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/*
* Copyright (C) 2007, 2013 Apple 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:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. 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.
*
* THIS SOFTWARE IS PROVIDED BY APPLE INC. ``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 APPLE INC. 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 "RenderLayoutState.h"
#include "RenderFragmentedFlow.h"
#include "RenderInline.h"
#include "RenderLayer.h"
#include "RenderMultiColumnFlow.h"
#include "RenderView.h"
#include <wtf/WeakPtr.h>
namespace WebCore {
RenderLayoutState::RenderLayoutState(RenderElement& renderer, IsPaginated isPaginated)
: m_clipped(false)
, m_isPaginated(isPaginated == IsPaginated::Yes)
, m_pageLogicalHeightChanged(false)
#if ASSERT_ENABLED
, m_layoutDeltaXSaturated(false)
, m_layoutDeltaYSaturated(false)
, m_renderer(&renderer)
#endif
{
if (RenderElement* container = renderer.container()) {
FloatPoint absContentPoint = container->localToAbsolute(FloatPoint(), UseTransforms);
m_paintOffset = LayoutSize(absContentPoint.x(), absContentPoint.y());
if (container->hasNonVisibleOverflow()) {
m_clipped = true;
auto& containerBox = downcast<RenderBox>(*container);
m_clipRect = LayoutRect(toLayoutPoint(m_paintOffset), containerBox.cachedSizeForOverflowClip());
m_paintOffset -= toLayoutSize(containerBox.scrollPosition());
}
}
if (m_isPaginated) {
// This is just a flag for known page height (see RenderBlockFlow::checkForPaginationLogicalHeightChange).
m_pageLogicalHeight = 1;
}
}
RenderLayoutState::RenderLayoutState(const FrameViewLayoutContext::LayoutStateStack& layoutStateStack, RenderBox& renderer, const LayoutSize& offset, LayoutUnit pageLogicalHeight, bool pageLogicalHeightChanged)
: m_clipped(false)
, m_isPaginated(false)
, m_pageLogicalHeightChanged(false)
#if ASSERT_ENABLED
, m_layoutDeltaXSaturated(false)
, m_layoutDeltaYSaturated(false)
, m_renderer(&renderer)
#endif
{
if (!layoutStateStack.isEmpty()) {
auto& ancestor = *layoutStateStack.last().get();
computeOffsets(ancestor, renderer, offset);
computeClipRect(ancestor, renderer);
}
computePaginationInformation(layoutStateStack, renderer, pageLogicalHeight, pageLogicalHeightChanged);
}
void RenderLayoutState::computeOffsets(const RenderLayoutState& ancestor, RenderBox& renderer, LayoutSize offset)
{
bool fixed = renderer.isFixedPositioned();
if (fixed) {
FloatPoint fixedOffset = renderer.view().localToAbsolute(FloatPoint(), IsFixed);
m_paintOffset = LayoutSize(fixedOffset.x(), fixedOffset.y()) + offset;
} else
m_paintOffset = ancestor.paintOffset() + offset;
if (renderer.isOutOfFlowPositioned() && !fixed) {
if (auto* container = renderer.container()) {
if (container->isInFlowPositioned() && is<RenderInline>(*container))
m_paintOffset += downcast<RenderInline>(*container).offsetForInFlowPositionedInline(&renderer);
}
}
m_layoutOffset = m_paintOffset;
if (renderer.isInFlowPositioned() && renderer.hasLayer())
m_paintOffset += renderer.layer()->offsetForInFlowPosition();
if (renderer.hasNonVisibleOverflow())
m_paintOffset -= toLayoutSize(renderer.scrollPosition());
m_layoutDelta = ancestor.layoutDelta();
#if ASSERT_ENABLED
m_layoutDeltaXSaturated = ancestor.m_layoutDeltaXSaturated;
m_layoutDeltaYSaturated = ancestor.m_layoutDeltaYSaturated;
#endif
}
void RenderLayoutState::computeClipRect(const RenderLayoutState& ancestor, RenderBox& renderer)
{
m_clipped = !renderer.isFixedPositioned() && ancestor.isClipped();
if (m_clipped)
m_clipRect = ancestor.clipRect();
if (!renderer.hasNonVisibleOverflow())
return;
auto paintOffsetForClipRect = toLayoutPoint(m_paintOffset + toLayoutSize(renderer.scrollPosition()));
LayoutRect clipRect(paintOffsetForClipRect + renderer.view().frameView().layoutContext().layoutDelta(), renderer.cachedSizeForOverflowClip());
if (m_clipped)
m_clipRect.intersect(clipRect);
else
m_clipRect = clipRect;
m_clipped = true;
// FIXME: <http://bugs.webkit.org/show_bug.cgi?id=13443> Apply control clip if present.
