Diff
Modified: trunk/Source/WebCore/ChangeLog (275980 => 275981)
--- trunk/Source/WebCore/ChangeLog 2021-04-15 00:11:33 UTC (rev 275980)
+++ trunk/Source/WebCore/ChangeLog 2021-04-15 00:15:02 UTC (rev 275981)
@@ -1,3 +1,54 @@
+2021-04-14 Sam Weinig <wei...@apple.com>
+
+ Use range-for loop in target contrast selection to simplify/improve code readability
+ https://bugs.webkit.org/show_bug.cgi?id=224512
+
+ Reviewed by Darin Adler.
+
+ Address some additional post landing feedback from Darin.
+
+ - Use range-for loop in target contrast selection.
+ - Use double to represent luminance, lightness and contrast everywhere.
+ This avoid unnecessary conversions to and from float.
+ - Rename Color::contrastRatio(Color, Color) to just contrastRatio(Color, Color)
+ and move it ColorLuminance.h/cpp with the other contrastRatio overloads.
+
+ * Sources.txt:
+ * WebCore.xcodeproj/project.pbxproj:
+ Add ColorLuminance.cpp
+
+ * css/parser/CSSPropertyParserHelpers.cpp:
+ (WebCore::CSSPropertyParserHelpers::selectFirstColorThatMeetsOrExceedsTargetContrast):
+ Convert colorsToCompareAgainst to an r-value since vector is never used after
+ calling this.
+
+ (WebCore::CSSPropertyParserHelpers::selectFirstColorWithHighestContrast):
+ Convert colorsToCompareAgainst to an r-value since vector is never used after
+ calling this. Also, switch to a range-for loop to aid readability.
+
+ (WebCore::CSSPropertyParserHelpers::parseColorContrastFunctionParameters):
+ Move colorsToCompareAgainst to the select functions.
+
+ * platform/graphics/Color.h:
+ * platform/graphics/Color.cpp:
+ (WebCore::Color::lightness const):
+ (WebCore::Color::luminance const):
+ Use double to represent lightness and luminance.
+
+ (WebCore::Color::contrastRatio): Deleted.
+ Moved to ColorLuminance.h/cpp
+
+ * platform/graphics/ColorLuminance.cpp: Added.
+ (WebCore::contrastRatio):
+ * platform/graphics/ColorLuminance.h:
+ (WebCore::relativeLuminance):
+ (WebCore::contrastRatio):
+ * rendering/RenderTheme.cpp:
+ (WebCore::RenderTheme::disabledTextColor const):
+ * rendering/TextPaintStyle.cpp:
+ (WebCore::textColorIsLegibleAgainstBackgroundColor):
+ Use double to represent luminance and constrast everywhere.
+
2021-04-14 Antti Koivisto <an...@apple.com>
RunIterator::traverseNext/PreviousOnLineIgnoringLineBreak should skip over WBRs
Modified: trunk/Source/WebCore/Sources.txt (275980 => 275981)
--- trunk/Source/WebCore/Sources.txt 2021-04-15 00:11:33 UTC (rev 275980)
+++ trunk/Source/WebCore/Sources.txt 2021-04-15 00:15:02 UTC (rev 275981)
@@ -1935,6 +1935,7 @@
platform/graphics/Color.cpp
platform/graphics/ColorBlending.cpp
platform/graphics/ColorConversion.cpp
+platform/graphics/ColorLuminance.cpp
platform/graphics/ColorSerialization.cpp
platform/graphics/ColorSpace.cpp
platform/graphics/ColorUtilities.cpp
Modified: trunk/Source/WebCore/WebCore.xcodeproj/project.pbxproj (275980 => 275981)
--- trunk/Source/WebCore/WebCore.xcodeproj/project.pbxproj 2021-04-15 00:11:33 UTC (rev 275980)
+++ trunk/Source/WebCore/WebCore.xcodeproj/project.pbxproj 2021-04-15 00:15:02 UTC (rev 275981)
@@ -14227,6 +14227,7 @@
BC6D44EA0C07F2ED0072D2C9 /* JSHTMLEmbedElement.cpp */ = {isa = PBXFileReference; fileEncoding = 30; lastKnownFileType = sourcecode.cpp.cpp; path = JSHTMLEmbedElement.cpp; sourceTree = "<group>"; };
BC6D44EB0C07F2ED0072D2C9 /* JSHTMLEmbedElement.h */ = {isa = PBXFileReference; fileEncoding = 30; lastKnownFileType = sourcecode.c.h; path = JSHTMLEmbedElement.h; sourceTree = "<group>"; };
BC6D6E2509AF943500F59759 /* ScrollView.h */ = {isa = PBXFileReference; fileEncoding = 30; lastKnownFileType = sourcecode.c.h; path = ScrollView.h; sourceTree = "<group>"; };
+ BC6EB84526266B61003225A7 /* ColorLuminance.cpp */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.cpp.cpp; path = ColorLuminance.cpp; sourceTree = "<group>"; };
BC772B360C4EA91E0083285F /* CSSHelper.h */ = {isa = PBXFileReference; fileEncoding = 30; lastKnownFileType = sourcecode.c.h; path = CSSHelper.h; sourceTree = "<group>"; };
