Changeset 252923 in webkit

Timestamp:

Nov 28, 2019 6:44:32 AM (4 years ago)

Author:

Alan Bujtas

Message:

[LFC][IFC] Re-introduce LineBuilder::isVisuallyNonEmpty function
​https://bugs.webkit.org/show_bug.cgi?id=204658
<rdar://problem/57512248>

Reviewed by Antti Koivisto.

LineBuilder::isVisuallyNonEmpty() used to loop through the runs an check if the runs are visually empty or not.
This time it takes the run as the parameter and decides whether this particular run is visually empty or not.
This patch is in preparation for fixing the line's visually-empty state after trimming the trailing runs.

• layout/inlineformatting/InlineLineBuilder.cpp:

(WebCore::Layout::LineBuilder::append):
(WebCore::Layout::LineBuilder::appendNonBreakableSpace):
(WebCore::Layout::LineBuilder::appendTextContent):
(WebCore::Layout::LineBuilder::appendNonReplacedInlineBox):
(WebCore::Layout::LineBuilder::appendReplacedInlineBox):
(WebCore::Layout::LineBuilder::appendLineBreak):
(WebCore::Layout::LineBuilder::isVisuallyNonEmpty const):

• layout/inlineformatting/InlineLineBuilder.h:

Location:

trunk/Source/WebCore

Files:

• ChangeLog (modified) (1 diff)
• layout/inlineformatting/InlineLineBuilder.cpp (modified) (6 diffs)
• layout/inlineformatting/InlineLineBuilder.h (modified) (1 diff)

trunk/Source/WebCore/ChangeLog

@@ +1 @@
+2019-11-28  Zalan Bujtas  <zalan@apple.com>
+
+        [LFC][IFC] Re-introduce LineBuilder::isVisuallyNonEmpty function
+        https://bugs.webkit.org/show_bug.cgi?id=204658
+        <rdar://problem/57512248>
+
+        Reviewed by Antti Koivisto.
+
+        LineBuilder::isVisuallyNonEmpty() used to loop through the runs an check if the runs are visually empty or not.
+        This time it takes the run as the parameter and decides whether this particular run is visually empty or not.
+        This patch is in preparation for fixing the line's visually-empty state after trimming the trailing runs.
+
+        * layout/inlineformatting/InlineLineBuilder.cpp:
+        (WebCore::Layout::LineBuilder::append):
+        (WebCore::Layout::LineBuilder::appendNonBreakableSpace):
+        (WebCore::Layout::LineBuilder::appendTextContent):
+        (WebCore::Layout::LineBuilder::appendNonReplacedInlineBox):
+        (WebCore::Layout::LineBuilder::appendReplacedInlineBox):
+        (WebCore::Layout::LineBuilder::appendLineBreak):
+        (WebCore::Layout::LineBuilder::isVisuallyNonEmpty const):
+        * layout/inlineformatting/InlineLineBuilder.h:
+
 2019-11-28  Zalan Bujtas  <zalan@apple.com>
 

trunk/Source/WebCore/layout/inlineformatting/InlineLineBuilder.cpp

@@ -456 +456 @@
 {
     if (inlineItem.isText())
-        return appendTextContent(downcast<InlineTextItem>(inlineItem), logicalWidth);
-    if (inlineItem.isForcedLineBreak())
-        return appendLineBreak(inlineItem);
-    if (inlineItem.isContainerStart())
-        return appendInlineContainerStart(inlineItem, logicalWidth);
-    if (inlineItem.isContainerEnd())
-        return appendInlineContainerEnd(inlineItem, logicalWidth);
-    if (inlineItem.layoutBox().replaced())
-        return appendReplacedInlineBox(inlineItem, logicalWidth);
-    appendNonReplacedInlineBox(inlineItem, logicalWidth);
+        appendTextContent(downcast<InlineTextItem>(inlineItem), logicalWidth);
+    else if (inlineItem.isForcedLineBreak())
+        appendLineBreak(inlineItem);
+    else if (inlineItem.isContainerStart())
+        appendInlineContainerStart(inlineItem, logicalWidth);
+    else if (inlineItem.isContainerEnd())
+        appendInlineContainerEnd(inlineItem, logicalWidth);
+    else if (inlineItem.layoutBox().replaced())
+        appendReplacedInlineBox(inlineItem, logicalWidth);
+    else if (inlineItem.isBox())
+        appendNonReplacedInlineBox(inlineItem, logicalWidth);
+    else
+        ASSERT_NOT_REACHED();
+
+    // Check if this freshly appended content makes the line visually non-empty.
+    ASSERT(!m_inlineItemRuns.isEmpty());
+    if (m_lineBox.isConsideredEmpty() && isVisuallyNonEmpty(*m_inlineItemRuns.last()))
+        m_lineBox.setIsConsideredNonEmpty();
 }
 
