Changeset 159105 in webkit

Timestamp:

Nov 12, 2013, 6:44:37 AM (11 years ago)

Author:

Antti Koivisto

Message:

Text on simple lines sometimes paints one pixel off
​https://bugs.webkit.org/show_bug.cgi?id=124200

Reviewed by Andreas Kling.

Source/WebCore:

Test: fast/text/line-runs-simple-lines.html

• rendering/SimpleLineLayout.cpp:

(WebCore::SimpleLineLayout::adjustRunOffsets):

Don't round on run construction time.

(WebCore::SimpleLineLayout::createTextRuns):

• rendering/SimpleLineLayoutResolver.h:

(WebCore::SimpleLineLayout::RunResolver::Run::rect):

Instead round when generating rects.

(WebCore::SimpleLineLayout::RunResolver::Run::baseline):

Provide the baseline (used by painting) as unrounded FloatPoint.

LayoutTests:

• fast/text/line-runs-rounding-simple-lines-expected.html: Added.
• fast/text/line-runs-rounding-simple-lines.html: Added.

Location:

trunk

Files:

• LayoutTests/ChangeLog (modified) (1 diff)
• LayoutTests/fast/text/line-runs-rounding-simple-lines-expected.html (added)
• LayoutTests/fast/text/line-runs-rounding-simple-lines.html (added)
• Source/WebCore/ChangeLog (modified) (1 diff)
• Source/WebCore/rendering/SimpleLineLayout.cpp (modified) (2 diffs)
• Source/WebCore/rendering/SimpleLineLayoutResolver.h (modified) (3 diffs)

trunk/LayoutTests/ChangeLog

@@ +1 @@
+2013-11-12  Antti Koivisto  <antti@apple.com>
+
+        Text on simple lines sometimes paints one pixel off
+        https://bugs.webkit.org/show_bug.cgi?id=124200
+
+        Reviewed by Andreas Kling.
+
+        * fast/text/line-runs-rounding-simple-lines-expected.html: Added.
+        * fast/text/line-runs-rounding-simple-lines.html: Added.
+
 2013-11-12  Zan Dobersek  <zdobersek@igalia.com>
 

trunk/Source/WebCore/ChangeLog

@@ +1 @@
+2013-11-12  Antti Koivisto  <antti@apple.com>
+
+        Text on simple lines sometimes paints one pixel off
+        https://bugs.webkit.org/show_bug.cgi?id=124200
+
+        Reviewed by Andreas Kling.
+
+        Test: fast/text/line-runs-simple-lines.html
+
+        * rendering/SimpleLineLayout.cpp:
+        (WebCore::SimpleLineLayout::adjustRunOffsets):
+        
+            Don't round on run construction time.
+
+        (WebCore::SimpleLineLayout::createTextRuns):
+        * rendering/SimpleLineLayoutResolver.h:
+        (WebCore::SimpleLineLayout::RunResolver::Run::rect):
+        
+            Instead round when generating rects.
+
+        (WebCore::SimpleLineLayout::RunResolver::Run::baseline):
+        
+            Provide the baseline (used by painting) as unrounded FloatPoint.
+
 2013-11-11  Andreas Kling  <akling@apple.com>
 

trunk/Source/WebCore/rendering/SimpleLineLayout.cpp

@@ -261 +261 @@
 }
 
-static void adjustRunOffsets(Vector<Run, 4>& lineRuns, ETextAlign textAlign, float lineWidth, float availableWidth)
-{
-    float lineLeft = computeLineLeft(textAlign, availableWidth - lineWidth);
+static void adjustRunOffsets(Vector<Run, 4>& lineRuns, float adjustment)
+{
+    if (!adjustment)
+        return;
     for (unsigned i = 0; i < lineRuns.size(); ++i) {
-        lineRuns[i].left = floor(lineLeft + lineRuns[i].left);
-        lineRuns[i].right = ceil(lineLeft + lineRuns[i].right);
+        lineRuns[i].left += adjustment;
+        lineRuns[i].right += adjustment;
     }
 }
@@ -382 +383 @@
         lineRuns.last().isEndOfLine = true;
 
-        adjustRunOffsets(lineRuns, textAlign, lineWidth.committedWidth(), lineWidth.availableWidth());
+        float lineLeft = computeLineLeft(textAlign, lineWidth.availableWidth() - lineWidth.committedWidth());
+        adjustRunOffsets(lineRuns, lineLeft);
 
         for (unsigned i = 0; i < lineRuns.size(); ++i)

trunk/Source/WebCore/rendering/SimpleLineLayoutResolver.h

@@ -46 +46 @@
 
         LayoutRect rect() const;
-        LayoutPoint baseline() const;
+        FloatPoint baseline() const;
         String text() const;
 
@@ -131 +131 @@
     auto& run = m_iterator.simpleRun();
 
-    LayoutPoint linePosition(run.left, resolver.m_lineHeight * m_iterator.lineIndex() + resolver.m_baseline - resolver.m_ascent);
-    LayoutSize lineSize(run.right - run.left, resolver.m_ascent + resolver.m_descent);
+    LayoutPoint linePosition(floor(run.left), resolver.m_lineHeight * m_iterator.lineIndex() + resolver.m_baseline - resolver.m_ascent);
+    LayoutSize lineSize(ceil(run.right) - floor(run.left), resolver.m_ascent + resolver.m_descent);
     return LayoutRect(linePosition + resolver.m_contentOffset, lineSize);
 }
 
-inline LayoutPoint RunResolver::Run::baseline() const
+inline FloatPoint RunResolver::Run::baseline() const
 {
     auto& resolver = m_iterator.resolver();
@@ -142 +142 @@
 
     float baselineY = resolver.m_lineHeight * m_iterator.lineIndex() + resolver.m_baseline;
-    return LayoutPoint(run.left, baselineY) + resolver.m_contentOffset;
+    return FloatPoint(run.left, baselineY) + resolver.m_contentOffset;
 }