}
void RenderLayoutState::computePaginationInformation(const FrameViewLayoutContext::LayoutStateStack& layoutStateStack, RenderBox& renderer, LayoutUnit pageLogicalHeight, bool pageLogicalHeightChanged)
{
auto* ancestor = layoutStateStack.isEmpty() ? nullptr : layoutStateStack.last().get();
// If we establish a new page height, then cache the offset to the top of the first page.
// We can compare this later on to figure out what part of the page we're actually on.
if (pageLogicalHeight || renderer.isRenderFragmentedFlow()) {
m_pageLogicalHeight = pageLogicalHeight;
bool isFlipped = renderer.style().isFlippedBlocksWritingMode();
m_pageOffset = LayoutSize(m_layoutOffset.width() + (!isFlipped ? renderer.borderLeft() + renderer.paddingLeft() : renderer.borderRight() + renderer.paddingRight()), m_layoutOffset.height() + (!isFlipped ? renderer.borderTop() + renderer.paddingTop() : renderer.borderBottom() + renderer.paddingBottom()));
m_pageLogicalHeightChanged = pageLogicalHeightChanged;
m_isPaginated = true;
} else if (ancestor) {
// If we don't establish a new page height, then propagate the old page height and offset down.
m_pageLogicalHeight = ancestor->pageLogicalHeight();
m_pageLogicalHeightChanged = ancestor->pageLogicalHeightChanged();
m_pageOffset = ancestor->pageOffset();
// Disable pagination for objects we don't support. For now this includes overflow:scroll/auto, inline blocks and writing mode roots.
if (renderer.isUnsplittableForPagination()) {
m_pageLogicalHeight = 0;
m_isPaginated = false;
} else
m_isPaginated = m_pageLogicalHeight || renderer.enclosingFragmentedFlow();
}
// Propagate line grid information.
if (ancestor)
propagateLineGridInfo(*ancestor, renderer);
if (lineGrid() && (lineGrid()->style().writingMode() == renderer.style().writingMode()) && is<RenderMultiColumnFlow>(renderer))
computeLineGridPaginationOrigin(downcast<RenderMultiColumnFlow>(renderer));
// If we have a new grid to track, then add it to our set.
if (renderer.style().lineGrid() != RenderStyle::initialLineGrid() && is<RenderBlockFlow>(renderer))
establishLineGrid(layoutStateStack, downcast<RenderBlockFlow>(renderer));
}
LayoutUnit RenderLayoutState::pageLogicalOffset(RenderBox* child, LayoutUnit childLogicalOffset) const
{
if (child->isHorizontalWritingMode())
return m_layoutOffset.height() + childLogicalOffset - m_pageOffset.height();
return m_layoutOffset.width() + childLogicalOffset - m_pageOffset.width();
}
void RenderLayoutState::computeLineGridPaginationOrigin(const RenderMultiColumnFlow& multicol)
{
if (!isPaginated() || !pageLogicalHeight())
return;
if (!multicol.progressionIsInline())
return;
// We need to cache a line grid pagination origin so that we understand how to reset the line grid
// at the top of each column.
// Get the current line grid and offset.
ASSERT(m_lineGrid);
// Get the hypothetical line box used to establish the grid.
auto* lineGridBox = m_lineGrid->lineGridBox();
if (!lineGridBox)
return;
// Now determine our position on the grid. Our baseline needs to be adjusted to the nearest baseline multiple
// as established by the line box.
// FIXME: Need to handle crazy line-box-contain values that cause the root line box to not be considered. I assume
// the grid should honor line-box-contain.
bool isHorizontalWritingMode = m_lineGrid->isHorizontalWritingMode();
LayoutUnit lineGridBlockOffset = isHorizontalWritingMode ? m_lineGridOffset.height() : m_lineGridOffset.width();
LayoutUnit firstLineTopWithLeading = lineGridBlockOffset + lineGridBox->lineBoxTop();
LayoutUnit pageLogicalTop = isHorizontalWritingMode ? m_pageOffset.height() : m_pageOffset.width();
if (pageLogicalTop <= firstLineTopWithLeading)
return;
// Shift to the next highest line grid multiple past the page logical top. Cache the delta
// between this new value and the page logical top as the pagination origin.
auto lineBoxHeight = lineGridBox->lineBoxHeight();
if (!roundToInt(lineBoxHeight))
return;
LayoutUnit remainder = roundToInt(pageLogicalTop - firstLineTopWithLeading) % roundToInt(lineBoxHeight);
LayoutUnit paginationDelta = lineBoxHeight - remainder;
if (isHorizontalWritingMode)
m_lineGridPaginationOrigin.setHeight(paginationDelta);
else
m_lineGridPaginationOrigin.setWidth(paginationDelta);
}
void RenderLayoutState::propagateLineGridInfo(const RenderLayoutState& ancestor, RenderBox& renderer)
{
// Disable line grids for objects we don't support. For now this includes overflow:scroll/auto, inline blocks and
// writing mode roots.