BC772C440C4EB2C60083285F /* XMLHttpRequest.cpp */ = {isa = PBXFileReference; fileEncoding = 30; lastKnownFileType = sourcecode.cpp.cpp; path = XMLHttpRequest.cpp; sourceTree = "<group>"; };
BC772C450C4EB2C60083285F /* XMLHttpRequest.h */ = {isa = PBXFileReference; fileEncoding = 30; lastKnownFileType = sourcecode.c.h; path = XMLHttpRequest.h; sourceTree = "<group>"; };
@@ -26798,6 +26799,7 @@
7C514E0224AF80580050710F /* ColorConversion.cpp */,
7C514E0024AF80580050710F /* ColorConversion.h */,
3103B7DE1DB01556008BB890 /* ColorHash.h */,
+ BC6EB84526266B61003225A7 /* ColorLuminance.cpp */,
BC4A23EB25EC160200AAC630 /* ColorLuminance.h */,
7CAC6AE8247F082000E61D59 /* ColorMatrix.h */,
BC10137B25C3624B00DC773C /* ColorModels.h */,
Modified: trunk/Source/WebCore/css/parser/CSSPropertyParserHelpers.cpp (275980 => 275981)
--- trunk/Source/WebCore/css/parser/CSSPropertyParserHelpers.cpp 2021-04-15 00:11:33 UTC (rev 275980)
+++ trunk/Source/WebCore/css/parser/CSSPropertyParserHelpers.cpp 2021-04-15 00:15:02 UTC (rev 275981)
@@ -1509,38 +1509,37 @@
return color;
}
-static Color selectFirstColorThatMeetsOrExceedsTargetContrast(const Color& originBackgroundColor, const Vector<Color>& colorsToCompareAgainst, double targetContrast)
+static Color selectFirstColorThatMeetsOrExceedsTargetContrast(const Color& originBackgroundColor, Vector<Color>&& colorsToCompareAgainst, double targetContrast)
{
auto originBackgroundColorLuminance = originBackgroundColor.luminance();
for (auto& color : colorsToCompareAgainst) {
- auto contrastRatio = WebCore::contrastRatio(originBackgroundColorLuminance, color.luminance());
- if (contrastRatio >= targetContrast)
- return color;
+ if (contrastRatio(originBackgroundColorLuminance, color.luminance()) >= targetContrast)
+ return WTFMove(color);
}
-
+
// If there is a target contrast, and the end of the list is reached without meeting that target,
// either white or black is returned, whichever has the higher contrast.
- auto contrastRatioWithWhite = WebCore::contrastRatio(originBackgroundColorLuminance, 1.0f);
- auto contrastRatioWithBlack = WebCore::contrastRatio(originBackgroundColorLuminance, 0.0f);
- return contrastRatioWithWhite > contrastRatioWithBlack ? Color::white : Color::black;
+ auto contrastWithWhite = contrastRatio(originBackgroundColorLuminance, 1.0);
+ auto contrastWithBlack = contrastRatio(originBackgroundColorLuminance, 0.0);
+ return contrastWithWhite > contrastWithBlack ? Color::white : Color::black;
}
-static Color selectFirstColorWithHighestContrast(const Color& originBackgroundColor, const Vector<Color>& colorsToCompareAgainst)
+static Color selectFirstColorWithHighestContrast(const Color& originBackgroundColor, Vector<Color>&& colorsToCompareAgainst)
{
auto originBackgroundColorLuminance = originBackgroundColor.luminance();
- size_t indexOfColorWithHigestContrastRatio = 0;
- float highestContrastRatioSoFar = 0;
- for (size_t i = 0; i < colorsToCompareAgainst.size(); ++i) {
- auto contrastRatio = WebCore::contrastRatio(originBackgroundColorLuminance, colorsToCompareAgainst[i].luminance());
- if (contrastRatio > highestContrastRatioSoFar) {
- highestContrastRatioSoFar = contrastRatio;
- indexOfColorWithHigestContrastRatio = i;
+ auto* colorWithGreatestContrast = &colorsToCompareAgainst[0];
+ double greatestContrastSoFar = 0;
+ for (auto& color : colorsToCompareAgainst) {
+ auto contrast = contrastRatio(originBackgroundColorLuminance, color.luminance());
+ if (contrast > greatestContrastSoFar) {
+ greatestContrastSoFar = contrast;
+ colorWithGreatestContrast = &color;
}
}
- return colorsToCompareAgainst[indexOfColorWithHigestContrastRatio];
+ return WTFMove(*colorWithGreatestContrast);
}
static Color parseColorContrastFunctionParameters(CSSParserTokenRange& range, const CSSParserContext& context)
@@ -1590,11 +1589,11 @@
return { };
// When a target constast is specified, we select "the first color color to meet or exceed the target contrast."
