void
APZCCallbackHelper::UpdateRootFrame(nsIDOMWindowUtils* aUtils,
FrameMetrics& aMetrics)
{
// Precondition checks
MOZ_ASSERT(aUtils);
MOZ_ASSERT(aMetrics.GetUseDisplayPortMargins());
if (aMetrics.GetScrollId() == FrameMetrics::NULL_SCROLL_ID) {
return;
}
// Set the scroll port size, which determines the scroll range. For example if
// a 500-pixel document is shown in a 100-pixel frame, the scroll port length would
// be 100, and gecko would limit the maximum scroll offset to 400 (so as to prevent
// overscroll). Note that if the content here was zoomed to 2x, the document would
// be 1000 pixels long but the frame would still be 100 pixels, and so the maximum
// scroll range would be 900. Therefore this calculation depends on the zoom applied
// to the content relative to the container.
// Note that this needs to happen before scrolling the frame (in UpdateFrameCommon),
// otherwise the scroll position may get clamped incorrectly.
CSSSize scrollPort = aMetrics.CalculateCompositedSizeInCssPixels();
aUtils->SetScrollPositionClampingScrollPortSize(scrollPort.width, scrollPort.height);
nsIContent* content = nsLayoutUtils::FindContentFor(aMetrics.GetScrollId());
ScrollFrame(content, aMetrics);
// The pres shell resolution is updated by the the async zoom since the
// last paint.
float presShellResolution = aMetrics.GetPresShellResolution()
* aMetrics.GetAsyncZoom().scale;
aUtils->SetResolutionAndScaleTo(presShellResolution, presShellResolution);
SetDisplayPortMargins(aUtils, content, aMetrics);
}
void
APZCCallbackHelper::UpdateRootFrame(FrameMetrics& aMetrics)
{
if (aMetrics.GetScrollId() == FrameMetrics::NULL_SCROLL_ID) {
return;
}
nsIContent* content = nsLayoutUtils::FindContentFor(aMetrics.GetScrollId());
if (!content) {
return;
}
nsCOMPtr<nsIPresShell> shell = GetPresShell(content);
if (!shell || aMetrics.GetPresShellId() != shell->GetPresShellId()) {
return;
}
MOZ_ASSERT(aMetrics.GetUseDisplayPortMargins());
if (gfxPrefs::APZAllowZooming()) {
// If zooming is disabled then we don't really want to let APZ fiddle
// with these things. In theory setting the resolution here should be a
// no-op, but setting the SPCSPS is bad because it can cause a stale value
// to be returned by window.innerWidth/innerHeight (see bug 1187792).
float presShellResolution = nsLayoutUtils::GetResolution(shell);
// If the pres shell resolution has changed on the content side side
// the time this repaint request was fired, consider this request out of date
// and drop it; setting a zoom based on the out-of-date resolution can have
// the effect of getting us stuck with the stale resolution.
if (presShellResolution != aMetrics.GetPresShellResolution()) {
return;
}
// Set the scroll port size, which determines the scroll range. For example if
// a 500-pixel document is shown in a 100-pixel frame, the scroll port length would
// be 100, and gecko would limit the maximum scroll offset to 400 (so as to prevent
// overscroll). Note that if the content here was zoomed to 2x, the document would
// be 1000 pixels long but the frame would still be 100 pixels, and so the maximum
// scroll range would be 900. Therefore this calculation depends on the zoom applied
// to the content relative to the container.
// Note that this needs to happen before scrolling the frame (in UpdateFrameCommon),
// otherwise the scroll position may get clamped incorrectly.
CSSSize scrollPort = aMetrics.CalculateCompositedSizeInCssPixels();
nsLayoutUtils::SetScrollPositionClampingScrollPortSize(shell, scrollPort);
// The pres shell resolution is updated by the the async zoom since the
// last paint.
presShellResolution = aMetrics.GetPresShellResolution()
* aMetrics.GetAsyncZoom().scale;
nsLayoutUtils::SetResolutionAndScaleTo(shell, presShellResolution);
}
// Do this as late as possible since scrolling can flush layout. It also
// adjusts the display port margins, so do it before we set those.
