/*
- * Copyright (C) 2012 Google Inc. All rights reserved.
- * Copyright (C) 2012 Apple Inc. All rights reserved.
+ * Copyright (C) 2013 Google Inc. All rights reserved.
*
- * This library is free software; you can redistribute it and/or
- * modify it under the terms of the GNU Library General Public
- * License as published by the Free Software Foundation; either
- * version 2 of the License, or (at your option) any later version.
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
*
- * This library is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- * Library General Public License for more details.
+ * * 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
+ * copyright notice, this list of conditions and the following disclaimer
+ * in the documentation and/or other materials provided with the
+ * distribution.
+ * * Neither the name of Google Inc. nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
*
- * You should have received a copy of the GNU Library General Public License
- * along with this library; see the file COPYING.LIB. If not, write to
- * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
- * Boston, MA 02110-1301, USA.
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include "config.h"
#include "core/rendering/TextAutosizer.h"
-#include <algorithm>
-
#include "core/dom/Document.h"
-#include "core/html/HTMLDivElement.h"
-#include "core/html/HTMLElement.h"
-#include "core/html/HTMLMetaElement.h"
-#include "core/inspector/InspectorInstrumentation.h"
-#include "core/page/Settings.h"
+#include "core/frame/FrameHost.h"
+#include "core/frame/FrameView.h"
+#include "core/frame/LocalFrame.h"
+#include "core/frame/PinchViewport.h"
+#include "core/frame/Settings.h"
+#include "core/html/HTMLTextAreaElement.h"
+#include "core/page/Page.h"
+#include "core/rendering/InlineIterator.h"
+#include "core/rendering/RenderBlock.h"
#include "core/rendering/RenderListItem.h"
-#include "core/rendering/RenderObject.h"
-#include "core/rendering/RenderText.h"
+#include "core/rendering/RenderListMarker.h"
+#include "core/rendering/RenderTableCell.h"
#include "core/rendering/RenderView.h"
-#include "core/rendering/style/RenderStyle.h"
-#include "core/rendering/style/StyleInheritedData.h"
-#include "platform/TraceEvent.h"
-#include "platform/geometry/IntSize.h"
-#include "wtf/StdLibExtras.h"
-#include "wtf/Vector.h"
-
-namespace WebCore {
-using namespace HTMLNames;
+#ifdef AUTOSIZING_DOM_DEBUG_INFO
+#include "core/dom/ExecutionContextTask.h"
+#endif
-struct TextAutosizingWindowInfo {
- IntSize windowSize;
- IntSize minLayoutSize;
-};
+namespace blink {
-// Represents cluster related data. Instances should not persist between calls to processSubtree.
-struct TextAutosizingClusterInfo {
- explicit TextAutosizingClusterInfo(RenderBlock* root)
- : root(root)
- , blockContainingAllText(0)
- , maxAllowedDifferenceFromTextWidth(150)
+#ifdef AUTOSIZING_DOM_DEBUG_INFO
+class WriteDebugInfoTask : public ExecutionContextTask {
+public:
+ WriteDebugInfoTask(PassRefPtrWillBeRawPtr<Element> element, AtomicString value)
+ : m_element(element)
+ , m_value(value)
{
}
- RenderBlock* root;
- const RenderBlock* blockContainingAllText;
-
- // Upper limit on the difference between the width of the cluster's block containing all
- // text and that of a narrow child before the child becomes a separate cluster.
- float maxAllowedDifferenceFromTextWidth;
+ virtual void performTask(ExecutionContext*)
+ {
+ m_element->setAttribute("data-autosizing", m_value, ASSERT_NO_EXCEPTION);
+ }
- // Descendants of the cluster that are narrower than the block containing all text and must be
- // processed together.
- Vector<TextAutosizingClusterInfo> narrowDescendants;
+private:
+ RefPtrWillBePersistent<Element> m_element;
+ AtomicString m_value;
};
+static void writeDebugInfo(RenderObject* renderer, const AtomicString& output)
+{
+ Node* node = renderer->node();
+ if (!node)
+ return;
+ if (node->isDocumentNode())
+ node = toDocument(node)->documentElement();
+ if (!node->isElementNode())
+ return;
+ node->document().postTask(adoptPtr(new WriteDebugInfoTask(toElement(node), output)));
+}
-static const Vector<QualifiedName>& formInputTags()
+void TextAutosizer::writeClusterDebugInfo(Cluster* cluster)
{
- // Returns the tags for the form input elements.
- DEFINE_STATIC_LOCAL(Vector<QualifiedName>, formInputTags, ());
- if (formInputTags.isEmpty()) {
- formInputTags.append(inputTag);
- formInputTags.append(buttonTag);
- formInputTags.append(selectTag);
+ String explanation = "";
+ if (cluster->m_flags & SUPPRESSING) {
+ explanation = "[suppressed]";
+ } else if (!(cluster->m_flags & (INDEPENDENT | WIDER_OR_NARROWER))) {
+ explanation = "[inherited]";
+ } else if (cluster->m_supercluster) {
+ explanation = "[supercluster]";
+ } else if (!clusterHasEnoughTextToAutosize(cluster)) {
+ explanation = "[insufficient-text]";
+ } else {
+ const RenderBlock* widthProvider = clusterWidthProvider(cluster->m_root);
+ if (cluster->m_hasTableAncestor && cluster->m_multiplier < multiplierFromBlock(widthProvider)) {
+ explanation = "[table-ancestor-limited]";
+ } else {
+ explanation = String::format("[from width %d of %s]",
+ static_cast<int>(widthFromBlock(widthProvider)), widthProvider->debugName().utf8().data());
+ }
}
- return formInputTags;
+ String pageInfo = "";
+ if (cluster->m_root->isRenderView()) {
+ pageInfo = String::format("; pageinfo: bm %f * (lw %d / fw %d)",
+ m_pageInfo.m_baseMultiplier, m_pageInfo.m_layoutWidth, m_pageInfo.m_frameWidth);
+ }
+ float multiplier = cluster->m_flags & SUPPRESSING ? 1.0 : cluster->m_multiplier;
+ writeDebugInfo(const_cast<RenderBlock*>(cluster->m_root),
+ AtomicString(String::format("cluster: %f %s%s", multiplier,
+ explanation.utf8().data(), pageInfo.utf8().data())));
}
+#endif
-static const String& vBulletinForumCommentId()
+static const RenderObject* parentElementRenderer(const RenderObject* renderer)
{
- // Websites using vBulletin forum software typically contain <div id="post_message_*"..> blocks.
- DEFINE_STATIC_LOCAL(const String, vBulletinForumCommentId, ("post_message_"));
- return vBulletinForumCommentId;
+ // At style recalc, the renderer's parent may not be attached,
+ // so we need to obtain this from the DOM tree.
+ const Node* node = renderer->node();
+ if (!node)
+ return 0;
+
+ // FIXME: This should be using NodeRenderingTraversal::parent().
+ if (Element* parent = node->parentElement())
+ return parent->renderer();
+ return 0;
}
-static bool isVBulletinComment(const RenderBlock* block)
+static bool isNonTextAreaFormControl(const RenderObject* renderer)
{
- Node* blockNode = block->node();
- if (blockNode && blockNode->hasTagName(divTag)) {
- const HTMLDivElement* element = toHTMLDivElement(blockNode);
- if (element && element->hasID() && element->idForStyleResolution().startsWith(vBulletinForumCommentId()))
- return true;
- }
- return false;
+ const Node* node = renderer ? renderer->node() : 0;
+ if (!node || !node->isElementNode())
+ return false;
+ const Element* element = toElement(node);
+
+ return (element->isFormControlElement() && !isHTMLTextAreaElement(element));
}
-static bool hasForumCommentAncestor(const RenderBlock* container)
+static bool isPotentialClusterRoot(const RenderObject* renderer)
{
- for (const RenderBlock* block = container; block; block = block->containingBlock()) {
- if (isVBulletinComment(block))
- return true;
- }
- return false;
+ // "Potential cluster roots" are the smallest unit for which we can
+ // enable/disable text autosizing.
+ // - Must not be inline, as different multipliers on one line looks terrible.
+ // Exceptions are inline-block and alike elements (inline-table, -webkit-inline-*),
+ // as they often contain entire multi-line columns of text.
+ // - Must not be normal list items, as items in the same list should look
+ // consistent, unless they are floating or position:absolute/fixed.
