int RenderBoxModelObject::pixelSnappedOffsetHeight() const
{
return snapSizeToPixel(offsetHeight(), offsetTop());
}
IntSize pixelSnappedIntSize(const FractionalLayoutSize& s, const FractionalLayoutPoint& p)
{
return IntSize(snapSizeToPixel(s.width(), p.x()), snapSizeToPixel(s.height(), p.y()));
}
int RenderBoxModelObject::pixelSnappedOffsetWidth() const
{
return snapSizeToPixel(offsetWidth(), offsetLeft());
}
int RenderLayerScrollableArea::pixelSnappedScrollHeight() const
{
return snapSizeToPixel(scrollHeight(), box().clientTop() + box().y());
}
int RenderLayerScrollableArea::pixelSnappedScrollWidth() const
{
return snapSizeToPixel(scrollWidth(), box().clientLeft() + box().x());
}
TEST(LayoutUnitTest, LayoutUnitSnapSizeToPixel) {
EXPECT_EQ(1, snapSizeToPixel(LayoutUnit(1), LayoutUnit(0)));
EXPECT_EQ(1, snapSizeToPixel(LayoutUnit(1), LayoutUnit(0.5)));
EXPECT_EQ(2, snapSizeToPixel(LayoutUnit(1.5), LayoutUnit(0)));
EXPECT_EQ(2, snapSizeToPixel(LayoutUnit(1.5), LayoutUnit(0.49)));
EXPECT_EQ(1, snapSizeToPixel(LayoutUnit(1.5), LayoutUnit(0.5)));
EXPECT_EQ(1, snapSizeToPixel(LayoutUnit(1.5), LayoutUnit(0.75)));
EXPECT_EQ(1, snapSizeToPixel(LayoutUnit(1.5), LayoutUnit(0.99)));
EXPECT_EQ(2, snapSizeToPixel(LayoutUnit(1.5), LayoutUnit(1)));
EXPECT_EQ(0, snapSizeToPixel(LayoutUnit(0.5), LayoutUnit(1.5)));
EXPECT_EQ(0, snapSizeToPixel(LayoutUnit(0.99), LayoutUnit(1.5)));
EXPECT_EQ(1, snapSizeToPixel(LayoutUnit(1.0), LayoutUnit(1.5)));
EXPECT_EQ(1, snapSizeToPixel(LayoutUnit(1.49), LayoutUnit(1.5)));
EXPECT_EQ(1, snapSizeToPixel(LayoutUnit(1.5), LayoutUnit(1.5)));
EXPECT_EQ(101, snapSizeToPixel(LayoutUnit(100.5), LayoutUnit(100)));
EXPECT_EQ(intMaxForLayoutUnit,
snapSizeToPixel(LayoutUnit(intMaxForLayoutUnit), LayoutUnit(0.3)));
EXPECT_EQ(intMinForLayoutUnit,
snapSizeToPixel(LayoutUnit(intMinForLayoutUnit), LayoutUnit(-0.3)));
}
void BackgroundImageGeometry::calculate(
const LayoutBoxModelObject& obj,
const LayoutBoxModelObject* paintContainer,
const GlobalPaintFlags globalPaintFlags,
const FillLayer& fillLayer,
const LayoutRect& paintRect) {
LayoutUnit left;
LayoutUnit top;
LayoutSize positioningAreaSize;
bool isLayoutView = obj.isLayoutView();
const LayoutBox* rootBox = nullptr;
if (isLayoutView) {
// It is only possible reach here when root element has a box.
Element* documentElement = obj.document().documentElement();
DCHECK(documentElement);
DCHECK(documentElement->layoutObject());
DCHECK(documentElement->layoutObject()->isBox());
rootBox = toLayoutBox(documentElement->layoutObject());
}
const LayoutBoxModelObject& positioningBox =
isLayoutView ? static_cast<const LayoutBoxModelObject&>(*rootBox) : obj;
// Determine the background positioning area and set destRect to the
// background painting area. destRect will be adjusted later if the
// background is non-repeating.
