- Revision
- 130437
- Author
- [email protected]
- Date
- 2012-10-04 17:35:56 -0700 (Thu, 04 Oct 2012)
Log Message
1ex should equal .5em when the font has no x-height metric
https://bugs.webkit.org/show_bug.cgi?id=80360
Patch by Tab Atkins <[email protected]> on 2012-10-04
Reviewed by Eric Seidel.
Source/WebCore:
Updated FontMetrics and CSSPrimitiveValue to have/use an explicit "hasXHeight" flag to determine how to size an 'ex' unit.
Updated a few of the platform font files to set the flag properly.
Patch cleanup by David Barr <[email protected]>.
Test: fast/css/ex-unit-with-no-x-height.html
* css/CSSPrimitiveValue.cpp:
(WebCore::CSSPrimitiveValue::computeLengthDouble):
* platform/graphics/FontMetrics.h:
(WebCore::FontMetrics::FontMetrics):
(WebCore::FontMetrics::setXHeight):
(FontMetrics):
(WebCore::FontMetrics::hasXHeight):
(WebCore::FontMetrics::setHasXHeight):
(WebCore::FontMetrics::reset):
* platform/graphics/skia/SimpleFontDataSkia.cpp:
(WebCore::SimpleFontData::platformInit):
LayoutTests:
If a font has no x-height metric, 1ex should equal .5em.
Test layout tweaked by David Barr <[email protected]>.
* fast/css/ex-unit-with-no-x-height-expected.txt: Added.
* fast/css/ex-unit-with-no-x-height.html: Added.
Modified Paths
Added Paths
Diff
Modified: trunk/LayoutTests/ChangeLog (130436 => 130437)
--- trunk/LayoutTests/ChangeLog 2012-10-05 00:34:19 UTC (rev 130436)
+++ trunk/LayoutTests/ChangeLog 2012-10-05 00:35:56 UTC (rev 130437)
@@ -1,3 +1,17 @@
+2012-10-04 Tab Atkins <[email protected]>
+
+ 1ex should equal .5em when the font has no x-height metric
+ https://bugs.webkit.org/show_bug.cgi?id=80360
+
+ Reviewed by Eric Seidel.
+
+ If a font has no x-height metric, 1ex should equal .5em.
+
+ Test layout tweaked by David Barr <[email protected]>.
+
+ * fast/css/ex-unit-with-no-x-height-expected.txt: Added.
+ * fast/css/ex-unit-with-no-x-height.html: Added.
+
2012-10-04 Tullio Lucena <[email protected]>
[Qt] New test introduced in r129346 inspector-protocol/css-getSupportedCSSProperties.html fails
Added: trunk/LayoutTests/fast/css/ex-unit-with-no-x-height-expected.txt (0 => 130437)
--- trunk/LayoutTests/fast/css/ex-unit-with-no-x-height-expected.txt (rev 0)
+++ trunk/LayoutTests/fast/css/ex-unit-with-no-x-height-expected.txt 2012-10-05 00:35:56 UTC (rev 130437)
@@ -0,0 +1,10 @@
+This test ensures that the CSS 'ex' unit is treated as half the size of the CSS 'em' unit when a font has no x-height information.
+
+On success, you will see a series of "PASS" messages, followed by "TEST COMPLETE".
+
+
+PASS measureExBox(); is '50px'
+PASS successfullyParsed is true
+
+TEST COMPLETE
+
Added: trunk/LayoutTests/fast/css/ex-unit-with-no-x-height.html (0 => 130437)
--- trunk/LayoutTests/fast/css/ex-unit-with-no-x-height.html (rev 0)
+++ trunk/LayoutTests/fast/css/ex-unit-with-no-x-height.html 2012-10-05 00:35:56 UTC (rev 130437)
@@ -0,0 +1,38 @@
+<!doctype html>
+<svg xmlns = 'http://www.w3.org/2000/svg' style='display:none'>
+ <defs>
+ <font id="Font1">
+ <font-face font-family="block" />
+ </font>
+ </defs>
+</svg>
+
+<style>
+.em { height: .5em; width: .5em; }
+.ex { height: 1ex; width: 1ex; }
+.cover { background: green; }
+.back { background: red; }
+.one { left: 10px; }
+.two { left: 70px; }
+#test > div { font-family: block; font-size: 100px; position: absolute; top: 10px; }
+#description { margin-top: 70px; }
+</style>
+
+<div id='test'>
+ <div class='back em one'></div>
+ <div class='cover ex one' id='ex'></div>
+
+ <div class='back ex two'></div>
+ <div class='cover em two'></div>
+</div>
+<script src=""
+<script>
+description("This test ensures that the CSS 'ex' unit is treated as half the size of the CSS 'em' unit when a font has no x-height information.")
+
+function measureExBox() {
+ return getComputedStyle(document.getElementById('ex')).width;
+}
+
+shouldBe("measureExBox();", "'50px'")
+</script>
+<script src=""
Modified: trunk/Source/WebCore/ChangeLog (130436 => 130437)
--- trunk/Source/WebCore/ChangeLog 2012-10-05 00:34:19 UTC (rev 130436)
+++ trunk/Source/WebCore/ChangeLog 2012-10-05 00:35:56 UTC (rev 130437)
@@ -1,3 +1,30 @@
+2012-10-04 Tab Atkins <[email protected]>
+
+ 1ex should equal .5em when the font has no x-height metric
+ https://bugs.webkit.org/show_bug.cgi?id=80360
+
+ Reviewed by Eric Seidel.
