bool VisualViewport::magnifyScaleAroundAnchor(float magnifyDelta, const FloatPoint& anchor)
{
const float oldPageScale = scale();
const float newPageScale = frameHost().chromeClient().clampPageScaleFactorToLimits(
magnifyDelta * oldPageScale);
if (newPageScale == oldPageScale)
return false;
if (!mainFrame() || !mainFrame()->view())
return false;
// Keep the center-of-pinch anchor in a stable position over the course
// of the magnify.
FloatPoint anchorAtOldScale = anchor.scaledBy(1.f / oldPageScale);
FloatPoint anchorAtNewScale = anchor.scaledBy(1.f / newPageScale);
FloatSize anchorDelta = anchorAtOldScale - anchorAtNewScale;
// First try to use the anchor's delta to scroll the FrameView.
FloatSize anchorDeltaUnusedByScroll = anchorDelta;
if (!frameHost().settings().invertViewportScrollOrder()) {
FrameView* view = mainFrame()->view();
DoublePoint oldPosition = view->scrollPositionDouble();
view->scrollBy(DoubleSize(anchorDelta.width(), anchorDelta.height()), UserScroll);
DoublePoint newPosition = view->scrollPositionDouble();
anchorDeltaUnusedByScroll -= toFloatSize(newPosition - oldPosition);
}
// Manually bubble any remaining anchor delta up to the visual viewport.
FloatPoint newLocation(location() + anchorDeltaUnusedByScroll);
setScaleAndLocation(newPageScale, newLocation);
return true;
}
bool VisualViewport::magnifyScaleAroundAnchor(float magnifyDelta,
const FloatPoint& anchor) {
const float oldPageScale = scale();
const float newPageScale =
frameHost().chromeClient().clampPageScaleFactorToLimits(magnifyDelta *
oldPageScale);
if (newPageScale == oldPageScale)
return false;
if (!mainFrame() || !mainFrame()->view())
return false;
// Keep the center-of-pinch anchor in a stable position over the course
// of the magnify.
FloatPoint anchorAtOldScale = anchor.scaledBy(1.f / oldPageScale);
FloatPoint anchorAtNewScale = anchor.scaledBy(1.f / newPageScale);
FloatSize anchorDelta = anchorAtOldScale - anchorAtNewScale;
// First try to use the anchor's delta to scroll the FrameView.
FloatSize anchorDeltaUnusedByScroll = anchorDelta;
// Manually bubble any remaining anchor delta up to the visual viewport.
FloatPoint newLocation(FloatPoint(getScrollOffset()) +
anchorDeltaUnusedByScroll);
setScaleAndLocation(newPageScale, newLocation);
return true;
}
void VisualViewport::setScale(float scale)
{
setScaleAndLocation(scale, m_offset);
}
void VisualViewport::setLocation(const FloatPoint& newLocation)
{
setScaleAndLocation(m_scale, newLocation);
}
void VisualViewport::reset()
{
setScaleAndLocation(1, FloatPoint());
}
void VisualViewport::setScale(float scale) {
setScaleAndLocation(scale, FloatPoint(m_offset));
}