+ Node* node = renderer->generatingNode();
+ if (node && !node->hasChildren())
+ return false;
+ if (!renderer->isRenderBlock())
+ return false;
+ if (renderer->isInline() && !renderer->style()->isDisplayReplacedType())
+ return false;
+ if (renderer->isListItem())
+ return (renderer->isFloating() || renderer->isOutOfFlowPositioned());
+
+ return true;
}
-static RenderListItem* getAncestorListItem(const RenderObject* renderer)
+static bool isIndependentDescendant(const RenderBlock* renderer)
{
- RenderObject* ancestor = renderer->parent();
- while (ancestor && (ancestor->isRenderInline() || ancestor->isAnonymousBlock()))
- ancestor = ancestor->parent();
+ ASSERT(isPotentialClusterRoot(renderer));
- return (ancestor && ancestor->isListItem()) ? toRenderListItem(ancestor) : 0;
+ RenderBlock* containingBlock = renderer->containingBlock();
+ return renderer->isRenderView()
+ || renderer->isFloating()
+ || renderer->isOutOfFlowPositioned()
+ || renderer->isTableCell()
+ || renderer->isTableCaption()
+ || renderer->isFlexibleBoxIncludingDeprecated()
+ || renderer->hasColumns()
+ || (containingBlock && containingBlock->isHorizontalWritingMode() != renderer->isHorizontalWritingMode())
+ || renderer->style()->isDisplayReplacedType()
+ || renderer->isTextArea()
+ || renderer->style()->userModify() != READ_ONLY;
}
-static RenderObject* getAncestorList(const RenderObject* renderer)
+static bool blockIsRowOfLinks(const RenderBlock* block)
{
- // FIXME: Add support for <menu> elements as a possible ancestor of an <li> element,
- // see http://www.whatwg.org/specs/web-apps/current-work/multipage/grouping-content.html#the-li-element
- for (RenderObject* ancestor = renderer->parent(); ancestor; ancestor = ancestor->parent()) {
- Node* parentNode = ancestor->generatingNode();
- if (parentNode && (parentNode->hasTagName(olTag) || parentNode->hasTagName(ulTag)))
- return ancestor;
+ // A "row of links" is a block for which:
+ // 1. It does not contain non-link text elements longer than 3 characters
+ // 2. It contains a minimum of 3 inline links and all links should
+ // have the same specified font size.
+ // 3. It should not contain <br> elements.
+ // 4. It should contain only inline elements unless they are containers,
+ // children of link elements or children of sub-containers.
+ int linkCount = 0;
+ RenderObject* renderer = block->firstChild();
+ float matchingFontSize = -1;
+
+ while (renderer) {
+ if (!isPotentialClusterRoot(renderer)) {
+ if (renderer->isText() && toRenderText(renderer)->text().stripWhiteSpace().length() > 3)
+ return false;
+ if (!renderer->isInline() || renderer->isBR())
+ return false;
+ }
+ if (renderer->style()->isLink()) {
+ linkCount++;
+ if (matchingFontSize < 0)
+ matchingFontSize = renderer->style()->specifiedFontSize();
+ else if (matchingFontSize != renderer->style()->specifiedFontSize())
+ return false;
+
+ // Skip traversing descendants of the link.
+ renderer = renderer->nextInPreOrderAfterChildren(block);
+ continue;
+ }
+ renderer = renderer->nextInPreOrder(block);
}
- return 0;
+
+ return (linkCount >= 3);
}
-TextAutosizer::TextAutosizer(Document* document)
- : m_document(document)
- , m_contentType(Unknown)
+static bool blockHeightConstrained(const RenderBlock* block)
{
+ // FIXME: Propagate constrainedness down the tree, to avoid inefficiently walking back up from each box.
+ // FIXME: This code needs to take into account vertical writing modes.
+ // FIXME: Consider additional heuristics, such as ignoring fixed heights if the content is already overflowing before autosizing kicks in.
+ for (; block; block = block->containingBlock()) {
+ RenderStyle* style = block->style();
+ if (style->overflowY() >= OSCROLL)
+ return false;
+ if (style->height().isSpecified() || style->maxHeight().isSpecified() || block->isOutOfFlowPositioned()) {
+ // Some sites (e.g. wikipedia) set their html and/or body elements to height:100%,
+ // without intending to constrain the height of the content within them.
+ return !block->isDocumentElement() && !block->isBody();
+ }
+ if (block->isFloating())
+ return false;
+ }
+ return false;
}
-void TextAutosizer::recalculateMultipliers()
+static bool blockOrImmediateChildrenAreFormControls(const RenderBlock* block)
{
- RenderObject* renderer = m_document->renderer();
+ if (isNonTextAreaFormControl(block))
+ return true;
+ const RenderObject* renderer = block->firstChild();
while (renderer) {
- if (renderer->style() && renderer->style()->textAutosizingMultiplier() != 1)
- setMultiplier(renderer, 1);
- renderer = renderer->nextInPreOrder();
+ if (isNonTextAreaFormControl(renderer))
+ return true;
+ renderer = renderer->nextSibling();
}
+
+ return false;
}
-TextAutosizer::ContentType TextAutosizer::detectContentType()
+// Some blocks are not autosized even if their parent cluster wants them to.
+static bool blockSuppressesAutosizing(const RenderBlock* block)
{
- RefPtr<NodeList> metaElements = m_document->getElementsByTagNameNS(xhtmlNamespaceURI, metaTag.localName());
- for (unsigned i = 0; i < metaElements->length(); ++i) {
- HTMLMetaElement* metaElement = toHTMLMetaElement(metaElements->item(i));
- if (equalIgnoringCase(metaElement->name(), "generator") && metaElement->content().startsWith("vBulletin", false))
- return VBulletin;
- }
- return Default;
+ if (blockOrImmediateChildrenAreFormControls(block))
+ return true;
+
+ if (blockIsRowOfLinks(block))
+ return true;
+
+ // Don't autosize block-level text that can't wrap (as it's likely to
+ // expand sideways and break the page's layout).
+ if (!block->style()->autoWrap())
+ return true;
+
+ if (blockHeightConstrained(block))
+ return true;
+
+ return false;
}
-bool TextAutosizer::processSubtree(RenderObject* layoutRoot)
+static bool hasExplicitWidth(const RenderBlock* block)
{
- TRACE_EVENT0("webkit", "TextAutosizer::processSubtree");
-
- if (!m_document->settings() || !m_document->settings()->textAutosizingEnabled() || layoutRoot->view()->document().printing() || !m_document->page())
- return false;
+ // FIXME: This heuristic may need to be expanded to other ways a block can be wider or narrower
+ // than its parent containing block.
+ return block->style() && block->style()->width().isSpecified();
+}
- InspectorInstrumentation::willAutosizeText(layoutRoot);
- if (m_contentType == Unknown && m_document->body())
- m_contentType = detectContentType();
+TextAutosizer::TextAutosizer(const Document* document)
+ : m_document(document)
+ , m_firstBlockToBeginLayout(0)
+#if ENABLE(ASSERT)
+ , m_blocksThatHaveBegunLayout()
+#endif
+ , m_superclusters()
+ , m_clusterStack()
+ , m_fingerprintMapper()
+ , m_pageInfo()
+ , m_updatePageInfoDeferred(false)
+{
+}
- Frame* mainFrame = m_document->page()->mainFrame();
+void TextAutosizer::record(const RenderBlock* block)
+{
+ if (!m_pageInfo.m_settingEnabled)
+ return;
- TextAutosizingWindowInfo windowInfo;
+ ASSERT(!m_blocksThatHaveBegunLayout.contains(block));
- // Window area, in logical (density-independent) pixels.
- windowInfo.windowSize = m_document->settings()->textAutosizingWindowSizeOverride();
- if (windowInfo.windowSize.isEmpty())
- windowInfo.windowSize = mainFrame->view()->unscaledVisibleContentSize(ScrollableArea::IncludeScrollbars);
+ if (!classifyBlock(block, INDEPENDENT | EXPLICIT_WIDTH))
+ return;
- // Largest area of block that can be visible at once (assuming the main
- // frame doesn't get scaled to less than overview scale), in CSS pixels.
- windowInfo.minLayoutSize = mainFrame->view()->layoutSize();
- for (Frame* frame = m_document->frame(); frame; frame = frame->tree().parent())
- windowInfo.minLayoutSize = windowInfo.minLayoutSize.shrunkTo(frame->view()->layoutSize());
+ if (Fingerprint fingerprint = computeFingerprint(block))
+ m_fingerprintMapper.addTentativeClusterRoot(block, fingerprint);
+}
- // The layoutRoot could be neither a container nor a cluster, so walk up the tree till we find each of these.
- RenderBlock* container = layoutRoot->isRenderBlock() ? toRenderBlock(layoutRoot) : layoutRoot->containingBlock();
- while (container && !isAutosizingContainer(container))
- container = container->containingBlock();
+void TextAutosizer::destroy(const RenderBlock* block)
+{
+ if (!m_pageInfo.m_settingEnabled && !m_fingerprintMapper.hasFingerprints())
+ return;
- RenderBlock* cluster = container;
- while (cluster && (!isAutosizingContainer(cluster) || !isIndependentDescendant(cluster)))
- cluster = cluster->containingBlock();
+ ASSERT(!m_blocksThatHaveBegunLayout.contains(block));
- TextAutosizingClusterInfo clusterInfo(cluster);
- processCluster(clusterInfo, container, layoutRoot, windowInfo);
- InspectorInstrumentation::didAutosizeText(layoutRoot);
- return true;
+ if (m_fingerprintMapper.remove(block) && m_firstBlockToBeginLayout) {
+ // RenderBlock with a fingerprint was destroyed during layout.
+ // Clear the cluster stack and the supercluster map to avoid stale pointers.
+ // Speculative fix for http://crbug.com/369485.
+ m_firstBlockToBeginLayout = 0;
+ m_clusterStack.clear();
+ m_superclusters.clear();
+ }
}
-float TextAutosizer::clusterMultiplier(WritingMode writingMode, const TextAutosizingWindowInfo& windowInfo, float textWidth) const
+TextAutosizer::BeginLayoutBehavior TextAutosizer::prepareForLayout(const RenderBlock* block)
{
- int logicalWindowWidth = isHorizontalWritingMode(writingMode) ? windowInfo.windowSize.width() : windowInfo.windowSize.height();
- int logicalLayoutWidth = isHorizontalWritingMode(writingMode) ? windowInfo.minLayoutSize.width() : windowInfo.minLayoutSize.height();
- // Ignore box width in excess of the layout width, to avoid extreme multipliers.
