Clean up handling of autosizing state changes.

Source/core/rendering/FastTextAutosizer.cpp

 /*
  * Copyright (C) 2013 Google 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:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 216 matching lines @@
 {
     ASSERT(isPotentialClusterRoot(block));
     return isIndependentDescendant(block) || mightBeWiderOrNarrowerDescendant(block) || block->isTable();
 }
 
 FastTextAutosizer::FastTextAutosizer(const Document* document)
     : m_document(document)
     , m_frameWidth(0)
     , m_layoutWidth(0)
     , m_baseMultiplier(0)
-    , m_pageAutosizingStatus(PageAutosizingStatusUnknown)
+    , m_pageNeedsAutosizing(false)
+    , m_previouslyAutosized(false)
+    , m_updatePageInfoDeferred(false)
     , m_firstBlock(0)
 #ifndef NDEBUG
-    , m_renderViewInfoPrepared(false)
     , m_blocksThatHaveBegunLayout()
 #endif
     , m_superclusters()
     , m_clusterStack()
     , m_fingerprintMapper()
 {
 }
 
 void FastTextAutosizer::record(const RenderBlock* block)
 {
@@ skipping 32 matching lines @@
 #ifndef NDEBUG
         m_blocksThatHaveBegunLayout.add(block);
 #endif
         if (Cluster* cluster = maybeCreateCluster(block))
             m_clusterStack.append(adoptPtr(cluster));
     }
 }
 
 void FastTextAutosizer::beginLayout(RenderBlock* block)
 {
-    ASSERT(enabled() && m_pageAutosizingStatus == PageNeedsAutosizing);
+    ASSERT(enabled() && m_pageNeedsAutosizing);
 #ifndef NDEBUG
     m_blocksThatHaveBegunLayout.add(block);
 #endif
 
     if (!m_firstBlock)  {
         m_firstBlock = block;
         prepareClusterStack(block->parent());
     } else if (block == currentCluster()->m_root) {
         // Ignore beginLayout on the same block twice.
         // This can happen with paginated overflow.
         return;
     }
 
     if (Cluster* cluster = maybeCreateCluster(block)) {
         m_clusterStack.append(adoptPtr(cluster));
         if (block->isTable())
             inflateTable(toRenderTable(block));
     }
 
     if (block->childrenInline() && block->firstChild())
         inflate(block);
 }
 
 void FastTextAutosizer::inflateListItem(RenderListItem* listItem, RenderListMarker* listItemMarker)
 {
-    if (!enabled() || m_pageAutosizingStatus != PageNeedsAutosizing)
+    if (!enabled() || !m_pageNeedsAutosizing)
         return;
     ASSERT(listItem && listItemMarker);
 #ifndef NDEBUG
     m_blocksThatHaveBegunLayout.add(listItem);
 #endif
     // Force the LI to be inside the DBCAT when computing the multiplier.
     // This guarantees that the DBCAT has entered layout, so we can ask for its width.
     // It also makes sense because the list marker is autosized like a text node.
     float multiplier = clusterMultiplier(currentCluster());
 
@@ skipping 42 matching lines @@
                         }
                     }
                 }
             }
         }
     }
 }
 
 void FastTextAutosizer::endLayout(RenderBlock* block)
 {
-    ASSERT(enabled() && m_pageAutosizingStatus == PageNeedsAutosizing);
+    ASSERT(enabled() && m_pageNeedsAutosizing);
 
     if (block == m_firstBlock) {
         m_firstBlock = 0;
-        m_pageAutosizingStatus = PageAutosizingStatusUnknown;
         m_clusterStack.clear();
         m_superclusters.clear();
 #ifndef NDEBUG
         m_blocksThatHaveBegunLayout.clear();
 #endif
     } else if (currentCluster()->m_root == block) {
         m_clusterStack.removeLast();
     }
 }
 