if (renderer.isUnsplittableForPagination())
return;
m_lineGrid = ancestor.lineGrid();
m_lineGridOffset = ancestor.lineGridOffset();
m_lineGridPaginationOrigin = ancestor.lineGridPaginationOrigin();
}
void RenderLayoutState::establishLineGrid(const FrameViewLayoutContext::LayoutStateStack& layoutStateStack, RenderBlockFlow& renderer)
{
// First check to see if this grid has been established already.
if (m_lineGrid) {
if (m_lineGrid->style().lineGrid() == renderer.style().lineGrid())
return;
auto* currentGrid = m_lineGrid.get();
for (int i = layoutStateStack.size() - 1; i >= 0; --i) {
auto& currentState = *layoutStateStack[i].get();
if (currentState.m_lineGrid == currentGrid)
continue;
currentGrid = currentState.lineGrid();
if (!currentGrid)
break;
if (currentGrid->style().lineGrid() == renderer.style().lineGrid()) {
m_lineGrid = currentGrid;
m_lineGridOffset = currentState.m_lineGridOffset;
return;
}
}
}
// We didn't find an already-established grid with this identifier. Our render object establishes the grid.
m_lineGrid = renderer;
m_lineGridOffset = m_layoutOffset;
}
void RenderLayoutState::addLayoutDelta(LayoutSize delta)
{
m_layoutDelta += delta;
#if ASSERT_ENABLED
m_layoutDeltaXSaturated |= m_layoutDelta.width() == LayoutUnit::max() || m_layoutDelta.width() == LayoutUnit::min();
m_layoutDeltaYSaturated |= m_layoutDelta.height() == LayoutUnit::max() || m_layoutDelta.height() == LayoutUnit::min();
#endif
}
#if ASSERT_ENABLED
bool RenderLayoutState::layoutDeltaMatches(LayoutSize delta) const
{
return (delta.width() == m_layoutDelta.width() || m_layoutDeltaXSaturated) && (delta.height() == m_layoutDelta.height() || m_layoutDeltaYSaturated);
}
#endif
LayoutStateMaintainer::LayoutStateMaintainer(RenderBox& root, LayoutSize offset, bool disablePaintOffsetCache, LayoutUnit pageHeight, bool pageHeightChanged)
: m_context(root.view().frameView().layoutContext())
, m_paintOffsetCacheIsDisabled(disablePaintOffsetCache)
{
m_didPushLayoutState = m_context.pushLayoutState(root, offset, pageHeight, pageHeightChanged);
if (m_didPushLayoutState && m_paintOffsetCacheIsDisabled)
m_context.disablePaintOffsetCache();
}
LayoutStateMaintainer::~LayoutStateMaintainer()
{
if (!m_didPushLayoutState)
return;
m_context.popLayoutState();
if (m_paintOffsetCacheIsDisabled)
m_context.enablePaintOffsetCache();
}
LayoutStateDisabler::LayoutStateDisabler(FrameViewLayoutContext& context)
: m_context(context)
{
m_context.disablePaintOffsetCache();
}
LayoutStateDisabler::~LayoutStateDisabler()
{
m_context.enablePaintOffsetCache();
}
static bool shouldDisablePaintOffsetCacheForSubtree(RenderElement& subtreeLayoutRoot)
{
for (auto* renderer = &subtreeLayoutRoot; renderer; renderer = renderer->container()) {
if (renderer->hasTransform() || renderer->hasReflection())
return true;
}
return false;
}
SubtreeLayoutStateMaintainer::SubtreeLayoutStateMaintainer(RenderElement* subtreeLayoutRoot)
{
if (subtreeLayoutRoot) {
m_context = &subtreeLayoutRoot->view().frameView().layoutContext();
m_context->pushLayoutState(*subtreeLayoutRoot);
if (shouldDisablePaintOffsetCacheForSubtree(*subtreeLayoutRoot)) {
m_context->disablePaintOffsetCache();
m_didDisablePaintOffsetCache = true;
}
}
}
SubtreeLayoutStateMaintainer::~SubtreeLayoutStateMaintainer()
{
if (m_context) {
m_context->popLayoutState();
if (m_didDisablePaintOffsetCache)
m_context->enablePaintOffsetCache();
}
}
PaginatedLayoutStateMaintainer::PaginatedLayoutStateMaintainer(RenderBlockFlow& flow)
: m_context(flow.view().frameView().layoutContext())
, m_pushed(m_context.pushLayoutStateForPaginationIfNeeded(flow))
{
}
PaginatedLayoutStateMaintainer::~PaginatedLayoutStateMaintainer()
{
if (m_pushed)
m_context.popLayoutState();
}
} // namespace WebCore