- return selectFirstColorThatMeetsOrExceedsTargetContrast(originBackgroundColor, colorsToCompareAgainst, *targetContrast);
+ return selectFirstColorThatMeetsOrExceedsTargetContrast(originBackgroundColor, WTFMove(colorsToCompareAgainst), *targetContrast);
}
// When a target constast is NOT specified, we select "the first color with the highest contrast to the single color."
- return selectFirstColorWithHighestContrast(originBackgroundColor, colorsToCompareAgainst);
+ return selectFirstColorWithHighestContrast(originBackgroundColor, WTFMove(colorsToCompareAgainst));
}
enum class ColorMixColorSpace {
Modified: trunk/Source/WebCore/platform/graphics/Color.cpp (275980 => 275981)
--- trunk/Source/WebCore/platform/graphics/Color.cpp 2021-04-15 00:11:33 UTC (rev 275980)
+++ trunk/Source/WebCore/platform/graphics/Color.cpp 2021-04-15 00:15:02 UTC (rev 275981)
@@ -109,15 +109,15 @@
return convertColor<SRGBA<uint8_t>>(SRGBA<float> { multiplier * r, multiplier * g, multiplier * b, a });
}
-float Color::lightness() const
+double Color::lightness() const
{
// FIXME: Replace remaining uses with luminance.
auto [r, g, b, a] = toSRGBALossy<float>();
auto [min, max] = std::minmax({ r, g, b });
- return 0.5f * (max + min);
+ return 0.5 * (max + min);
}
-float Color::luminance() const
+double Color::luminance() const
{
return callOnUnderlyingType([&] (const auto& underlyingColor) {
return WebCore::relativeLuminance(underlyingColor);
@@ -124,15 +124,6 @@
});
}
-float Color::contrastRatio(const Color& colorA, const Color& colorB)
-{
- return colorA.callOnUnderlyingType([&] (const auto& underlyingColorA) {
- return colorB.callOnUnderlyingType([&] (const auto& underlyingColorB) {
- return WebCore::contrastRatio(underlyingColorA, underlyingColorB);
- });
- });
-}
-
Color Color::colorWithAlpha(float alpha) const
{
return callOnUnderlyingType([&] (const auto& underlyingColor) -> Color {
Modified: trunk/Source/WebCore/platform/graphics/Color.h (275980 => 275981)
--- trunk/Source/WebCore/platform/graphics/Color.h 2021-04-15 00:11:33 UTC (rev 275980)
+++ trunk/Source/WebCore/platform/graphics/Color.h 2021-04-15 00:15:02 UTC (rev 275981)
@@ -106,9 +106,8 @@
uint8_t alphaByte() const { return isOutOfLine() ? convertFloatAlphaTo<uint8_t>(asOutOfLine().alpha()) : asInline().alpha; }
float alphaAsFloat() const { return isOutOfLine() ? asOutOfLine().alpha() : convertByteAlphaTo<float>(asInline().alpha); }
- WEBCORE_EXPORT float luminance() const;
- WEBCORE_EXPORT float lightness() const; // FIXME: Replace remaining uses with luminance.
- WEBCORE_EXPORT static float contrastRatio(const Color&, const Color&);
+ WEBCORE_EXPORT double luminance() const;
+ WEBCORE_EXPORT double lightness() const; // FIXME: Replace remaining uses with luminance.