// FIXME: transforms spec says that fixed backgrounds behave like scroll
// inside transforms.
bool fixedAttachment = fillLayer.attachment() == FixedBackgroundAttachment;
if (RuntimeEnabledFeatures::fastMobileScrollingEnabled()) {
// As a side effect of an optimization to blit on scroll, we do not honor
// the CSS property "background-attachment: fixed" because it may result in
// rendering artifacts. Note, these artifacts only appear if we are blitting
// on scroll of a page that has fixed background images.
fixedAttachment = false;
}
if (!fixedAttachment) {
setDestRect(paintRect);
LayoutUnit right;
LayoutUnit bottom;
// Scroll and Local.
if (fillLayer.origin() != BorderFillBox) {
left = LayoutUnit(positioningBox.borderLeft());
right = LayoutUnit(positioningBox.borderRight());
top = LayoutUnit(positioningBox.borderTop());
bottom = LayoutUnit(positioningBox.borderBottom());
if (fillLayer.origin() == ContentFillBox) {
left += positioningBox.paddingLeft();
right += positioningBox.paddingRight();
top += positioningBox.paddingTop();
bottom += positioningBox.paddingBottom();
}
}
if (isLayoutView) {
// The background of the box generated by the root element covers the
// entire canvas and will be painted by the view object, but the we should
// still use the root element box for positioning.
positioningAreaSize =
rootBox->size() - LayoutSize(left + right, top + bottom),
rootBox->location();
// The input paint rect is specified in root element local coordinate
// (i.e. a transform is applied on the context for painting), and is
// expanded to cover the whole canvas. Since left/top is relative to the
// paint rect, we need to offset them back.
left -= paintRect.x();
top -= paintRect.y();
} else {
positioningAreaSize =
paintRect.size() - LayoutSize(left + right, top + bottom);
}
} else {
setHasNonLocalGeometry();
LayoutRect viewportRect = obj.viewRect();
if (fixedBackgroundPaintsInLocalCoordinates(obj, globalPaintFlags)) {
viewportRect.setLocation(LayoutPoint());
} else {
if (FrameView* frameView = obj.view()->frameView())
viewportRect.setLocation(IntPoint(frameView->scrollOffsetInt()));
// Compensate the translations created by ScrollRecorders.
// TODO(trchen): Fix this for SP phase 2. crbug.com/529963.
viewportRect.moveBy(
accumulatedScrollOffsetForFixedBackground(obj, paintContainer));
}
if (paintContainer)
viewportRect.moveBy(
LayoutPoint(-paintContainer->localToAbsolute(FloatPoint())));
setDestRect(viewportRect);
positioningAreaSize = destRect().size();
}
LayoutSize fillTileSize(
calculateFillTileSize(positioningBox, fillLayer, positioningAreaSize));
// It's necessary to apply the heuristic here prior to any further
// calculations to avoid incorrectly using sub-pixel values that won't be
// present in the painted tile.
