Changeset 168624 in webkit

Timestamp:

May 12, 2014 10:56:17 AM (10 years ago)

Author:

Antti Koivisto

Message:

REGRESSION (r159560): Text clips on tile border if line-height < font-size
​https://bugs.webkit.org/show_bug.cgi?id=132822

Reviewed by Andreas Kling.

Source/WebCore:

The first line of simple line layout run range was miscomputed.

Test: fast/text/simple-lines-range-low-line-height.html

• rendering/SimpleLineLayoutResolver.h:

(WebCore::SimpleLineLayout::RunResolver::lineIndexForHeight):

Lines may overlap if line-height < font-size. Apply different adjustment when searching for range begin
so that overflowing earlier lines are taken into account.

(WebCore::SimpleLineLayout::RunResolver::rangeForRect):

LayoutTests:

• fast/text/simple-lines-range-low-line-height-expected.html: Added.
• fast/text/simple-lines-range-low-line-height.html: Added.

Location:

trunk

Files:

• LayoutTests/ChangeLog (modified) (1 diff)
• LayoutTests/fast/text/simple-lines-range-low-line-height-expected.html (added)
• LayoutTests/fast/text/simple-lines-range-low-line-height.html (added)
• Source/WebCore/ChangeLog (modified) (1 diff)
• Source/WebCore/rendering/SimpleLineLayoutResolver.h (modified) (3 diffs)

trunk/LayoutTests/ChangeLog

@@ +1 @@
+2014-05-12  Antti Koivisto  <antti@apple.com>
+
+        REGRESSION (r159560): Text clips on tile border if line-height < font-size
+        https://bugs.webkit.org/show_bug.cgi?id=132822
+
+        Reviewed by Andreas Kling.
+
+        * fast/text/simple-lines-range-low-line-height-expected.html: Added.
+        * fast/text/simple-lines-range-low-line-height.html: Added.
+
 2014-05-12  Krzysztof Wolanski  <k.wolanski@samsung.com>
 

trunk/Source/WebCore/ChangeLog

@@ +1 @@
+2014-05-12  Antti Koivisto  <antti@apple.com>
+
+        REGRESSION (r159560): Text clips on tile border if line-height < font-size
+        https://bugs.webkit.org/show_bug.cgi?id=132822
+
+        Reviewed by Andreas Kling.
+        
+        The first line of simple line layout run range was miscomputed.
+
+        Test: fast/text/simple-lines-range-low-line-height.html
+
+        * rendering/SimpleLineLayoutResolver.h:
+        (WebCore::SimpleLineLayout::RunResolver::lineIndexForHeight):
+        
+            Lines may overlap if line-height < font-size. Apply different adjustment when searching for range begin
+            so that overflowing earlier lines are taken into account.
+
+        (WebCore::SimpleLineLayout::RunResolver::rangeForRect):
+
 2014-05-12  Radu Stavila  <stavila@adobe.com>
 

trunk/Source/WebCore/rendering/SimpleLineLayoutResolver.h

@@ -103 +103 @@
 
 private:
-    unsigned lineIndexForHeight(LayoutUnit) const;
+    enum class IndexType { First, Last };
+    unsigned lineIndexForHeight(LayoutUnit, IndexType) const;
 
     const Layout& m_layout;
@@ -271 +272 @@
 }
 
-inline unsigned RunResolver::lineIndexForHeight(LayoutUnit height) const
+inline unsigned RunResolver::lineIndexForHeight(LayoutUnit height, IndexType type) const
 {
     ASSERT(m_lineHeight);
-    float y = std::max<float>(height - m_borderAndPaddingBefore - m_baseline + m_ascent, 0);
+    float y = height - m_borderAndPaddingBefore;
+    // Lines may overlap, adjust to get the first or last line at this height.
+    if (type == IndexType::First)
+        y += m_lineHeight - (m_baseline + m_descent);
+    else
+        y -= m_baseline - m_ascent;
+    y = std::max<float>(y, 0);
     return std::min<unsigned>(y / m_lineHeight, m_layout.lineCount() - 1);
 }
@@ -283 +290 @@
         return Range<Iterator>(begin(), end());
 
-    unsigned firstLine = lineIndexForHeight(rect.y());
-    unsigned lastLine = std::max(firstLine, lineIndexForHeight(rect.maxY()));
+    unsigned firstLine = lineIndexForHeight(rect.y(), IndexType::First);
+    unsigned lastLine = std::max(firstLine, lineIndexForHeight(rect.maxY(), IndexType::Last));
 
     auto rangeBegin = begin().advanceLines(firstLine);