- float logicalClusterWidth = std::min<float>(textWidth, logicalLayoutWidth);
+#if ENABLE(ASSERT)
+ m_blocksThatHaveBegunLayout.add(block);
+#endif
- float multiplier = logicalClusterWidth / logicalWindowWidth;
- multiplier *= m_document->settings()->textAutosizingFontScaleFactor();
+ if (!m_firstBlockToBeginLayout) {
+ m_firstBlockToBeginLayout = block;
+ prepareClusterStack(block->parent());
+ } else if (block == currentCluster()->m_root) {
+ // Ignore beginLayout on the same block twice.
+ // This can happen with paginated overflow.
+ return StopLayout;
+ }
+
+ return ContinueLayout;
+}
+
+void TextAutosizer::prepareClusterStack(const RenderObject* renderer)
+{
+ if (!renderer)
+ return;
+ prepareClusterStack(renderer->parent());
- // 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()) {
- multiplier *= m_document->settings()->deviceScaleAdjustment();
+ if (renderer->isRenderBlock()) {
+ const RenderBlock* block = toRenderBlock(renderer);
+#if ENABLE(ASSERT)
+ m_blocksThatHaveBegunLayout.add(block);
+#endif
+ if (Cluster* cluster = maybeCreateCluster(block))
+ m_clusterStack.append(adoptPtr(cluster));
}
- return std::max(1.0f, multiplier);
}
-void TextAutosizer::processClusterInternal(TextAutosizingClusterInfo& clusterInfo, RenderBlock* container, RenderObject* subtreeRoot, const TextAutosizingWindowInfo& windowInfo, float multiplier)
+void TextAutosizer::beginLayout(RenderBlock* block)
{
- processContainer(multiplier, container, clusterInfo, subtreeRoot, windowInfo);
+ ASSERT(shouldHandleLayout());
+
+ if (prepareForLayout(block) == StopLayout)
+ return;
- Vector<Vector<TextAutosizingClusterInfo> > narrowDescendantsGroups;
- getNarrowDescendantsGroupedByWidth(clusterInfo, narrowDescendantsGroups);
- for (size_t i = 0; i < narrowDescendantsGroups.size(); ++i)
- processCompositeCluster(narrowDescendantsGroups[i], windowInfo);
+ if (Cluster* cluster = maybeCreateCluster(block))
+ m_clusterStack.append(adoptPtr(cluster));
+
+ // Cells in auto-layout tables are handled separately by inflateAutoTable.
+ bool isAutoTableCell = block->isTableCell() && !toRenderTableCell(block)->table()->style()->isFixedTableLayout();
+ if (!isAutoTableCell && !m_clusterStack.isEmpty())
+ inflate(block);
}
-void TextAutosizer::processCluster(TextAutosizingClusterInfo& clusterInfo, RenderBlock* container, RenderObject* subtreeRoot, const TextAutosizingWindowInfo& windowInfo)
+void TextAutosizer::inflateListItem(RenderListItem* listItem, RenderListMarker* listItemMarker)
{
- // Many pages set a max-width on their content. So especially for the RenderView, instead of
- // just taking the width of |cluster| we find the lowest common ancestor of the first and last
- // descendant text node of the cluster (i.e. the deepest wrapper block that contains all the
- // text), and use its width instead.
- clusterInfo.blockContainingAllText = findDeepestBlockContainingAllText(clusterInfo.root);
- float textWidth = clusterInfo.blockContainingAllText->contentLogicalWidth();
- float multiplier = 1.0;
- if (clusterShouldBeAutosized(clusterInfo, textWidth))
- multiplier = clusterMultiplier(clusterInfo.root->style()->writingMode(), windowInfo, textWidth);
- processClusterInternal(clusterInfo, container, subtreeRoot, windowInfo, multiplier);
+ if (!shouldHandleLayout())
+ return;
+ ASSERT(listItem && listItemMarker);
+
+ if (prepareForLayout(listItem) == StopLayout)
+ return;
+
+ // 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());
+
+ applyMultiplier(listItem, multiplier);
+ applyMultiplier(listItemMarker, multiplier);
}
-void TextAutosizer::processCompositeCluster(Vector<TextAutosizingClusterInfo>& clusterInfos, const TextAutosizingWindowInfo& windowInfo)
+void TextAutosizer::inflateAutoTable(RenderTable* table)
{
- if (clusterInfos.isEmpty())
+ ASSERT(table);
+ ASSERT(!table->style()->isFixedTableLayout());
+ ASSERT(table->containingBlock());
+
+ Cluster* cluster = currentCluster();
+ if (cluster->m_root != table)
return;
- float maxTextWidth = 0;
- for (size_t i = 0; i < clusterInfos.size(); ++i) {
- TextAutosizingClusterInfo& clusterInfo = clusterInfos[i];
- clusterInfo.blockContainingAllText = findDeepestBlockContainingAllText(clusterInfo.root);
- maxTextWidth = max<float>(maxTextWidth, clusterInfo.blockContainingAllText->contentLogicalWidth());
+ // Pre-inflate cells that have enough text so that their inflated preferred widths will be used
+ // for column sizing.
+ for (RenderObject* section = table->firstChild(); section; section = section->nextSibling()) {
+ if (!section->isTableSection())
+ continue;
+ for (RenderTableRow* row = toRenderTableSection(section)->firstRow(); row; row = row->nextRow()) {
+ for (RenderTableCell* cell = row->firstCell(); cell; cell = cell->nextCell()) {
+ if (!cell->needsLayout())
+ continue;
+
+ beginLayout(cell);
+ inflate(cell, DescendToInnerBlocks);
+ endLayout(cell);
+ }
+ }
}
+}
- float multiplier = 1.0;
- if (compositeClusterShouldBeAutosized(clusterInfos, maxTextWidth))
- multiplier = clusterMultiplier(clusterInfos[0].root->style()->writingMode(), windowInfo, maxTextWidth);
- for (size_t i = 0; i < clusterInfos.size(); ++i) {
- ASSERT(clusterInfos[i].root->style()->writingMode() == clusterInfos[0].root->style()->writingMode());
- processClusterInternal(clusterInfos[i], clusterInfos[i].root, clusterInfos[i].root, windowInfo, multiplier);
+void TextAutosizer::endLayout(RenderBlock* block)
+{
+ ASSERT(shouldHandleLayout());
+
+ if (block == m_firstBlockToBeginLayout) {
+ m_firstBlockToBeginLayout = 0;
+ m_clusterStack.clear();
+ m_superclusters.clear();
+ m_stylesRetainedDuringLayout.clear();
+#if ENABLE(ASSERT)
+ m_blocksThatHaveBegunLayout.clear();
+#endif
+ // Tables can create two layout scopes for the same block so the isEmpty
+ // check below is needed to guard against endLayout being called twice.
+ } else if (!m_clusterStack.isEmpty() && currentCluster()->m_root == block) {
+ m_clusterStack.removeLast();
}
}
-void TextAutosizer::processContainer(float multiplier, RenderBlock* container, TextAutosizingClusterInfo& clusterInfo, RenderObject* subtreeRoot, const TextAutosizingWindowInfo& windowInfo)
+float TextAutosizer::inflate(RenderObject* parent, InflateBehavior behavior, float multiplier)
{
- ASSERT(isAutosizingContainer(container));
+ Cluster* cluster = currentCluster();
+ bool hasTextChild = false;
- float localMultiplier = containerShouldBeAutosized(container) ? multiplier: 1;
+ RenderObject* child = 0;
+ if (parent->isRenderBlock() && (parent->childrenInline() || behavior == DescendToInnerBlocks))
+ child = toRenderBlock(parent)->firstChild();
+ else if (parent->isRenderInline())
+ child = toRenderInline(parent)->firstChild();
- RenderObject* descendant = nextInPreOrderSkippingDescendantsOfContainers(subtreeRoot, subtreeRoot);
- while (descendant) {
- if (descendant->isText()) {
- if (localMultiplier != 1 && descendant->style()->textAutosizingMultiplier() == 1) {
- setMultiplier(descendant, localMultiplier);
- setMultiplier(descendant->parent(), localMultiplier); // Parent does line spacing.
-
- if (RenderListItem* listItemAncestor = getAncestorListItem(descendant)) {
- if (RenderObject* list = getAncestorList(listItemAncestor)) {
- if (list->style()->textAutosizingMultiplier() == 1)
- setMultiplierForList(list, localMultiplier);
- }
- }
- }
- } else if (isAutosizingContainer(descendant)) {
- RenderBlock* descendantBlock = toRenderBlock(descendant);
- TextAutosizingClusterInfo descendantClusterInfo(descendantBlock);
- if (isWiderDescendant(descendantBlock, clusterInfo) || isIndependentDescendant(descendantBlock))
- processCluster(descendantClusterInfo, descendantBlock, descendantBlock, windowInfo);
- else if (isNarrowDescendant(descendantBlock, clusterInfo)) {
- // Narrow descendants are processed together later to be able to apply the same multiplier
- // to each of them if necessary.
- clusterInfo.narrowDescendants.append(descendantClusterInfo);
- } else
- processContainer(multiplier, descendantBlock, clusterInfo, descendantBlock, windowInfo);
+ while (child) {
+ if (child->isText()) {
+ hasTextChild = true;
+ // We only calculate this multiplier on-demand to ensure the parent block of this text
+ // has entered layout.