setTileSize(applySubPixelHeuristicToImageSize(fillTileSize, m_destRect));
EFillRepeat backgroundRepeatX = fillLayer.repeatX();
EFillRepeat backgroundRepeatY = fillLayer.repeatY();
LayoutUnit unsnappedAvailableWidth =
positioningAreaSize.width() - fillTileSize.width();
LayoutUnit unsnappedAvailableHeight =
positioningAreaSize.height() - fillTileSize.height();
positioningAreaSize =
LayoutSize(snapSizeToPixel(positioningAreaSize.width(), m_destRect.x()),
snapSizeToPixel(positioningAreaSize.height(), m_destRect.y()));
LayoutUnit availableWidth = positioningAreaSize.width() - tileSize().width();
LayoutUnit availableHeight =
positioningAreaSize.height() - tileSize().height();
LayoutUnit computedXPosition =
roundedMinimumValueForLength(fillLayer.xPosition(), availableWidth);
if (backgroundRepeatX == RoundFill &&
positioningAreaSize.width() > LayoutUnit() &&
fillTileSize.width() > LayoutUnit()) {
int nrTiles = std::max(
1, roundToInt(positioningAreaSize.width() / fillTileSize.width()));
LayoutUnit roundedWidth = positioningAreaSize.width() / nrTiles;
// Maintain aspect ratio if background-size: auto is set
if (fillLayer.size().size.height().isAuto() &&
backgroundRepeatY != RoundFill) {
fillTileSize.setHeight(fillTileSize.height() * roundedWidth /
fillTileSize.width());
}
fillTileSize.setWidth(roundedWidth);
setTileSize(applySubPixelHeuristicToImageSize(fillTileSize, m_destRect));
setPhaseX(tileSize().width()
? LayoutUnit(roundf(
tileSize().width() -
fmodf((computedXPosition + left), tileSize().width())))
: LayoutUnit());
setSpaceSize(LayoutSize());
}
LayoutUnit computedYPosition =
roundedMinimumValueForLength(fillLayer.yPosition(), availableHeight);
if (backgroundRepeatY == RoundFill &&
positioningAreaSize.height() > LayoutUnit() &&
fillTileSize.height() > LayoutUnit()) {
int nrTiles = std::max(
1, roundToInt(positioningAreaSize.height() / fillTileSize.height()));
LayoutUnit roundedHeight = positioningAreaSize.height() / nrTiles;
// Maintain aspect ratio if background-size: auto is set
if (fillLayer.size().size.width().isAuto() &&
backgroundRepeatX != RoundFill) {
fillTileSize.setWidth(fillTileSize.width() * roundedHeight /
fillTileSize.height());
}
fillTileSize.setHeight(roundedHeight);
setTileSize(applySubPixelHeuristicToImageSize(fillTileSize, m_destRect));
setPhaseY(tileSize().height()
? LayoutUnit(roundf(
tileSize().height() -
fmodf((computedYPosition + top), tileSize().height())))
: LayoutUnit());
setSpaceSize(LayoutSize());
}
if (backgroundRepeatX == RepeatFill) {
setRepeatX(fillLayer, fillTileSize.width(), availableWidth,
unsnappedAvailableWidth, left);
} else if (backgroundRepeatX == SpaceFill &&
tileSize().width() > LayoutUnit()) {
LayoutUnit space = getSpaceBetweenImageTiles(positioningAreaSize.width(),
tileSize().width());
if (space >= LayoutUnit())
setSpaceX(space, availableWidth, left);
else
backgroundRepeatX = NoRepeatFill;
}
if (backgroundRepeatX == NoRepeatFill) {
LayoutUnit xOffset = fillLayer.backgroundXOrigin() == RightEdge
? availableWidth - computedXPosition
: computedXPosition;
setNoRepeatX(left + xOffset);
}
if (backgroundRepeatY == RepeatFill) {
setRepeatY(fillLayer, fillTileSize.height(), availableHeight,
unsnappedAvailableHeight, top);
} else if (backgroundRepeatY == SpaceFill &&
tileSize().height() > LayoutUnit()) {
LayoutUnit space = getSpaceBetweenImageTiles(positioningAreaSize.height(),
tileSize().height());
if (space >= LayoutUnit())
setSpaceY(space, availableHeight, top);
else
backgroundRepeatY = NoRepeatFill;
}
if (backgroundRepeatY == NoRepeatFill) {
LayoutUnit yOffset = fillLayer.backgroundYOrigin() == BottomEdge
? availableHeight - computedYPosition
: computedYPosition;
setNoRepeatY(top + yOffset);
}
if (fixedAttachment)
useFixedAttachment(paintRect.location());
// Clip the final output rect to the paint rect
m_destRect.intersect(paintRect);
// Snap as-yet unsnapped values.
setDestRect(LayoutRect(pixelSnappedIntRect(m_destRect)));
}