Bug 1127066 - Factor out code common to APZCCallbackHelper::UpdateRootFrame and UpdateSubFrame. r=kats

--HG--
extra : source : fe1ea639cdfde510a2bb51d2f113fb14809b6b43
This commit is contained in:
Botond Ballo 2015-01-23 18:54:19 -05:00
Родитель 9b07a3a0af
Коммит 54b4a664cb
1 изменённых файлов: 94 добавлений и 100 удалений

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@ -106,121 +106,115 @@ ScrollFrameTo(nsIScrollableFrame* aFrame, const CSSPoint& aPoint, bool& aSuccess
return geckoScrollPosition;
}
/**
* Scroll the scroll frame associated with |aContent| to the scroll position
* requested in |aMetrics|.
* The scroll offset in |aMetrics| is updated to reflect the actual scroll
* position.
* The displayport stored in |aMetrics| is updated to reflect any difference
* between the requested and actual scroll positions.
*/
static void
ScrollFrame(nsIContent* aContent,
FrameMetrics& aMetrics)
{
// 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);
}
static void
SetDisplayPortMargins(nsIDOMWindowUtils* aUtils,
nsIContent* aContent,
FrameMetrics& aMetrics)
{
if (!aContent) {
return;
}
nsCOMPtr<nsIDOMElement> element = do_QueryInterface(aContent);
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(aContent, base);
}
void
APZCCallbackHelper::UpdateRootFrame(nsIDOMWindowUtils* aUtils,
FrameMetrics& aMetrics)
{
// Precondition checks
MOZ_ASSERT(aUtils);
MOZ_ASSERT(aMetrics.GetUseDisplayPortMargins());
if (aMetrics.GetScrollId() == FrameMetrics::NULL_SCROLL_ID) {
return;
}
// 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);
// 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);
// Scroll the window to the desired spot
nsIScrollableFrame* sf = nsLayoutUtils::FindScrollableFrameFor(aMetrics.GetScrollId());
bool scrollUpdated = false;
CSSPoint actualScrollOffset = ScrollFrameTo(sf, aMetrics.GetScrollOffset(), scrollUpdated);
nsIContent* content = nsLayoutUtils::FindContentFor(aMetrics.GetScrollId());
ScrollFrame(content, aMetrics);
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);
}
// 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);
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);
SetDisplayPortMargins(aUtils, content, aMetrics);
}
void
APZCCallbackHelper::UpdateSubFrame(nsIContent* aContent,
FrameMetrics& aMetrics)
{
// Precondition checks
MOZ_ASSERT(aContent);
MOZ_ASSERT(aMetrics.GetUseDisplayPortMargins());
if (aMetrics.GetScrollId() == FrameMetrics::NULL_SCROLL_ID) {
return;
}
// Precondition checks
MOZ_ASSERT(aContent);
MOZ_ASSERT(aMetrics.GetUseDisplayPortMargins());
nsCOMPtr<nsIDOMWindowUtils> utils = GetDOMWindowUtils(aContent);
if (!utils) {
return;
}
// We currently do not support zooming arbitrary subframes. They can only
// be scrolled, so here we only have to set the scroll position and displayport.
nsIScrollableFrame* sf = nsLayoutUtils::FindScrollableFrameFor(aMetrics.GetScrollId());
bool scrollUpdated = false;
CSSPoint actualScrollOffset = ScrollFrameTo(sf, aMetrics.GetScrollOffset(), scrollUpdated);
nsCOMPtr<nsIDOMElement> element = do_QueryInterface(aContent);
if (element) {
if (scrollUpdated) {
AdjustDisplayPortForScrollDelta(aMetrics, actualScrollOffset);
} else {
RecenterDisplayPort(aMetrics);
}
ScreenMargin margins = aMetrics.GetDisplayPortMargins();
utils->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(aContent, base);
}
aMetrics.SetScrollOffset(actualScrollOffset);
// We don't currently support zooming for subframes, so nothing extra
// needs to be done beyond the tasks common to this and UpdateRootFrame.
ScrollFrame(aContent, aMetrics);
if (nsCOMPtr<nsIDOMWindowUtils> utils = GetDOMWindowUtils(aContent)) {
SetDisplayPortMargins(utils, aContent, aMetrics);
}
}
already_AddRefed<nsIDOMWindowUtils>