+ if (!multiplier)
+ multiplier = cluster->m_flags & SUPPRESSING ? 1.0f : clusterMultiplier(cluster);
+ applyMultiplier(child, multiplier);
+ // FIXME: Investigate why MarkOnlyThis is sufficient.
+ if (parent->isRenderInline())
+ child->setPreferredLogicalWidthsDirty(MarkOnlyThis);
+ } else if (child->isRenderInline()) {
+ multiplier = inflate(child, behavior, multiplier);
+ } else if (child->isRenderBlock() && behavior == DescendToInnerBlocks
+ && !classifyBlock(child, INDEPENDENT | EXPLICIT_WIDTH | SUPPRESSING)) {
+ multiplier = inflate(child, behavior, multiplier);
}
- descendant = nextInPreOrderSkippingDescendantsOfContainers(descendant, subtreeRoot);
+ child = child->nextSibling();
}
+
+ if (hasTextChild) {
+ applyMultiplier(parent, multiplier); // Parent handles line spacing.
+ } else if (!parent->isListItem()) {
+ // For consistency, a block with no immediate text child should always have a
+ // multiplier of 1 (except for list items which are handled in inflateListItem).
+ applyMultiplier(parent, 1);
+ }
+ return multiplier;
}
-void TextAutosizer::setMultiplier(RenderObject* renderer, float multiplier)
+bool TextAutosizer::shouldHandleLayout() const
{
- // FIXME: Investigate if a clone() is needed and whether it does the right thing w.r.t. style sharing.
- RefPtr<RenderStyle> newStyle = RenderStyle::clone(renderer->style());
- newStyle->setTextAutosizingMultiplier(multiplier);
- renderer->setStyle(newStyle.release());
+ return m_pageInfo.m_settingEnabled && m_pageInfo.m_pageNeedsAutosizing && !m_updatePageInfoDeferred;
}
-void TextAutosizer::setMultiplierForList(RenderObject* renderer, float multiplier)
+void TextAutosizer::updatePageInfoInAllFrames()
{
-#ifndef NDEBUG
- Node* parentNode = renderer->generatingNode();
- ASSERT(parentNode);
- ASSERT(parentNode->hasTagName(olTag) || parentNode->hasTagName(ulTag));
-#endif
- setMultiplier(renderer, multiplier);
+ ASSERT(!m_document->frame() || m_document->frame()->isMainFrame());
- // Make sure all list items are autosized consistently.
- for (RenderObject* child = renderer->firstChild(); child; child = child->nextSibling()) {
- if (child->isListItem() && child->style()->textAutosizingMultiplier() == 1)
- setMultiplier(child, multiplier);
+ for (Frame* frame = m_document->frame(); frame; frame = frame->tree().traverseNext()) {
+ if (!frame->isLocalFrame())
+ continue;
+ if (TextAutosizer* textAutosizer = toLocalFrame(frame)->document()->textAutosizer())
+ textAutosizer->updatePageInfo();
}
}
-float TextAutosizer::computeAutosizedFontSize(float specifiedSize, float multiplier)
+void TextAutosizer::updatePageInfo()
{
- // Somewhat arbitrary "pleasant" font size.
- const float pleasantSize = 16;
+ if (m_updatePageInfoDeferred || !m_document->page() || !m_document->settings())
+ return;
- // Multiply fonts that the page author has specified to be larger than
- // pleasantSize by less and less, until huge fonts are not increased at all.
- // For specifiedSize between 0 and pleasantSize we directly apply the
- // multiplier; hence for specifiedSize == pleasantSize, computedSize will be
- // multiplier * pleasantSize. For greater specifiedSizes we want to
- // gradually fade out the multiplier, so for every 1px increase in
- // specifiedSize beyond pleasantSize we will only increase computedSize
- // by gradientAfterPleasantSize px until we meet the
- // computedSize = specifiedSize line, after which we stay on that line (so
- // then every 1px increase in specifiedSize increases computedSize by 1px).
- const float gradientAfterPleasantSize = 0.5;
+ PageInfo previousPageInfo(m_pageInfo);
+ m_pageInfo.m_settingEnabled = m_document->settings()->textAutosizingEnabled();
- float computedSize;
- if (specifiedSize <= pleasantSize)
- computedSize = multiplier * specifiedSize;
- else {
- computedSize = multiplier * pleasantSize + gradientAfterPleasantSize * (specifiedSize - pleasantSize);
- if (computedSize < specifiedSize)
- computedSize = specifiedSize;
+ if (!m_pageInfo.m_settingEnabled || m_document->printing()) {
+ m_pageInfo.m_pageNeedsAutosizing = false;
+ } else {
+ RenderView* renderView = m_document->renderView();
+ bool horizontalWritingMode = isHorizontalWritingMode(renderView->style()->writingMode());
+
+ // FIXME: With out-of-process iframes, the top frame can be remote and
+ // doesn't have sizing information. Just return if this is the case.
+ Frame* frame = m_document->frame()->tree().top();
+ if (frame->isRemoteFrame())
+ return;
+
+ LocalFrame* mainFrame = m_document->page()->deprecatedLocalMainFrame();
+ IntSize frameSize = m_document->settings()->textAutosizingWindowSizeOverride();
+ if (frameSize.isEmpty())
+ frameSize = windowSize();
+
+ m_pageInfo.m_frameWidth = horizontalWritingMode ? frameSize.width() : frameSize.height();
+
+ IntSize layoutSize = mainFrame->view()->layoutSize();
+ m_pageInfo.m_layoutWidth = horizontalWritingMode ? layoutSize.width() : layoutSize.height();
+
+ // Compute the base font scale multiplier based on device and accessibility settings.
+ m_pageInfo.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 = mainFrame->document()->viewportDescription();
+ if (!viewportDescription.isSpecifiedByAuthor()) {
+ float deviceScaleAdjustment = m_document->settings()->deviceScaleAdjustment();
+ m_pageInfo.m_baseMultiplier *= deviceScaleAdjustment;
+ }
+
+ m_pageInfo.m_pageNeedsAutosizing = !!m_pageInfo.m_frameWidth
+ && (m_pageInfo.m_baseMultiplier * (static_cast<float>(m_pageInfo.m_layoutWidth) / m_pageInfo.m_frameWidth) > 1.0f);
+ }
+
+ if (m_pageInfo.m_pageNeedsAutosizing) {
+ // If page info has changed, multipliers may have changed. Force a layout to recompute them.
+ if (m_pageInfo.m_frameWidth != previousPageInfo.m_frameWidth
+ || m_pageInfo.m_layoutWidth != previousPageInfo.m_layoutWidth
+ || m_pageInfo.m_baseMultiplier != previousPageInfo.m_baseMultiplier
+ || m_pageInfo.m_settingEnabled != previousPageInfo.m_settingEnabled)
+ setAllTextNeedsLayout();
+ } else if (previousPageInfo.m_hasAutosized) {
+ // If we are no longer autosizing the page, we won't do anything during the next layout.
+ // Set all the multipliers back to 1 now.
+ resetMultipliers();
+ m_pageInfo.m_hasAutosized = false;
}
- return computedSize;
}
-bool TextAutosizer::isAutosizingContainer(const RenderObject* renderer)
+IntSize TextAutosizer::windowSize() const
{
- // "Autosizing containers" are the smallest unit for which we can
- // enable/disable Text Autosizing.
- // - Must not be inline, as different multipliers on one line looks terrible.
- // Exceptions are inline-block and alike elements (inline-table, -webkit-inline-*),
- // as they often contain entire multi-line columns of text.
- // - Must not be list items, as items in the same list should look consistent (*).
- // - Must not be normal list items, as items in the same list should look
- // consistent, unless they are floating or position:absolute/fixed.
- if (!renderer->isRenderBlock() || (renderer->isInline() && !renderer->style()->isDisplayReplacedType()))
- return false;
- if (renderer->isListItem())
- return renderer->isFloating() || renderer->isOutOfFlowPositioned();
- // Avoid creating containers for text within text controls, buttons, or <select> buttons.
- Node* parentNode = renderer->parent() ? renderer->parent()->generatingNode() : 0;
- if (parentNode && parentNode->isElementNode() && formInputTags().contains(toElement(parentNode)->tagQName()))
- return false;
+ Page * page = m_document->page();
+ ASSERT(page);
+ return page->settings().pinchVirtualViewportEnabled() ?
+ page->frameHost().pinchViewport().size() :
+ page->deprecatedLocalMainFrame()->view()->unscaledVisibleContentSize(IncludeScrollbars);
+}
- return true;
+void TextAutosizer::resetMultipliers()
+{
+ RenderObject* renderer = m_document->renderView();
+ while (renderer) {
+ if (RenderStyle* style = renderer->style()) {
+ if (style->textAutosizingMultiplier() != 1)
+ applyMultiplier(renderer, 1, LayoutNeeded);
+ }
+ renderer = renderer->nextInPreOrder();
+ }
}
-bool TextAutosizer::isNarrowDescendant(const RenderBlock* renderer, TextAutosizingClusterInfo& parentClusterInfo)
+void TextAutosizer::setAllTextNeedsLayout()
{
- ASSERT(isAutosizingContainer(renderer));
+ RenderObject* renderer = m_document->renderView();
+ while (renderer) {
+ if (renderer->isText())
+ renderer->setNeedsLayoutAndFullPaintInvalidation();
+ renderer = renderer->nextInPreOrder();
+ }
+}
- // Autosizing containers that are significantly narrower than the |blockContainingAllText| of
- // their enclosing cluster may be acting as separate columns, hence must be autosized
- // separately. For example the 2nd div in:
- // <body>
- // <div style="float: right; width: 50%"></div>
- // <div style="width: 50%"></div>
- // <body>
- // is the left column, and should be autosized differently from the body.