+
+ Updated FontMetrics and CSSPrimitiveValue to have/use an explicit "hasXHeight" flag to determine how to size an 'ex' unit.
+
+ Updated a few of the platform font files to set the flag properly.
+
+ Patch cleanup by David Barr <[email protected]>.
+
+ Test: fast/css/ex-unit-with-no-x-height.html
+
+ * css/CSSPrimitiveValue.cpp:
+ (WebCore::CSSPrimitiveValue::computeLengthDouble):
+ * platform/graphics/FontMetrics.h:
+ (WebCore::FontMetrics::FontMetrics):
+ (WebCore::FontMetrics::setXHeight):
+ (FontMetrics):
+ (WebCore::FontMetrics::hasXHeight):
+ (WebCore::FontMetrics::setHasXHeight):
+ (WebCore::FontMetrics::reset):
+ * platform/graphics/skia/SimpleFontDataSkia.cpp:
+ (WebCore::SimpleFontData::platformInit):
+
2012-10-04 Ryosuke Niwa <[email protected]>
Build fix after r130411. Add the right offset.
Modified: trunk/Source/WebCore/css/CSSPrimitiveValue.cpp (130436 => 130437)
--- trunk/Source/WebCore/css/CSSPrimitiveValue.cpp 2012-10-05 00:34:19 UTC (rev 130436)
+++ trunk/Source/WebCore/css/CSSPrimitiveValue.cpp 2012-10-05 00:35:56 UTC (rev 130437)
@@ -522,7 +522,10 @@
// FIXME: We have a bug right now where the zoom will be applied twice to EX units.
// We really need to compute EX using fontMetrics for the original specifiedSize and not use
// our actual constructed rendering font.
- factor = style->fontMetrics().xHeight();
+ if (style->fontMetrics().hasXHeight())
+ factor = style->fontMetrics().xHeight();
+ else
+ factor = (computingFontSize ? style->fontDescription().specifiedSize() : style->fontDescription().computedSize()) / 2.0;
break;
case CSS_REMS:
if (rootStyle)
Modified: trunk/Source/WebCore/platform/graphics/FontMetrics.h (130436 => 130437)
--- trunk/Source/WebCore/platform/graphics/FontMetrics.h 2012-10-05 00:34:19 UTC (rev 130436)
+++ trunk/Source/WebCore/platform/graphics/FontMetrics.h 2012-10-05 00:35:56 UTC (rev 130437)
@@ -36,6 +36,7 @@
, m_lineGap(0)
, m_lineSpacing(0)
, m_xHeight(0)
+ , m_hasXHeight(false)
{
}
@@ -72,8 +73,15 @@
void setLineSpacing(float lineSpacing) { m_lineSpacing = lineSpacing; }
float xHeight() const { return m_xHeight; }
- void setXHeight(float xHeight) { m_xHeight = xHeight; }
+ void setXHeight(float xHeight)
+ {
+ m_xHeight = xHeight;
+ m_hasXHeight = true;
+ }
+ bool hasXHeight() const { return m_hasXHeight && m_xHeight > 0; }
+ void setHasXHeight(bool hasXHeight) { m_hasXHeight = hasXHeight; }
+
// Integer variants of certain metrics, used for HTML rendering.
int ascent(FontBaseline baselineType = AlphabeticBaseline) const
{
@@ -113,6 +121,7 @@
m_lineGap = 0;
m_lineSpacing = 0;
m_xHeight = 0;
+ m_hasXHeight = false;
}
unsigned m_unitsPerEm;
@@ -121,6 +130,7 @@
float m_lineGap;
float m_lineSpacing;
float m_xHeight;
+ bool m_hasXHeight;
};
static inline float scaleEmToUnits(float x, unsigned unitsPerEm)
Modified: trunk/Source/WebCore/platform/graphics/skia/SimpleFontDataSkia.cpp (130436 => 130437)
--- trunk/Source/WebCore/platform/graphics/skia/SimpleFontDataSkia.cpp 2012-10-05 00:34:19 UTC (rev 130436)
+++ trunk/Source/WebCore/platform/graphics/skia/SimpleFontDataSkia.cpp 2012-10-05 00:35:56 UTC (rev 130437)
@@ -112,16 +112,18 @@
m_fontMetrics.setDescent(descent);
float xHeight;
- if (metrics.fXHeight)
+ if (metrics.fXHeight) {
xHeight = metrics.fXHeight;
- else {
- // hack taken from the Windows port
- xHeight = ascent * 0.56f;
+ m_fontMetrics.setXHeight(xHeight);
+ } else {
+ xHeight = ascent * 0.56; // Best guess from Windows font metrics.
+ m_fontMetrics.setXHeight(xHeight);
+ m_fontMetrics.setHasXHeight(false);
}
+
float lineGap = SkScalarToFloat(metrics.fLeading);
m_fontMetrics.setLineGap(lineGap);
- m_fontMetrics.setXHeight(xHeight);
m_fontMetrics.setLineSpacing(lroundf(ascent) + lroundf(descent) + lroundf(lineGap));
if (platformData().orientation() == Vertical && !isTextOrientationFallback()) {