template<typename Functor> decltype(auto) callOnUnderlyingType(Functor&&) const;
Added: trunk/Source/WebCore/platform/graphics/ColorLuminance.cpp (0 => 275981)
--- trunk/Source/WebCore/platform/graphics/ColorLuminance.cpp (rev 0)
+++ trunk/Source/WebCore/platform/graphics/ColorLuminance.cpp 2021-04-15 00:15:02 UTC (rev 275981)
@@ -0,0 +1,42 @@
+/*
+ * Copyright (C) 2021 Apple Inc. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS''
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
+ * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS
+ * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
+ * THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include "config.h"
+#include "ColorLuminance.h"
+
+#include "Color.h"
+
+namespace WebCore {
+
+double contrastRatio(const Color& colorA, const Color& colorB)
+{
+ return colorA.callOnUnderlyingType([&] (const auto& underlyingColorA) {
+ return colorB.callOnUnderlyingType([&] (const auto& underlyingColorB) {
+ return contrastRatio(underlyingColorA, underlyingColorB);
+ });
+ });
+}
+
+}
Modified: trunk/Source/WebCore/platform/graphics/ColorLuminance.h (275980 => 275981)
--- trunk/Source/WebCore/platform/graphics/ColorLuminance.h 2021-04-15 00:11:33 UTC (rev 275980)
+++ trunk/Source/WebCore/platform/graphics/ColorLuminance.h 2021-04-15 00:15:02 UTC (rev 275981)
@@ -29,7 +29,9 @@
namespace WebCore {
-template<typename ColorType> inline float relativeLuminance(const ColorType& color)
+class Color;
+
+template<typename ColorType> inline double relativeLuminance(const ColorType& color)
{
// https://en.wikipedia.org/wiki/Relative_luminance
@@ -46,7 +48,7 @@
return convertColor<XYZA<float, WhitePoint::D65>>(color).y;
}
-inline float contrastRatio(float relativeLuminanceA, float relativeLuminanceB)
+inline double contrastRatio(double relativeLuminanceA, double relativeLuminanceB)
{
// Uses the WCAG 2.0 definition of contrast ratio.
// https://www.w3.org/TR/WCAG20/#contrast-ratiodef
@@ -59,9 +61,11 @@
return (lighterLuminance + 0.05) / (darkerLuminance + 0.05);
}
-template<typename ColorTypeA, typename ColorTypeB> inline float contrastRatio(const ColorTypeA& colorA, const ColorTypeB& colorB)
+template<typename ColorTypeA, typename ColorTypeB> inline double contrastRatio(const ColorTypeA& colorA, const ColorTypeB& colorB)
{
return contrastRatio(relativeLuminance(colorA), relativeLuminance(colorB));
}
+double contrastRatio(const Color&, const Color&);
+
}
Modified: trunk/Source/WebCore/rendering/RenderTheme.cpp (275980 => 275981)
--- trunk/Source/WebCore/rendering/RenderTheme.cpp 2021-04-15 00:11:33 UTC (rev 275980)
+++ trunk/Source/WebCore/rendering/RenderTheme.cpp 2021-04-15 00:15:02 UTC (rev 275981)
@@ -23,6 +23,7 @@
#include "CSSValueKeywords.h"
#include "ColorBlending.h"
+#include "ColorLuminance.h"
#include "ControlStates.h"
#include "Document.h"
#include "FileList.h"
@@ -1409,7 +1410,7 @@
#endif
// Value chosen by observation. This can be tweaked.
-constexpr float minColorContrastValue = 1.195f;
+constexpr double minColorContrastValue = 1.195;
// For transparent or translucent background color, use lightening.
constexpr float minDisabledColorAlphaValue = 0.5f;
@@ -1427,7 +1428,7 @@
// If there's not very much contrast between the disabled color and the background color,
// just leave the text color alone. We don't want to change a good contrast color scheme so that it has really bad contrast.
// If the contrast was already poor, then it doesn't do any good to change it to a different poor contrast color scheme.
- if (Color::contrastRatio(disabledColor, backgroundColor) < minColorContrastValue)
+ if (contrastRatio(disabledColor, backgroundColor) < minColorContrastValue)
return textColor;
return disabledColor;
Modified: trunk/Source/WebCore/rendering/TextPaintStyle.cpp (275980 => 275981)
--- trunk/Source/WebCore/rendering/TextPaintStyle.cpp 2021-04-15 00:11:33 UTC (rev 275980)
+++ trunk/Source/WebCore/rendering/TextPaintStyle.cpp 2021-04-15 00:15:02 UTC (rev 275981)
@@ -26,7 +26,7 @@
#include "config.h"
#include "TextPaintStyle.h"
-#include "ColorUtilities.h"
+#include "ColorLuminance.h"
#include "FocusController.h"
#include "Frame.h"
#include "GraphicsContext.h"
@@ -63,7 +63,7 @@
{
// Uses the WCAG 2.0 definition of legibility: a contrast ratio of 4.5:1 or greater.
// https://www.w3.org/TR/WCAG20/#visual-audio-contrast-contrast
- return Color::contrastRatio(textColor, backgroundColor) > 4.5;
+ return contrastRatio(textColor, backgroundColor) >= 4.5;
}
static Color adjustColorForVisibilityOnBackground(const Color& textColor, const Color& backgroundColor)