- // If however the container is only narrower by 150px or less, it's considered part of
- // the enclosing cluster. This 150px limit is adjusted whenever a descendant container is
- // less than 50px narrower than the current limit.
- const float differenceFromMaxWidthDifference = 50;
- float contentWidth = renderer->contentLogicalWidth();
- float clusterTextWidth = parentClusterInfo.blockContainingAllText->contentLogicalWidth();
- float widthDifference = clusterTextWidth - contentWidth;
+TextAutosizer::BlockFlags TextAutosizer::classifyBlock(const RenderObject* renderer, BlockFlags mask) const
+{
+ if (!renderer->isRenderBlock())
+ return 0;
- if (widthDifference - parentClusterInfo.maxAllowedDifferenceFromTextWidth > differenceFromMaxWidthDifference)
- return true;
+ const RenderBlock* block = toRenderBlock(renderer);
+ BlockFlags flags = 0;
- parentClusterInfo.maxAllowedDifferenceFromTextWidth = std::max(widthDifference, parentClusterInfo.maxAllowedDifferenceFromTextWidth);
- return false;
-}
+ if (isPotentialClusterRoot(block)) {
+ if (mask & POTENTIAL_ROOT)
+ flags |= POTENTIAL_ROOT;
-bool TextAutosizer::isWiderDescendant(const RenderBlock* renderer, const TextAutosizingClusterInfo& parentClusterInfo)
-{
- ASSERT(isAutosizingContainer(renderer));
-
- // Autosizing containers that are wider than the |blockContainingAllText| of their enclosing
- // cluster are treated the same way as autosizing clusters to be autosized separately.
- float contentWidth = renderer->contentLogicalWidth();
- float clusterTextWidth = parentClusterInfo.blockContainingAllText->contentLogicalWidth();
- return contentWidth > clusterTextWidth;
-}
-
-bool TextAutosizer::isIndependentDescendant(const RenderBlock* renderer)
-{
- ASSERT(isAutosizingContainer(renderer));
-
- // "Autosizing clusters" are special autosizing containers within which we
- // want to enforce a uniform text size multiplier, in the hopes of making
- // the major sections of the page look internally consistent.
- // All their descendants (including other autosizing containers) must share
- // the same multiplier, except for subtrees which are themselves clusters,
- // and some of their descendant containers might not be autosized at all
- // (for example if their height is constrained).
- // Additionally, clusterShouldBeAutosized requires each cluster to contain a
- // minimum amount of text, without which it won't be autosized.
- //
- // Clusters are chosen using very similar criteria to CSS flow roots, aka
- // block formatting contexts (http://w3.org/TR/css3-box/#flow-root), since
- // flow roots correspond to box containers that behave somewhat
- // independently from their parent (for example they don't overlap floats).
- // The definition of a flow root also conveniently includes most of the
- // ways that a box and its children can have significantly different width
- // from the box's parent (we want to avoid having significantly different
- // width blocks within a cluster, since the narrower blocks would end up
- // larger than would otherwise be necessary).
- return renderer->isRenderView()
- || renderer->isFloating()
- || renderer->isOutOfFlowPositioned()
- || renderer->isTableCell()
- || renderer->isTableCaption()
- || renderer->isFlexibleBoxIncludingDeprecated()
- || renderer->hasColumns()
- || renderer->containingBlock()->isHorizontalWritingMode() != renderer->isHorizontalWritingMode()
- || renderer->style()->isDisplayReplacedType()
- || renderer->isTextArea()
- || renderer->style()->userModify() != READ_ONLY;
- // FIXME: Tables need special handling to multiply all their columns by
- // the same amount even if they're different widths; so do hasColumns()
- // containers, and probably flexboxes...
+ if ((mask & INDEPENDENT) && (isIndependentDescendant(block) || block->isTable()))
+ flags |= INDEPENDENT;
+
+ if ((mask & EXPLICIT_WIDTH) && hasExplicitWidth(block))
+ flags |= EXPLICIT_WIDTH;
+
+ if ((mask & SUPPRESSING) && blockSuppressesAutosizing(block))
+ flags |= SUPPRESSING;
+ }
+ return flags;
}
-bool TextAutosizer::isAutosizingCluster(const RenderBlock* renderer, TextAutosizingClusterInfo& parentClusterInfo)
+bool TextAutosizer::clusterWouldHaveEnoughTextToAutosize(const RenderBlock* root, const RenderBlock* widthProvider)
{
- ASSERT(isAutosizingContainer(renderer));
-
- return isNarrowDescendant(renderer, parentClusterInfo)
- || isWiderDescendant(renderer, parentClusterInfo)
- || isIndependentDescendant(renderer);
+ Cluster hypotheticalCluster(root, classifyBlock(root), 0);
+ return clusterHasEnoughTextToAutosize(&hypotheticalCluster, widthProvider);
}
-bool TextAutosizer::containerShouldBeAutosized(const RenderBlock* container)
+bool TextAutosizer::clusterHasEnoughTextToAutosize(Cluster* cluster, const RenderBlock* widthProvider)
{
- if (containerContainsOneOfTags(container, formInputTags()))
- return false;
+ if (cluster->m_hasEnoughTextToAutosize != UnknownAmountOfText)
+ return cluster->m_hasEnoughTextToAutosize == HasEnoughText;
- if (containerIsRowOfLinks(container))
- return false;
+ const RenderBlock* root = cluster->m_root;
+ if (!widthProvider)
+ widthProvider = clusterWidthProvider(root);
- // Don't autosize block-level text that can't wrap (as it's likely to
- // expand sideways and break the page's layout).
- if (!container->style()->autoWrap())
+ // TextAreas and user-modifiable areas get a free pass to autosize regardless of text content.
+ if (root->isTextArea() || (root->style() && root->style()->userModify() != READ_ONLY)) {
+ cluster->m_hasEnoughTextToAutosize = HasEnoughText;
+ return true;
+ }
+
+ if (cluster->m_flags & SUPPRESSING) {
+ cluster->m_hasEnoughTextToAutosize = NotEnoughText;
return false;
+ }
- return !contentHeightIsConstrained(container);
-}
+ // 4 lines of text is considered enough to autosize.
+ float minimumTextLengthToAutosize = widthFromBlock(widthProvider) * 4;
-bool TextAutosizer::containerContainsOneOfTags(const RenderBlock* container, const Vector<QualifiedName>& tags)
-{
- const RenderObject* renderer = container;
- while (renderer) {
- const Node* rendererNode = renderer->node();
- if (rendererNode && rendererNode->isElementNode()) {
- if (tags.contains(toElement(rendererNode)->tagQName()))
+ float length = 0;
+ RenderObject* descendant = root->firstChild();
+ while (descendant) {
+ if (descendant->isRenderBlock()) {
+ if (classifyBlock(descendant, INDEPENDENT | SUPPRESSING)) {
+ descendant = descendant->nextInPreOrderAfterChildren(root);
+ continue;
+ }
+ } else if (descendant->isText()) {
+ // Note: Using text().stripWhiteSpace().length() instead of renderedTextLength() because
+ // the lineboxes will not be built until layout. These values can be different.
+ // Note: This is an approximation assuming each character is 1em wide.
+ length += toRenderText(descendant)->text().stripWhiteSpace().length() * descendant->style()->specifiedFontSize();
+
+ if (length >= minimumTextLengthToAutosize) {
+ cluster->m_hasEnoughTextToAutosize = HasEnoughText;
return true;
+ }
}
- renderer = nextInPreOrderSkippingDescendantsOfContainers(renderer, container);
+ descendant = descendant->nextInPreOrder(root);
}
+ cluster->m_hasEnoughTextToAutosize = NotEnoughText;
return false;
}
-bool TextAutosizer::containerIsRowOfLinks(const RenderObject* container)
+TextAutosizer::Fingerprint TextAutosizer::getFingerprint(const RenderObject* renderer)
{
- // A "row of links" is a container for which holds:
- // 1. it should not contain non-link text elements longer than 3 characters
- // 2. it should contain min. 3 inline links and all links should
- // have the same specified font size
- // 3. it should not contain <br> elements
- // 4. it should contain only inline elements unless they are containers,
- // children of link elements or children of sub-containers.
- int linkCount = 0;
- RenderObject* renderer = container->nextInPreOrder(container);
- float matchingFontSize = -1;
+ Fingerprint result = m_fingerprintMapper.get(renderer);
+ if (!result) {
+ result = computeFingerprint(renderer);
+ m_fingerprintMapper.add(renderer, result);
+ }
+ return result;
+}
- while (renderer) {
- if (!isAutosizingContainer(renderer)) {
- if (renderer->isText() && toRenderText(renderer)->text().impl()->stripWhiteSpace()->length() > 3)
- return false;
- if (!renderer->isInline())
- return false;
- if (renderer->isBR())
- return false;
- }
- if (renderer->style()->isLink()) {
- if (matchingFontSize < 0)
- matchingFontSize = renderer->style()->specifiedFontSize();
- else {
- if (matchingFontSize != renderer->style()->specifiedFontSize())
- return false;
- }
+TextAutosizer::Fingerprint TextAutosizer::computeFingerprint(const RenderObject* renderer)
+{
+ Node* node = renderer->generatingNode();
+ if (!node || !node->isElementNode())
+ return 0;
- linkCount++;
- // Skip traversing descendants of the link.