@@ skipping 21 matching lines @@
 }
 
 bool FastTextAutosizer::enabled()
 {
     if (!m_document->settings() || !m_document->page() || m_document->printing())
         return false;
 
     return m_document->settings()->textAutosizingEnabled();
 }
 
-void FastTextAutosizer::updateRenderViewInfo()
+void FastTextAutosizer::updatePageInfoInAllFrames()
 {
+    if (!enabled())
+        return;
+
+    ASSERT(m_document->frame()->isMainFrame());
+
+    for (LocalFrame* frame = m_document->frame(); frame; frame = frame->tree().traverseNext()) {
+        if (FastTextAutosizer* textAutosizer = frame->document()->fastTextAutosizer())
+            textAutosizer->updatePageInfo();
+    }
+}
+
+void FastTextAutosizer::updatePageInfo()
+{
+    if (!enabled() || m_updatePageInfoDeferred)
+        return;
+
+    int previousFrameWidth = m_frameWidth;
+    int previousLayoutWidth = m_layoutWidth;
+    float previousBaseMultiplier = m_baseMultiplier;
+
     RenderView* renderView = toRenderView(m_document->renderer());
     bool horizontalWritingMode = isHorizontalWritingMode(renderView->style()->writingMode());
 
     LocalFrame* mainFrame = m_document->page()->mainFrame();
     IntSize frameSize = m_document->settings()->textAutosizingWindowSizeOverride();
     if (frameSize.isEmpty())
         frameSize = mainFrame->view()->unscaledVisibleContentSize(IncludeScrollbars);
     m_frameWidth = horizontalWritingMode ? frameSize.width() : frameSize.height();
 
     IntSize layoutSize = m_document->page()->mainFrame()->view()->layoutSize();
     m_layoutWidth = horizontalWritingMode ? layoutSize.width() : layoutSize.height();
 
     // Compute the base font scale multiplier based on device and accessibility settings.
     m_baseMultiplier = m_document->settings()->accessibilityFontScaleFactor();
     // If the page has a meta viewport or @viewport, don't apply the device scale adjustment.
     const ViewportDescription& viewportDescription = m_document->page()->mainFrame()->document()->viewportDescription();
     if (!viewportDescription.isSpecifiedByAuthor()) {
         float deviceScaleAdjustment = m_document->settings()->deviceScaleAdjustment();
         m_baseMultiplier *= deviceScaleAdjustment;
     }
 
-    m_pageAutosizingStatus = m_frameWidth && (m_baseMultiplier * (static_cast<float>(m_layoutWidth) / m_frameWidth) > 1.0f)
-        ? PageNeedsAutosizing : PageDoesNotNeedAutosizing;
+    m_pageNeedsAutosizing = !!m_frameWidth
+        && (m_baseMultiplier * (static_cast<float>(m_layoutWidth) / m_frameWidth) > 1.0f);
 
-#ifndef NDEBUG
-    m_renderViewInfoPrepared = true;
-#endif
+    if (!m_pageNeedsAutosizing && m_previouslyAutosized)
+        resetMultipliers();
+
+    if (m_pageNeedsAutosizing
+        && (m_frameWidth != previousFrameWidth
+            || m_layoutWidth != previousLayoutWidth
+            || m_baseMultiplier != previousBaseMultiplier))
+        invalidateMultipliers();
+}
+
+void FastTextAutosizer::resetMultipliers()
+{
+    RenderObject* renderer = m_document->renderer();
+    while (renderer) {
+        if (RenderStyle* style = renderer->style()) {
+            if (style->textAutosizingMultiplier() != 1)
+                applyMultiplier(renderer, 1);

[pdr., 2014/03/24 01:03:18]

Do we need to setNeedsLayout here? Normally, applyMultiplier is called while in
layout where the height changing doesn't matter. When it's called outside of
layout, it can cause the renderobject to need layout because the height can
change.

I suspect applyMultiplier should assert that the renderobject needs layout.

[skobes, 2014/03/25 01:23:24]

You're right, applyMultiplier assumes it is inside layout by using
setStyleInternal instead of setStyle.  I've updated it to take a param to
distinguish this case.

+        }
+        renderer = renderer->nextInPreOrder();
+    }
+    m_previouslyAutosized = false;
+}
+
+void FastTextAutosizer::invalidateMultipliers()

[timvolodine, 2014/03/24 15:24:27]

nit: the name seems a bit confusing, it is not directly clear what the
difference is between invalidateMultipliers and resetMultipliers. maybe
setAllTextNeedsLayout() is a better name?

[skobes, 2014/03/25 01:23:24]

Done.

