void RootFrameViewport::distributeScrollBetweenViewports(const DoublePoint& offset, ScrollType scrollType, ScrollBehavior behavior)
{
// Make sure we use the scroll positions as reported by each viewport's ScrollAnimatorBase, since its
// ScrollableArea's position may have the fractional part truncated off.
DoublePoint oldPosition = scrollOffsetFromScrollAnimators();
DoubleSize delta = offset - oldPosition;
if (delta.isZero())
return;
DoublePoint targetPosition = visualViewport().clampScrollPosition(
visualViewport().scrollAnimator().currentPosition() + delta);
visualViewport().setScrollPosition(targetPosition, scrollType, behavior);
// Scroll the secondary viewport if all of the scroll was not applied to the
// primary viewport.
DoublePoint updatedPosition = layoutViewport().scrollAnimator().currentPosition() + FloatPoint(targetPosition);
DoubleSize applied = updatedPosition - oldPosition;
delta -= applied;
if (delta.isZero())
return;
targetPosition = layoutViewport().clampScrollPosition(layoutViewport().scrollAnimator().currentPosition() + delta);
layoutViewport().setScrollPosition(targetPosition, scrollType, behavior);
}
void RootFrameViewport::setScrollOffset(const DoublePoint& offset, ScrollType scrollType)
{
// Make sure we use the scroll positions as reported by each viewport's ScrollAnimator, since its
// ScrollableArea's position may have the fractional part truncated off.
DoublePoint oldPosition = scrollOffsetFromScrollAnimators();
DoubleSize delta = offset - oldPosition;
if (delta.isZero())
return;
ScrollableArea& primary = !m_invertScrollOrder ? layoutViewport() : visualViewport();
ScrollableArea& secondary = !m_invertScrollOrder ? visualViewport() : layoutViewport();
DoublePoint targetPosition = primary.clampScrollPosition(primary.scrollAnimator()->currentPosition() + delta);
primary.setScrollPosition(targetPosition, scrollType);
DoubleSize applied = scrollOffsetFromScrollAnimators() - oldPosition;
delta -= applied;
if (delta.isZero())
return;
targetPosition = secondary.clampScrollPosition(secondary.scrollAnimator()->currentPosition() + delta);
secondary.setScrollPosition(targetPosition, scrollType);
}
static PassRefPtr<TransformPaintPropertyNode> createScrollTranslationIfNeeded(const LayoutObject& object, PaintPropertyTreeBuilderContext& context)
{
if (!object.isBoxModelObject() || !object.hasOverflowClip())
return nullptr;
PaintLayer* layer = toLayoutBoxModelObject(object).layer();
ASSERT(layer);
DoubleSize scrollOffset = layer->scrollableArea()->scrollOffset();
if (scrollOffset.isZero() && !layer->scrollsOverflow())
return nullptr;
RefPtr<TransformPaintPropertyNode> newTransformNodeForScrollTranslation = TransformPaintPropertyNode::create(
TransformationMatrix().translate(-scrollOffset.width(), -scrollOffset.height()),
FloatPoint3D(), context.currentTransform);
context.currentTransform = newTransformNodeForScrollTranslation.get();
return newTransformNodeForScrollTranslation.release();
}
void PaintPropertyTreeBuilder::updateScrollTranslation(const LayoutObject& object, PaintPropertyTreeBuilderContext& context)
{
if (!object.isBoxModelObject() || !object.hasOverflowClip())
return;
PaintLayer* layer = toLayoutBoxModelObject(object).layer();
ASSERT(layer);
DoubleSize scrollOffset = layer->getScrollableArea()->scrollOffset();
if (scrollOffset.isZero() && !layer->scrollsOverflow())
return;
RefPtr<TransformPaintPropertyNode> scrollTranslation = TransformPaintPropertyNode::create(
TransformationMatrix().translate(-scrollOffset.width(), -scrollOffset.height()),
FloatPoint3D(),
context.currentTransform);
context.currentTransform = scrollTranslation.get();
object.getMutableForPainting().ensureObjectPaintProperties().setScrollTranslation(scrollTranslation.release());
}