- renderer = renderer->nextInPreOrderAfterChildren(container);
- } else
- renderer = nextInPreOrderSkippingDescendantsOfContainers(renderer, container);
+ FingerprintSourceData data;
+ if (const RenderObject* parent = parentElementRenderer(renderer))
+ data.m_parentHash = getFingerprint(parent);
+
+ data.m_qualifiedNameHash = QualifiedNameHash::hash(toElement(node)->tagQName());
+
+ if (RenderStyle* style = renderer->style()) {
+ data.m_packedStyleProperties = style->direction();
+ data.m_packedStyleProperties |= (style->position() << 1);
+ data.m_packedStyleProperties |= (style->floating() << 4);
+ data.m_packedStyleProperties |= (style->display() << 6);
+ data.m_packedStyleProperties |= (style->width().type() << 11);
+ // packedStyleProperties effectively using 15 bits now.
+
+ // consider for adding: writing mode, padding.
+
+ data.m_width = style->width().getFloatValue();
}
- return (linkCount >= 3);
+ // Use nodeIndex as a rough approximation of column number
+ // (it's too early to call RenderTableCell::col).
+ // FIXME: account for colspan
+ if (renderer->isTableCell())
+ data.m_column = renderer->node()->nodeIndex();
+
+ return StringHasher::computeHash<UChar>(
+ static_cast<const UChar*>(static_cast<const void*>(&data)),
+ sizeof data / sizeof(UChar));
}
-bool TextAutosizer::contentHeightIsConstrained(const RenderBlock* container)
+TextAutosizer::Cluster* TextAutosizer::maybeCreateCluster(const RenderBlock* block)
{
- // FIXME: Propagate constrainedness down the tree, to avoid inefficiently walking back up from each box.
- // FIXME: This code needs to take into account vertical writing modes.
- // FIXME: Consider additional heuristics, such as ignoring fixed heights if the content is already overflowing before autosizing kicks in.
- for (; container; container = container->containingBlock()) {
- RenderStyle* style = container->style();
- if (style->overflowY() >= OSCROLL)
- return false;
- if (style->height().isSpecified() || style->maxHeight().isSpecified() || container->isOutOfFlowPositioned()) {
- // Some sites (e.g. wikipedia) set their html and/or body elements to height:100%,
- // without intending to constrain the height of the content within them.
- return !container->isRoot() && !container->isBody();
- }
- if (container->isFloating())
- return false;
+ BlockFlags flags = classifyBlock(block);
+ if (!(flags & POTENTIAL_ROOT))
+ return 0;
+
+ Cluster* parentCluster = m_clusterStack.isEmpty() ? 0 : currentCluster();
+ ASSERT(parentCluster || block->isRenderView());
+
+ // If a non-independent block would not alter the SUPPRESSING flag, it doesn't need to be a cluster.
+ bool parentSuppresses = parentCluster && (parentCluster->m_flags & SUPPRESSING);
+ if (!(flags & INDEPENDENT) && !(flags & EXPLICIT_WIDTH) && !!(flags & SUPPRESSING) == parentSuppresses)
+ return 0;
+
+ Cluster* cluster = new Cluster(block, flags, parentCluster, getSupercluster(block));
+#ifdef AUTOSIZING_DOM_DEBUG_INFO
+ // Non-SUPPRESSING clusters are annotated in clusterMultiplier.
+ if (flags & SUPPRESSING)
+ writeClusterDebugInfo(cluster);
+#endif
+ return cluster;
+}
+
+TextAutosizer::Supercluster* TextAutosizer::getSupercluster(const RenderBlock* block)
+{
+ Fingerprint fingerprint = m_fingerprintMapper.get(block);
+ if (!fingerprint)
+ return 0;
+
+ BlockSet* roots = m_fingerprintMapper.getTentativeClusterRoots(fingerprint);
+ if (!roots || roots->size() < 2 || !roots->contains(block))
+ return 0;
+
+ SuperclusterMap::AddResult addResult = m_superclusters.add(fingerprint, PassOwnPtr<Supercluster>());
+ if (!addResult.isNewEntry)
+ return addResult.storedValue->value.get();
+
+ Supercluster* supercluster = new Supercluster(roots);
+ addResult.storedValue->value = adoptPtr(supercluster);
+ return supercluster;
+}
+
+float TextAutosizer::clusterMultiplier(Cluster* cluster)
+{
+ if (cluster->m_multiplier)
+ return cluster->m_multiplier;
+
+ // FIXME: why does isWiderOrNarrowerDescendant crash on independent clusters?
+ if (!(cluster->m_flags & INDEPENDENT) && isWiderOrNarrowerDescendant(cluster))
+ cluster->m_flags |= WIDER_OR_NARROWER;
+
+ if (cluster->m_flags & (INDEPENDENT | WIDER_OR_NARROWER)) {
+ if (cluster->m_supercluster)
+ cluster->m_multiplier = superclusterMultiplier(cluster);
+ else if (clusterHasEnoughTextToAutosize(cluster))
+ cluster->m_multiplier = multiplierFromBlock(clusterWidthProvider(cluster->m_root));
+ else
+ cluster->m_multiplier = 1.0f;
+ } else {
+ cluster->m_multiplier = cluster->m_parent ? clusterMultiplier(cluster->m_parent) : 1.0f;
}
- return false;
+
+#ifdef AUTOSIZING_DOM_DEBUG_INFO
+ writeClusterDebugInfo(cluster);
+#endif
+
+ ASSERT(cluster->m_multiplier);
+ return cluster->m_multiplier;
}
-bool TextAutosizer::clusterShouldBeAutosized(TextAutosizingClusterInfo& clusterInfo, float blockWidth)
-{
- Vector<TextAutosizingClusterInfo> clusterInfos(1, clusterInfo);
- return compositeClusterShouldBeAutosized(clusterInfos, blockWidth);
-}
-
-bool TextAutosizer::compositeClusterShouldBeAutosized(Vector<TextAutosizingClusterInfo>& clusterInfos, float blockWidth)
-{
- // Don't autosize clusters that contain less than 4 lines of text (in
- // practice less lines are required, since measureDescendantTextWidth
- // assumes that characters are 1em wide, but most characters are narrower
- // than that, so we're overestimating their contribution to the linecount).
- //
- // This is to reduce the likelihood of autosizing things like headers and
- // footers, which can be quite visually distracting. The rationale is that
- // if a cluster contains very few lines of text then it's ok to have to zoom
- // in and pan from side to side to read each line, since if there are very
- // few lines of text you'll only need to pan across once or twice.
- //
- // An exception to the 4 lines of text are the textarea and contenteditable
- // clusters, which are always autosized by default (i.e. treated as if they
- // contain more than 4 lines of text). This is to ensure that the text does
- // not suddenly get autosized when the user enters more than 4 lines of text.
- // Another exception are the forum comments which are autosized by default
- // to guarantee consistency.