ScrollFrame(content, aMetrics);
SetDisplayPortMargins(shell, content, aMetrics);
}
void
APZCCallbackHelper::UpdateRootFrame(nsIPresShell* aPresShell,
FrameMetrics& aMetrics)
{
// Precondition checks
MOZ_ASSERT(aPresShell);
MOZ_ASSERT(aMetrics.GetUseDisplayPortMargins());
if (aMetrics.GetScrollId() == FrameMetrics::NULL_SCROLL_ID) {
return;
}
float presShellResolution = nsLayoutUtils::GetResolution(aPresShell);
// If the pres shell resolution has changed on the content side side
// the time this repaint request was fired, consider this request out of date
// and drop it; setting a zoom based on the out-of-date resolution can have
// the effect of getting us stuck with the stale resolution.
if (presShellResolution != aMetrics.GetPresShellResolution()) {
return;
}
// Set the scroll port size, which determines the scroll range. For example if
// a 500-pixel document is shown in a 100-pixel frame, the scroll port length would
// be 100, and gecko would limit the maximum scroll offset to 400 (so as to prevent
// overscroll). Note that if the content here was zoomed to 2x, the document would
// be 1000 pixels long but the frame would still be 100 pixels, and so the maximum
// scroll range would be 900. Therefore this calculation depends on the zoom applied
// to the content relative to the container.
// Note that this needs to happen before scrolling the frame (in UpdateFrameCommon),
// otherwise the scroll position may get clamped incorrectly.
CSSSize scrollPort = aMetrics.CalculateCompositedSizeInCssPixels();
nsLayoutUtils::SetScrollPositionClampingScrollPortSize(aPresShell, scrollPort);
// The pres shell resolution is updated by the the async zoom since the
// last paint.
presShellResolution = aMetrics.GetPresShellResolution()
* aMetrics.GetAsyncZoom().scale;
nsLayoutUtils::SetResolutionAndScaleTo(aPresShell, presShellResolution);
// Do this as late as possible since scrolling can flush layout. It also
// adjusts the display port margins, so do it before we set those.
nsIContent* content = nsLayoutUtils::FindContentFor(aMetrics.GetScrollId());
ScrollFrame(content, aMetrics);
SetDisplayPortMargins(aPresShell, content, aMetrics);
}
CSSRect
CalculateRectToZoomTo(const nsCOMPtr<nsIDocument>& aRootContentDocument,
const CSSPoint& aPoint)
{
// Ensure the layout information we get is up-to-date.
aRootContentDocument->FlushPendingNotifications(FlushType::Layout);
// An empty rect as return value is interpreted as "zoom out".
const CSSRect zoomOut;
nsCOMPtr<nsIPresShell> shell = aRootContentDocument->GetShell();
if (!shell) {
return zoomOut;
}
nsIScrollableFrame* rootScrollFrame = shell->GetRootScrollFrameAsScrollable();
if (!rootScrollFrame) {
return zoomOut;
}
nsCOMPtr<dom::Element> element = ElementFromPoint(shell, aPoint);
if (!element) {
return zoomOut;
}
while (element && !ShouldZoomToElement(element)) {
element = element->GetParentElement();
}
if (!element) {
return zoomOut;
}
FrameMetrics metrics = nsLayoutUtils::CalculateBasicFrameMetrics(rootScrollFrame);
CSSRect compositedArea(metrics.GetScrollOffset(), metrics.CalculateCompositedSizeInCssPixels());
const CSSCoord margin = 15;
CSSRect rect = nsLayoutUtils::GetBoundingContentRect(element, rootScrollFrame);
// If the element is taller than the visible area of the page scale
// the height of the |rect| so that it has the same aspect ratio as
// the root frame. The clipped |rect| is centered on the y value of
// the touch point. This allows tall narrow elements to be zoomed.