@@ -472 +480 @@
     m_inlineItemRuns.append(makeUnique<InlineItemRun>(inlineItem, logicalRect));
     m_lineBox.expandHorizontally(logicalRect.width());
-    if (logicalRect.width())
-        m_lineBox.setIsConsideredNonEmpty();
 }
 
@@ -532 +538 @@
     if (collapsesToZeroAdvanceWidth)
         lineRun->setCollapsesToZeroAdvanceWidth();
-    else
-        m_lineBox.setIsConsideredNonEmpty();
 
     if (collapsedRun)
@@ -551 +555 @@
     m_inlineItemRuns.append(makeUnique<InlineItemRun>(inlineItem, Display::Rect { 0, contentLogicalWidth() + horizontalMargin.start, logicalWidth, { } }));
     m_lineBox.expandHorizontally(logicalWidth + horizontalMargin.start + horizontalMargin.end);
-    m_lineBox.setIsConsideredNonEmpty();
     m_trimmableContent.clear();
-    if (!layoutBox.establishesFormattingContext() || !boxGeometry.isEmpty())
-        m_lineBox.setIsConsideredNonEmpty();
 }
 
@@ -562 +563 @@
     // FIXME: Surely replaced boxes behave differently.
     appendNonReplacedInlineBox(inlineItem, logicalWidth);
-    m_lineBox.setIsConsideredNonEmpty();
 }
 
 void LineBuilder::appendLineBreak(const InlineItem& inlineItem)
 {
-    m_lineBox.setIsConsideredNonEmpty();
     m_inlineItemRuns.append(makeUnique<InlineItemRun>(inlineItem, Display::Rect { 0, contentLogicalWidth(), { }, { } }));
 }
@@ -678 +677 @@
 }
 
+bool LineBuilder::isVisuallyNonEmpty(const InlineItemRun& run) const
+{
+    if (run.isText())
+        return !run.isCollapsedToZeroAdvanceWidth();
+
+    // Note that this does not check whether the inline container has content. It simply checks if the container itself is considered non-empty.
+    if (run.isContainerStart() || run.isContainerEnd()) {
+        if (!run.logicalRect().width())
+            return false;
+        // Margin does not make the container visually non-empty. Check if it has border or padding.
+        auto& boxGeometry = formattingContext().geometryForBox(run.layoutBox());
+        if (run.isContainerStart())
+            return boxGeometry.borderLeft() || (boxGeometry.paddingLeft() && boxGeometry.paddingLeft().value());
+        return boxGeometry.borderRight() || (boxGeometry.paddingRight() && boxGeometry.paddingRight().value());
+    }
+
+    if (run.isForcedLineBreak())
+        return true;
+
+    if (run.isBox()) {
+        if (!run.layoutBox().establishesFormattingContext())
+            return true;
+        ASSERT(run.layoutBox().isInlineBlockBox());
+        if (!run.logicalRect().width())
+            return false;
+        if (m_skipAlignment || formattingContext().geometryForBox(run.layoutBox()).height())
+            return true;
+        return false;
+    }
+
+    ASSERT_NOT_REACHED();
+    return false;
+}
+
 void LineBuilder::TrimmableContent::append(InlineItemRun& inlineItemRun)
 {

trunk/Source/WebCore/layout/inlineformatting/InlineLineBuilder.h

@@ -146 +146 @@
     void justifyRuns(RunList&) const;
 
+    bool isVisuallyNonEmpty(const InlineItemRun&) const;
+
     LayoutState& layoutState() const;
     const InlineFormattingContext& formattingContext() const;