- float totalTextWidth = 0;
- const float minLinesOfText = 4;
- float minTextWidth = blockWidth * minLinesOfText;
- for (size_t i = 0; i < clusterInfos.size(); ++i) {
- if (clusterInfos[i].root->isTextArea() || (clusterInfos[i].root->style() && clusterInfos[i].root->style()->userModify() != READ_ONLY))
+bool TextAutosizer::superclusterHasEnoughTextToAutosize(Supercluster* supercluster, const RenderBlock* widthProvider)
+{
+ if (supercluster->m_hasEnoughTextToAutosize != UnknownAmountOfText)
+ return supercluster->m_hasEnoughTextToAutosize == HasEnoughText;
+
+ BlockSet::iterator end = supercluster->m_roots->end();
+ for (BlockSet::iterator it = supercluster->m_roots->begin(); it != end; ++it) {
+ if (clusterWouldHaveEnoughTextToAutosize(*it, widthProvider)) {
+ supercluster->m_hasEnoughTextToAutosize = HasEnoughText;
return true;
- if (m_contentType == VBulletin) {
- if (hasForumCommentAncestor(clusterInfos[i].blockContainingAllText)
- || clusterContainsForumComment(clusterInfos[i].blockContainingAllText, clusterInfos[i]))
- return true;
}
- measureDescendantTextWidth(clusterInfos[i].blockContainingAllText, clusterInfos[i], minTextWidth, totalTextWidth);
- if (totalTextWidth >= minTextWidth)
- return true;
}
+ supercluster->m_hasEnoughTextToAutosize = NotEnoughText;
return false;
}
-bool TextAutosizer::clusterContainsForumComment(const RenderBlock* container, TextAutosizingClusterInfo& clusterInfo)
+float TextAutosizer::superclusterMultiplier(Cluster* cluster)
{
- ASSERT(m_contentType == VBulletin);
+ Supercluster* supercluster = cluster->m_supercluster;
+ if (!supercluster->m_multiplier) {
+ const RenderBlock* widthProvider = maxClusterWidthProvider(cluster->m_supercluster, cluster->m_root);
+ supercluster->m_multiplier = superclusterHasEnoughTextToAutosize(supercluster, widthProvider)
+ ? multiplierFromBlock(widthProvider) : 1.0f;
+ }
+ ASSERT(supercluster->m_multiplier);
+ return supercluster->m_multiplier;
+}
- RenderObject* descendant = nextInPreOrderSkippingDescendantsOfContainers(container, container);
- while (descendant) {
- if (isAutosizingContainer(descendant)) {
- RenderBlock* descendantBlock = toRenderBlock(descendant);
- if (isVBulletinComment(descendantBlock))
- return true;
- if (!isAutosizingCluster(descendantBlock, clusterInfo)
- && clusterContainsForumComment(descendantBlock, clusterInfo))
- return true;
+const RenderBlock* TextAutosizer::clusterWidthProvider(const RenderBlock* root) const
+{
+ if (root->isTable() || root->isTableCell())
+ return root;
+
+ return deepestBlockContainingAllText(root);
+}
+
+const RenderBlock* TextAutosizer::maxClusterWidthProvider(const Supercluster* supercluster, const RenderBlock* currentRoot) const
+{
+ const RenderBlock* result = clusterWidthProvider(currentRoot);
+ float maxWidth = widthFromBlock(result);
+
+ const BlockSet* roots = supercluster->m_roots;
+ for (BlockSet::iterator it = roots->begin(); it != roots->end(); ++it) {
+ const RenderBlock* widthProvider = clusterWidthProvider(*it);
+ if (widthProvider->needsLayout())
+ continue;
+ float width = widthFromBlock(widthProvider);
+ if (width > maxWidth) {
+ maxWidth = width;
+ result = widthProvider;
}
- descendant = nextInPreOrderSkippingDescendantsOfContainers(descendant, container);
}
- return false;
+ RELEASE_ASSERT(result);
+ return result;
}
-void TextAutosizer::measureDescendantTextWidth(const RenderBlock* container, TextAutosizingClusterInfo& clusterInfo, float minTextWidth, float& textWidth)
+float TextAutosizer::widthFromBlock(const RenderBlock* block) const
{
- bool skipLocalText = !containerShouldBeAutosized(container);
-
- RenderObject* descendant = nextInPreOrderSkippingDescendantsOfContainers(container, container);
- while (descendant) {
- if (!skipLocalText && descendant->isText()) {
- textWidth += toRenderText(descendant)->renderedTextLength() * descendant->style()->specifiedFontSize();
- } else if (isAutosizingContainer(descendant)) {
- RenderBlock* descendantBlock = toRenderBlock(descendant);
- if (!isAutosizingCluster(descendantBlock, clusterInfo))
- measureDescendantTextWidth(descendantBlock, clusterInfo, minTextWidth, textWidth);
+ RELEASE_ASSERT(block);
+ RELEASE_ASSERT(block->style());
+
+ if (!(block->isTable() || block->isTableCell() || block->isListItem()))
+ return block->contentLogicalWidth().toFloat();
+
+ if (!block->containingBlock())
+ return 0;
+
+ // Tables may be inflated before computing their preferred widths. Try several methods to
+ // obtain a width, and fall back on a containing block's width.
+ for (; block; block = block->containingBlock()) {
+ float width;
+ Length specifiedWidth = block->isTableCell()
+ ? toRenderTableCell(block)->styleOrColLogicalWidth() : block->style()->logicalWidth();
+ if (specifiedWidth.isFixed()) {
+ if ((width = specifiedWidth.value()) > 0)
+ return width;
}
- if (textWidth >= minTextWidth)
- return;
- descendant = nextInPreOrderSkippingDescendantsOfContainers(descendant, container);
+ if (specifiedWidth.isPercent()) {
+ if (float containerWidth = block->containingBlock()->contentLogicalWidth().toFloat()) {
+ if ((width = floatValueForLength(specifiedWidth, containerWidth)) > 0)
+ return width;
+ }
+ }
+ if ((width = block->contentLogicalWidth().toFloat()) > 0)
+ return width;
}
+ return 0;
}
-RenderObject* TextAutosizer::nextInPreOrderSkippingDescendantsOfContainers(const RenderObject* current, const RenderObject* stayWithin)
+float TextAutosizer::multiplierFromBlock(const RenderBlock* block)
{
- if (current == stayWithin || !isAutosizingContainer(current))
- return current->nextInPreOrder(stayWithin);
- return current->nextInPreOrderAfterChildren(stayWithin);
+ // If block->needsLayout() is false, it does not need to be in m_blocksThatHaveBegunLayout.
+ // This can happen during layout of a positioned object if the cluster's DBCAT is deeper
+ // than the positioned object's containing block, and wasn't marked as needing layout.
+ ASSERT(m_blocksThatHaveBegunLayout.contains(block) || !block->needsLayout());
+
+ // Block width, in CSS pixels.
+ float blockWidth = widthFromBlock(block);
+ float multiplier = m_pageInfo.m_frameWidth ? std::min(blockWidth, static_cast<float>(m_pageInfo.m_layoutWidth)) / m_pageInfo.m_frameWidth : 1.0f;
+
+ return std::max(m_pageInfo.m_baseMultiplier * multiplier, 1.0f);
}
-const RenderBlock* TextAutosizer::findDeepestBlockContainingAllText(const RenderBlock* cluster)
+const RenderBlock* TextAutosizer::deepestBlockContainingAllText(Cluster* cluster)
+{
+ if (!cluster->m_deepestBlockContainingAllText)
+ cluster->m_deepestBlockContainingAllText = deepestBlockContainingAllText(cluster->m_root);
+
+ return cluster->m_deepestBlockContainingAllText;
+}
+
+// FIXME: Refactor this to look more like TextAutosizer::deepestCommonAncestor.
+const RenderBlock* TextAutosizer::deepestBlockContainingAllText(const RenderBlock* root) const
{
size_t firstDepth = 0;
- const RenderObject* firstTextLeaf = findFirstTextLeafNotInCluster(cluster, firstDepth, FirstToLast);
+ const RenderObject* firstTextLeaf = findTextLeaf(root, firstDepth, First);
if (!firstTextLeaf)
- return cluster;
+ return root;
size_t lastDepth = 0;
- const RenderObject* lastTextLeaf = findFirstTextLeafNotInCluster(cluster, lastDepth, LastToFirst);
+ const RenderObject* lastTextLeaf = findTextLeaf(root, lastDepth, Last);
ASSERT(lastTextLeaf);
// Equalize the depths if necessary. Only one of the while loops below will get executed.
if (firstNode->isRenderBlock())
return toRenderBlock(firstNode);
- // containingBlock() should never leave the cluster, since it only skips ancestors when finding the
- // container of position:absolute/fixed blocks, and those cannot exist between a cluster and its text
- // nodes lowest common ancestor as isAutosizingCluster would have made them into their own independent
- // cluster.
- RenderBlock* containingBlock = firstNode->containingBlock();
- ASSERT(containingBlock->isDescendantOf(cluster));
+ // containingBlock() should never leave the cluster, since it only skips ancestors when finding
+ // the container of position:absolute/fixed blocks, and those cannot exist between a cluster and
+ // its text node's lowest common ancestor as isAutosizingCluster would have made them into their
+ // own independent cluster.
+ const RenderBlock* containingBlock = firstNode->containingBlock();
+ if (!containingBlock)
+ return root;
+ ASSERT(containingBlock->isDescendantOf(root));
return containingBlock;
}
-const RenderObject* TextAutosizer::findFirstTextLeafNotInCluster(const RenderObject* parent, size_t& depth, TraversalDirection direction)
+const RenderObject* TextAutosizer::findTextLeaf(const RenderObject* parent, size_t& depth, TextLeafSearch firstOrLast) const
{
- if (parent->isEmpty())
- return parent->isText() ? parent : 0;
+ // List items are treated as text due to the marker.
+ // The actual renderer for the marker (RenderListMarker) may not be in the tree yet since it is added during layout.
+ if (parent->isListItem())
+ return parent;
+
+ if (parent->isText())
+ return parent;
++depth;
- const RenderObject* child = (direction == FirstToLast) ? parent->firstChild() : parent->lastChild();
+ const RenderObject* child = (firstOrLast == First) ? parent->slowFirstChild() : parent->slowLastChild();
while (child) {
- if (!isAutosizingContainer(child) || !isIndependentDescendant(toRenderBlock(child))) {
- const RenderObject* leaf = findFirstTextLeafNotInCluster(child, depth, direction);
- if (leaf)
+ // Note: At this point clusters may not have been created for these blocks so we cannot rely
+ // on m_clusters. Instead, we use a best-guess about whether the block will become a cluster.
+ if (!classifyBlock(child, INDEPENDENT)) {
+ if (const RenderObject* leaf = findTextLeaf(child, depth, firstOrLast))
return leaf;
}
- child = (direction == FirstToLast) ? child->nextSibling() : child->previousSibling();
+ child = (firstOrLast == First) ? child->nextSibling() : child->previousSibling();
}
--depth;
return 0;
}
-namespace {
+void TextAutosizer::applyMultiplier(RenderObject* renderer, float multiplier, RelayoutBehavior relayoutBehavior)
+{
+ ASSERT(renderer && renderer->style());
+ 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();
+
+ switch (relayoutBehavior) {
+ case AlreadyInLayout:
+ // Don't free currentStyle until the end of the layout pass. This allows other parts of the system
+ // to safely hold raw RenderStyle* pointers during layout, e.g. BreakingContext::m_currentStyle.