if (!rect.IsEmpty() && compositedArea.width > 0.0f) {
const float widthRatio = rect.width / compositedArea.width;
float targetHeight = compositedArea.height * widthRatio;
if (widthRatio < 0.9 && targetHeight < rect.height) {
const CSSPoint scrollPoint = CSSPoint::FromAppUnits(rootScrollFrame->GetScrollPosition());
float newY = aPoint.y + scrollPoint.y - (targetHeight * 0.5f);
if ((newY + targetHeight) > (rect.y + rect.height)) {
rect.y += rect.height - targetHeight;
} else if (newY > rect.y) {
rect.y = newY;
}
rect.height = targetHeight;
}
}
rect = CSSRect(std::max(metrics.GetScrollableRect().x, rect.x - margin),
rect.y,
rect.width + 2 * margin,
rect.height);
// Constrict the rect to the screen's right edge
rect.width = std::min(rect.width, metrics.GetScrollableRect().XMost() - rect.x);
// If the rect is already taking up most of the visible area and is
// stretching the width of the page, then we want to zoom out instead.
if (IsRectZoomedIn(rect, compositedArea)) {
return zoomOut;
}
CSSRect rounded(rect);
rounded.Round();
// If the block we're zooming to is really tall, and the user double-tapped
// more than a screenful of height from the top of it, then adjust the
// y-coordinate so that we center the actual point the user double-tapped
// upon. This prevents flying to the top of the page when double-tapping
// to zoom in (bug 761721). The 1.2 multiplier is just a little fuzz to
// compensate for 'rect' including horizontal margins but not vertical ones.
CSSCoord cssTapY = metrics.GetScrollOffset().y + aPoint.y;
if ((rect.height > rounded.height) && (cssTapY > rounded.y + (rounded.height * 1.2))) {
rounded.y = cssTapY - (rounded.height / 2);
}
return rounded;
}
void
APZCCallbackHelper::UpdateRootFrame(nsIDOMWindowUtils* aUtils,
FrameMetrics& aMetrics)
{
// Precondition checks
MOZ_ASSERT(aUtils);
MOZ_ASSERT(aMetrics.GetUseDisplayPortMargins());
if (aMetrics.GetScrollId() == FrameMetrics::NULL_SCROLL_ID) {
return;
}
// Set the scroll port size, which determines the scroll range. For example if
// a 500-pixel document is shown in a 100-pixel frame, the scroll port length would
// be 100, and gecko would limit the maximum scroll offset to 400 (so as to prevent
// overscroll). Note that if the content here was zoomed to 2x, the document would
// be 1000 pixels long but the frame would still be 100 pixels, and so the maximum
// scroll range would be 900. Therefore this calculation depends on the zoom applied
// to the content relative to the container.
CSSSize scrollPort = aMetrics.CalculateCompositedSizeInCssPixels();
aUtils->SetScrollPositionClampingScrollPortSize(scrollPort.width, scrollPort.height);
// Scroll the window to the desired spot
nsIScrollableFrame* sf = nsLayoutUtils::FindScrollableFrameFor(aMetrics.GetScrollId());
bool scrollUpdated = false;
CSSPoint actualScrollOffset = ScrollFrameTo(sf, aMetrics.GetScrollOffset(), scrollUpdated);
if (scrollUpdated) {
// Correct the display port due to the difference between mScrollOffset and the
// actual scroll offset.
AdjustDisplayPortForScrollDelta(aMetrics, actualScrollOffset);
} else {
// For whatever reason we couldn't update the scroll offset on the scroll frame,
// which means the data APZ used for its displayport calculation is stale. Fall
// back to a sane default behaviour. Note that we don't tile-align the recentered
// displayport because tile-alignment depends on the scroll position, and the
// scroll position here is out of our control. See bug 966507 comment 21 for a
// more detailed explanation.