+{
+    RenderObject* renderer = m_document->renderer();
+    while (renderer) {
+        if (renderer->isText()) {
+            renderer->setNeedsLayout();
+            renderer->parent()->setNeedsLayout();

[pdr., 2014/03/24 01:03:18]

setNeedsLayout already walks up the parent chain so I don't think this parent
one is needed.

[skobes, 2014/03/25 01:23:24]

Done. (This was an unsuccessful initial attempt to fix the line height bug.)

+        }
+        renderer = renderer->nextInPreOrder();
+    }
 }
 
 bool FastTextAutosizer::clusterWouldHaveEnoughTextToAutosize(const RenderBlock* root, const RenderBlock* widthProvider)
 {
     Cluster hypotheticalCluster(root, true, 0);
     return clusterHasEnoughTextToAutosize(&hypotheticalCluster, widthProvider);
 }
 
 bool FastTextAutosizer::clusterHasEnoughTextToAutosize(Cluster* cluster, const RenderBlock* widthProvider)
 {
@@ skipping 152 matching lines @@
             if (ancestors.count(block) == blocks.size())
                 return block;
         }
     }
     ASSERT_NOT_REACHED();
     return 0;
 }
 
 float FastTextAutosizer::clusterMultiplier(Cluster* cluster)
 {
-    ASSERT(m_renderViewInfoPrepared);
     if (!cluster->m_multiplier) {
         if (cluster->m_root->isTable()
             || isIndependentDescendant(cluster->m_root)
             || isWiderOrNarrowerDescendant(cluster)) {
 
             if (cluster->m_supercluster) {
                 cluster->m_multiplier = superclusterMultiplier(cluster);
             } else if (clusterHasEnoughTextToAutosize(cluster)) {
                 cluster->m_multiplier = multiplierFromBlock(clusterWidthProvider(cluster->m_root));
                 // Do not inflate table descendants above the table's multiplier. See inflateTable(...) for details.
@@ skipping 160 matching lines @@
     ASSERT(renderer);
     RenderStyle* currentStyle = renderer->style();
     if (currentStyle->textAutosizingMultiplier() == multiplier)
         return;
 
     // We need to clone the render style to avoid breaking style sharing.
     RefPtr<RenderStyle> style = RenderStyle::clone(currentStyle);
     style->setTextAutosizingMultiplier(multiplier);
     style->setUnique();
     renderer->setStyleInternal(style.release());
+
+    if (multiplier != 1)
+        m_previouslyAutosized = true;
 }
 
 bool FastTextAutosizer::isWiderOrNarrowerDescendant(Cluster* cluster)
 {
     if (!cluster->m_parent || !mightBeWiderOrNarrowerDescendant(cluster->m_root))
         return true;
 
     const RenderBlock* parentDeepestBlockContainingAllText = deepestBlockContainingAllText(cluster->m_parent);
     ASSERT(m_blocksThatHaveBegunLayout.contains(cluster->m_root));
     ASSERT(m_blocksThatHaveBegunLayout.contains(parentDeepestBlockContainingAllText));
@@ skipping 90 matching lines @@
     return *m_blocksForFingerprint.get(fingerprint);
 }
 
 FastTextAutosizer::LayoutScope::LayoutScope(RenderBlock* block)
     : m_textAutosizer(block->document().fastTextAutosizer())
     , m_block(block)
 {
     if (!m_textAutosizer)
         return;
 
-    if (!m_textAutosizer->enabled()) {
-        m_textAutosizer = 0;
-        return;
-    }
-
-    if (m_textAutosizer->m_pageAutosizingStatus == PageAutosizingStatusUnknown)
-        m_textAutosizer->updateRenderViewInfo();
-
-    if (m_textAutosizer->m_pageAutosizingStatus == PageNeedsAutosizing)
+    if (m_textAutosizer->enabled() && m_textAutosizer->m_pageNeedsAutosizing)
         m_textAutosizer->beginLayout(m_block);
     else
         m_textAutosizer = 0;
 }
 
 FastTextAutosizer::LayoutScope::~LayoutScope()
 {
     if (m_textAutosizer)
         m_textAutosizer->endLayout(m_block);
 }
 
 } // namespace WebCore