+ m_stylesRetainedDuringLayout.append(currentStyle);
+
+ renderer->setStyleInternal(style.release());
+ renderer->setNeedsLayoutAndFullPaintInvalidation();
+ break;
+
+ case LayoutNeeded:
+ renderer->setStyle(style.release());
+ break;
+ }
+
+ if (multiplier != 1)
+ m_pageInfo.m_hasAutosized = true;
+}
+
+bool TextAutosizer::isWiderOrNarrowerDescendant(Cluster* cluster)
+{
+ // FIXME: Why do we return true when hasExplicitWidth returns false??
+ if (!cluster->m_parent || !hasExplicitWidth(cluster->m_root))
+ return true;
+
+ const RenderBlock* parentDeepestBlockContainingAllText = deepestBlockContainingAllText(cluster->m_parent);
+ ASSERT(m_blocksThatHaveBegunLayout.contains(cluster->m_root));
+ ASSERT(m_blocksThatHaveBegunLayout.contains(parentDeepestBlockContainingAllText));
+
+ float contentWidth = cluster->m_root->contentLogicalWidth().toFloat();
+ float clusterTextWidth = parentDeepestBlockContainingAllText->contentLogicalWidth().toFloat();
+
+ // Clusters with a root that is wider than the deepestBlockContainingAllText of their parent
+ // autosize independently of their parent.
+ if (contentWidth > clusterTextWidth)
+ return true;
+
+ // Clusters with a root that is significantly narrower than the deepestBlockContainingAllText of
+ // their parent autosize independently of their parent.
+ static float narrowWidthDifference = 200;
+ if (clusterTextWidth - contentWidth > narrowWidthDifference)
+ return true;
+
+ return false;
+}
+
+TextAutosizer::Cluster* TextAutosizer::currentCluster() const
+{
+ ASSERT_WITH_SECURITY_IMPLICATION(!m_clusterStack.isEmpty());
+ return m_clusterStack.last().get();
+}
+
+#if ENABLE(ASSERT)
+void TextAutosizer::FingerprintMapper::assertMapsAreConsistent()
+{
+ // For each fingerprint -> block mapping in m_blocksForFingerprint we should have an associated
+ // map from block -> fingerprint in m_fingerprints.
+ ReverseFingerprintMap::iterator end = m_blocksForFingerprint.end();
+ for (ReverseFingerprintMap::iterator fingerprintIt = m_blocksForFingerprint.begin(); fingerprintIt != end; ++fingerprintIt) {
+ Fingerprint fingerprint = fingerprintIt->key;
+ BlockSet* blocks = fingerprintIt->value.get();
+ for (BlockSet::iterator blockIt = blocks->begin(); blockIt != blocks->end(); ++blockIt) {
+ const RenderBlock* block = (*blockIt);
+ ASSERT(m_fingerprints.get(block) == fingerprint);
+ }
+ }
+}
+#endif
+
+void TextAutosizer::FingerprintMapper::add(const RenderObject* renderer, Fingerprint fingerprint)
+{
+ remove(renderer);
+
+ m_fingerprints.set(renderer, fingerprint);
+#if ENABLE(ASSERT)
+ assertMapsAreConsistent();
+#endif
+}
-// Compares the width of the specified cluster's roots in descending order.
-bool clusterWiderThanComparisonFn(const TextAutosizingClusterInfo& first, const TextAutosizingClusterInfo& second)
+void TextAutosizer::FingerprintMapper::addTentativeClusterRoot(const RenderBlock* block, Fingerprint fingerprint)
{
- return first.root->contentLogicalWidth() > second.root->contentLogicalWidth();
+ add(block, fingerprint);
+
+ ReverseFingerprintMap::AddResult addResult = m_blocksForFingerprint.add(fingerprint, PassOwnPtr<BlockSet>());
+ if (addResult.isNewEntry)
+ addResult.storedValue->value = adoptPtr(new BlockSet);
+ addResult.storedValue->value->add(block);
+#if ENABLE(ASSERT)
+ assertMapsAreConsistent();
+#endif
}
-} // namespace
+bool TextAutosizer::FingerprintMapper::remove(const RenderObject* renderer)
+{
+ Fingerprint fingerprint = m_fingerprints.take(renderer);
+ if (!fingerprint || !renderer->isRenderBlock())
+ return false;
+
+ ReverseFingerprintMap::iterator blocksIter = m_blocksForFingerprint.find(fingerprint);
+ if (blocksIter == m_blocksForFingerprint.end())
+ return false;
+
+ BlockSet& blocks = *blocksIter->value;
+ blocks.remove(toRenderBlock(renderer));
+ if (blocks.isEmpty())
+ m_blocksForFingerprint.remove(blocksIter);
+#if ENABLE(ASSERT)
+ assertMapsAreConsistent();
+#endif
+ return true;
+}
-void TextAutosizer::getNarrowDescendantsGroupedByWidth(const TextAutosizingClusterInfo& parentClusterInfo, Vector<Vector<TextAutosizingClusterInfo> >& groups)
+TextAutosizer::Fingerprint TextAutosizer::FingerprintMapper::get(const RenderObject* renderer)
{
- ASSERT(parentClusterInfo.blockContainingAllText);
- ASSERT(groups.isEmpty());
+ return m_fingerprints.get(renderer);
+}
- Vector<TextAutosizingClusterInfo> clusterInfos(parentClusterInfo.narrowDescendants);
- if (clusterInfos.isEmpty())
+TextAutosizer::BlockSet* TextAutosizer::FingerprintMapper::getTentativeClusterRoots(Fingerprint fingerprint)
+{
+ return m_blocksForFingerprint.get(fingerprint);
+}
+
+TextAutosizer::LayoutScope::LayoutScope(RenderBlock* block)
+ : m_textAutosizer(block->document().textAutosizer())
+ , m_block(block)
+{
+ if (!m_textAutosizer)
return;
- std::sort(clusterInfos.begin(), clusterInfos.end(), &clusterWiderThanComparisonFn);
- groups.grow(1);
+ if (m_textAutosizer->shouldHandleLayout())
+ m_textAutosizer->beginLayout(m_block);
+ else
+ m_textAutosizer = 0;
+}
+
+TextAutosizer::LayoutScope::~LayoutScope()
+{
+ if (m_textAutosizer)
+ m_textAutosizer->endLayout(m_block);
+}
- // If the width difference between two consecutive elements of |clusterInfos| is greater than
- // this empirically determined value, the next element should start a new group.
- const float maxWidthDifferenceWithinGroup = 100;
- for (size_t i = 0; i < clusterInfos.size(); ++i) {
- groups.last().append(clusterInfos[i]);
- if (i + 1 < clusterInfos.size()) {
- float currentWidth = clusterInfos[i].root->contentLogicalWidth();
- float nextWidth = clusterInfos[i + 1].root->contentLogicalWidth();
- if (currentWidth - nextWidth > maxWidthDifferenceWithinGroup)
- groups.grow(groups.size() + 1);
- }
+TextAutosizer::TableLayoutScope::TableLayoutScope(RenderTable* table)
+ : LayoutScope(table)
+{
+ if (m_textAutosizer) {
+ ASSERT(m_textAutosizer->shouldHandleLayout());
+ m_textAutosizer->inflateAutoTable(table);
+ }
+}
+
+TextAutosizer::DeferUpdatePageInfo::DeferUpdatePageInfo(Page* page)
+ : m_mainFrame(page->deprecatedLocalMainFrame())
+{
+ if (TextAutosizer* textAutosizer = m_mainFrame->document()->textAutosizer()) {
+ ASSERT(!textAutosizer->m_updatePageInfoDeferred);
+ textAutosizer->m_updatePageInfoDeferred = true;
+ }
+}
+
+TextAutosizer::DeferUpdatePageInfo::~DeferUpdatePageInfo()
+{
+ if (TextAutosizer* textAutosizer = m_mainFrame->document()->textAutosizer()) {
+ ASSERT(textAutosizer->m_updatePageInfoDeferred);
+ textAutosizer->m_updatePageInfoDeferred = false;
+ textAutosizer->updatePageInfoInAllFrames();
}
}
-} // namespace WebCore
+float TextAutosizer::computeAutosizedFontSize(float specifiedSize, float multiplier)
+{
+ // Somewhat arbitrary "pleasant" font size.
+ const float pleasantSize = 16;
+
+ // Multiply fonts that the page author has specified to be larger than
+ // pleasantSize by less and less, until huge fonts are not increased at all.
+ // For specifiedSize between 0 and pleasantSize we directly apply the
+ // multiplier; hence for specifiedSize == pleasantSize, computedSize will be
+ // multiplier * pleasantSize. For greater specifiedSizes we want to
+ // gradually fade out the multiplier, so for every 1px increase in
+ // specifiedSize beyond pleasantSize we will only increase computedSize
+ // by gradientAfterPleasantSize px until we meet the
+ // computedSize = specifiedSize line, after which we stay on that line (so
+ // then every 1px increase in specifiedSize increases computedSize by 1px).
+ const float gradientAfterPleasantSize = 0.5;
+
+ float computedSize;
+ if (specifiedSize <= pleasantSize) {
+ computedSize = multiplier * specifiedSize;
+ } else {
+ computedSize = multiplier * pleasantSize + gradientAfterPleasantSize * (specifiedSize - pleasantSize);
+ if (computedSize < specifiedSize)
+ computedSize = specifiedSize;
+ }
+ return computedSize;
+}
+
+void TextAutosizer::trace(Visitor* visitor)
+{
+ visitor->trace(m_document);
+}
+
+} // namespace blink
projects / platform / framework / web / crosswalk.git / blobdiff