and annonymous block containers
 	<li>Require the ''cursor/pointer'' cursor for hyperlinks in all document formats
 	<li>Moved the 'box-sizing' and 'text-overflow' properties to [[CSS-SIZING-3]] and [[CSS-OVERFLOW-4]] respectively.
 	<li>Changed the requirement that the ''cursor/text'' cursor matches the writing mode from MAY to MUST
+	<li>The definition of the appearance property has been significantly reworked to make the design compatible with existing web content
 </ul>
 
 <h3 id=changes-22-09-2015 class=no-num>Changes from the
 <a href="https://www.w3.org/TR/2015/WD-css-ui-4-20150922/">22 Sep 2015 First Public Working Draft</a></h3>
 
+In addition to a number of editorial adjustments,
+the following normative changes have been made:
+
 <ul>
 	<li>
 		The caret-animation property have been removed.