RecenterDisplayPort(aMetrics);
}
aMetrics.SetScrollOffset(actualScrollOffset);
// The mZoom variable on the frame metrics stores the CSS-to-screen scale for this
// frame. This scale includes all of the (cumulative) resolutions set on the presShells
// from the root down to this frame. However, when setting the resolution, we only
// want the piece of the resolution that corresponds to this presShell, rather than
// all of the cumulative stuff, so we need to divide out the parent resolutions.
// Finally, we multiply by a ScreenToLayerScale of 1.0f because the goal here is to
// take the async zoom calculated by the APZC and tell gecko about it (turning it into
// a "sync" zoom) which will update the resolution at which the layer is painted.
ParentLayerToLayerScale presShellResolution =
aMetrics.GetZoom()
/ aMetrics.mDevPixelsPerCSSPixel
/ aMetrics.GetParentResolution()
* ScreenToLayerScale(1.0f);
aUtils->SetResolution(presShellResolution.scale, presShellResolution.scale);
// Finally, we set the displayport.
nsCOMPtr<nsIContent> content = nsLayoutUtils::FindContentFor(aMetrics.GetScrollId());
if (!content) {
return;
}
nsCOMPtr<nsIDOMElement> element = do_QueryInterface(content);
if (!element) {
return;
}
gfx::IntSize alignment = gfxPrefs::LayersTilesEnabled()
? gfx::IntSize(gfxPrefs::LayersTileWidth(), gfxPrefs::LayersTileHeight()) :
gfx::IntSize(0, 0);
LayerMargin margins = aMetrics.GetDisplayPortMargins();
aUtils->SetDisplayPortMarginsForElement(margins.left,
margins.top,
margins.right,
margins.bottom,
alignment.width,
alignment.height,
element, 0);
CSSRect baseCSS = aMetrics.CalculateCompositedRectInCssPixels();
nsRect base(baseCSS.x * nsPresContext::AppUnitsPerCSSPixel(),
baseCSS.y * nsPresContext::AppUnitsPerCSSPixel(),
baseCSS.width * nsPresContext::AppUnitsPerCSSPixel(),
baseCSS.height * nsPresContext::AppUnitsPerCSSPixel());
nsLayoutUtils::SetDisplayPortBaseIfNotSet(content, base);
}
CSSRect
CalculateRectToZoomTo(const nsCOMPtr<nsIDocument>& aRootContentDocument,
const CSSPoint& aPoint)
{
// Ensure the layout information we get is up-to-date.
aRootContentDocument->FlushPendingNotifications(Flush_Layout);
// An empty rect as return value is interpreted as "zoom out".
const CSSRect zoomOut;
nsCOMPtr<nsIPresShell> shell = aRootContentDocument->GetShell();
if (!shell) {
return zoomOut;
}
nsIScrollableFrame* rootScrollFrame = shell->GetRootScrollFrameAsScrollable();
if (!rootScrollFrame) {
return zoomOut;
}
nsCOMPtr<dom::Element> element = ElementFromPoint(shell, aPoint);
if (!element) {
return zoomOut;
}
while (element && !ShouldZoomToElement(element)) {
element = element->GetParentElement();
}
if (!element) {
return zoomOut;
}
FrameMetrics metrics = nsLayoutUtils::CalculateBasicFrameMetrics(rootScrollFrame);
CSSRect compositedArea(metrics.GetScrollOffset(), metrics.CalculateCompositedSizeInCssPixels());
const CSSCoord margin = 15;
CSSRect rect = GetBoundingContentRect(shell, element, rootScrollFrame);
rect = CSSRect(std::max(metrics.GetScrollableRect().x, rect.x - margin),
rect.y,
rect.width + 2 * margin,
rect.height);
// Constrict the rect to the screen's right edge
rect.width = std::min(rect.width, metrics.GetScrollableRect().XMost() - rect.x);
// If the rect is already taking up most of the visible area and is
// stretching the width of the page, then we want to zoom out instead.
if (IsRectZoomedIn(rect, compositedArea)) {
return zoomOut;
}
CSSRect rounded(rect);
rounded.Round();
// If the block we're zooming to is really tall, and the user double-tapped
// more than a screenful of height from the top of it, then adjust the
// y-coordinate so that we center the actual point the user double-tapped
// upon. This prevents flying to the top of the page when double-tapping
// to zoom in (bug 761721). The 1.2 multiplier is just a little fuzz to
// compensate for 'rect' including horizontal margins but not vertical ones.
