void QtViewportInteractionEngine::zoomToAreaGestureEnded(const QPointF& touchPoint, const QRectF& targetArea)
{
if (!targetArea.isValid())
return;
if (scrollAnimationActive() || scaleAnimationActive())
return;
const int margin = 10; // We want at least a little bit or margin.
QRectF endArea = itemRectFromCSS(targetArea.adjusted(-margin, -margin, margin, margin));
const QRectF viewportRect = m_viewport->boundingRect();
qreal targetCSSScale = cssScaleFromItem(viewportRect.size().width() / endArea.size().width());
qreal endItemScale = itemScaleFromCSS(innerBoundedCSSScale(qMin(targetCSSScale, qreal(2.5))));
// We want to end up with the target area filling the whole width of the viewport (if possible),
// and centralized vertically where the user requested zoom. Thus our hotspot is the center of
// the targetArea x-wise and the requested zoom position, y-wise.
const QPointF hotspot = QPointF(endArea.center().x(), touchPoint.y() * m_constraints.devicePixelRatio);
const QPointF viewportHotspot = viewportRect.center();
QPointF endPosition = hotspot * endItemScale - viewportHotspot;
QRectF endPosRange = computePosRangeForItemAtScale(endItemScale);
endPosition = boundPosition(endPosRange.topLeft(), endPosition, endPosRange.bottomRight());
QRectF endVisibleContentRect(endPosition / endItemScale, viewportRect.size() / endItemScale);
animateItemRectVisible(endVisibleContentRect);
}
void QtViewportHandler::pinchGestureRequestUpdate(const QPointF& pinchCenterInViewportCoordinates, qreal totalScaleFactor)
{
ASSERT(m_suspendCount);
if (!m_allowsUserScaling)
return;
// Changes of the center position should move the page even if the zoom factor
// does not change.
const qreal cssScale = cssScaleFromItem(m_pinchStartScale * totalScaleFactor);
// Allow zooming out beyond mimimum scale on pages that do not explicitly disallow it.
const qreal targetCSSScale = outerBoundedCSSScale(cssScale);
scaleContent(m_viewportItem->mapToWebContent(pinchCenterInViewportCoordinates), targetCSSScale);
const QPointF positionDiff = pinchCenterInViewportCoordinates - m_lastPinchCenterInViewportCoordinates;
m_lastPinchCenterInViewportCoordinates = pinchCenterInViewportCoordinates;
m_viewportItem->setContentPos(m_viewportItem->contentPos() - positionDiff);
}
qreal QtViewportHandler::currentCSSScale() const
{
return cssScaleFromItem(m_pageItem->contentsScale());
}
void QtViewportHandler::zoomToAreaGestureEnded(const QPointF& touchPoint, const QRectF& targetArea)
{
// This can only happen as a result of a user interaction.
ASSERT(m_hadUserInteraction);
if (!targetArea.isValid())
return;
if (m_suspendCount)
return;
const int margin = 10; // We want at least a little bit of margin.
QRectF endArea = itemRectFromCSS(targetArea.adjusted(-margin, -margin, margin, margin));
const QRectF viewportRect = m_viewportItem->boundingRect();
qreal targetCSSScale = viewportRect.size().width() / endArea.size().width();
qreal endCSSScale = innerBoundedCSSScale(qMin(targetCSSScale, qreal(2.5)));
qreal endItemScale = itemScaleFromCSS(endCSSScale);
qreal currentScale = m_pageItem->contentsScale();
// We want to end up with the target area filling the whole width of the viewport (if possible),
// and centralized vertically where the user requested zoom. Thus our hotspot is the center of
// the targetArea x-wise and the requested zoom position, y-wise.
const QPointF hotspot = QPointF(endArea.center().x(), itemCoordFromCSS(touchPoint.y()));
const QPointF viewportHotspot = viewportRect.center();
QPointF endPosition = hotspot * endCSSScale - viewportHotspot;
QRectF endPosRange = computePosRangeForPageItemAtScale(endItemScale);
endPosition = boundPosition(endPosRange.topLeft(), endPosition, endPosRange.bottomRight());
QRectF endVisibleContentRect(endPosition / endItemScale, viewportRect.size() / endItemScale);
enum { ZoomIn, ZoomBack, ZoomOut, NoZoom } zoomAction = ZoomIn;
if (!m_scaleStack.isEmpty()) {
// Zoom back out if attempting to scale to the same current scale, or
// attempting to continue scaling out from the inner most level.
// Use fuzzy compare with a fixed error to be able to deal with largish differences due to pixel rounding.
if (fuzzyCompare(endItemScale, currentScale, 0.01)) {
// If moving the viewport would expose more of the targetRect and move at least 40 pixels, update position but do not scale out.
QRectF currentContentRect(m_viewportItem->contentPos() / currentScale, viewportRect.size() / currentScale);
QRectF targetIntersection = endVisibleContentRect.intersected(targetArea);
if (!currentContentRect.contains(targetIntersection) && (qAbs(endVisibleContentRect.top() - currentContentRect.top()) >= 40 || qAbs(endVisibleContentRect.left() - currentContentRect.left()) >= 40))
zoomAction = NoZoom;
else
zoomAction = ZoomBack;
} else if (fuzzyCompare(endItemScale, m_zoomOutScale, 0.01))
zoomAction = ZoomBack;
else if (endItemScale < currentScale)
zoomAction = ZoomOut;
}
switch (zoomAction) {
case ZoomIn:
m_scaleStack.append(ScaleStackItem(currentScale, m_viewportItem->contentPos().x()));
m_zoomOutScale = endItemScale;
break;
case ZoomBack: {
ScaleStackItem lastScale = m_scaleStack.takeLast();
endItemScale = lastScale.scale;
endCSSScale = cssScaleFromItem(lastScale.scale);
// Recalculate endPosition and bound it according to new scale.
endPosition.setY(hotspot.y() * endCSSScale - viewportHotspot.y());
endPosition.setX(lastScale.xPosition);
endPosRange = computePosRangeForPageItemAtScale(endItemScale);
endPosition = boundPosition(endPosRange.topLeft(), endPosition, endPosRange.bottomRight());
endVisibleContentRect = QRectF(endPosition / endItemScale, viewportRect.size() / endItemScale);
break;
}
case ZoomOut:
// Unstack all scale-levels deeper than the new level, so a zoom-back won't end up zooming in.
while (!m_scaleStack.isEmpty() && m_scaleStack.last().scale >= endItemScale)
m_scaleStack.removeLast();
m_zoomOutScale = endItemScale;
break;
case NoZoom:
break;
}
animatePageItemRectVisible(endVisibleContentRect);
}
qreal QtViewportInteractionEngine::currentCSSScale()
{
return cssScaleFromItem(m_content->contentsScale());
}