CSSCoord cssTapY = metrics.GetScrollOffset().y + aPoint.y;
if ((rect.height > rounded.height) && (cssTapY > rounded.y + (rounded.height * 1.2))) {
rounded.y = cssTapY - (rounded.height / 2);
}
return rounded;
}
void
APZCCallbackHelper::UpdateRootFrame(nsIDOMWindowUtils* aUtils,
FrameMetrics& aMetrics)
{
// Precondition checks
MOZ_ASSERT(aUtils);
MOZ_ASSERT(aMetrics.GetUseDisplayPortMargins());
if (aMetrics.GetScrollId() == FrameMetrics::NULL_SCROLL_ID) {
return;
}
// Set the scroll port size, which determines the scroll range. For example if
// a 500-pixel document is shown in a 100-pixel frame, the scroll port length would
// be 100, and gecko would limit the maximum scroll offset to 400 (so as to prevent
// overscroll). Note that if the content here was zoomed to 2x, the document would
// be 1000 pixels long but the frame would still be 100 pixels, and so the maximum
// scroll range would be 900. Therefore this calculation depends on the zoom applied
// to the content relative to the container.
CSSSize scrollPort = aMetrics.CalculateCompositedSizeInCssPixels();
aUtils->SetScrollPositionClampingScrollPortSize(scrollPort.width, scrollPort.height);
// Scroll the window to the desired spot
nsIScrollableFrame* sf = nsLayoutUtils::FindScrollableFrameFor(aMetrics.GetScrollId());
bool scrollUpdated = false;
CSSPoint actualScrollOffset = ScrollFrameTo(sf, aMetrics.GetScrollOffset(), scrollUpdated);
if (scrollUpdated) {
// Correct the display port due to the difference between mScrollOffset and the
// actual scroll offset.
AdjustDisplayPortForScrollDelta(aMetrics, actualScrollOffset);
} else {
// For whatever reason we couldn't update the scroll offset on the scroll frame,
// which means the data APZ used for its displayport calculation is stale. Fall
// back to a sane default behaviour. Note that we don't tile-align the recentered
// displayport because tile-alignment depends on the scroll position, and the
// scroll position here is out of our control. See bug 966507 comment 21 for a
// more detailed explanation.
RecenterDisplayPort(aMetrics);
}
aMetrics.SetScrollOffset(actualScrollOffset);
// The pres shell resolution is updated by the the async zoom since the
// last paint.
float presShellResolution = aMetrics.GetPresShellResolution()
* aMetrics.GetAsyncZoom().scale;
aUtils->SetResolutionAndScaleTo(presShellResolution, presShellResolution);
// Finally, we set the displayport.
nsCOMPtr<nsIContent> content = nsLayoutUtils::FindContentFor(aMetrics.GetScrollId());
if (!content) {
return;
}
nsCOMPtr<nsIDOMElement> element = do_QueryInterface(content);
if (!element) {
return;
}
ScreenMargin margins = aMetrics.GetDisplayPortMargins();
aUtils->SetDisplayPortMarginsForElement(margins.left,
margins.top,
margins.right,
margins.bottom,
element, 0);
CSSRect baseCSS = aMetrics.CalculateCompositedRectInCssPixels();
nsRect base(0, 0,
baseCSS.width * nsPresContext::AppUnitsPerCSSPixel(),
baseCSS.height * nsPresContext::AppUnitsPerCSSPixel());
nsLayoutUtils::SetDisplayPortBaseIfNotSet(content, base);
}