gecko-dev/layout/base/nsDisplayList.cpp

787 lines
26 KiB
C++

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
* ***** BEGIN LICENSE BLOCK *****
* Version: MPL 1.1/GPL 2.0/LGPL 2.1
*
* The contents of this file are subject to the Mozilla Public License Version
* 1.1 (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
* http://www.mozilla.org/MPL/
*
* Software distributed under the License is distributed on an "AS IS" basis,
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
* for the specific language governing rights and limitations under the
* License.
*
* The Original Code is Novell code.
*
* The Initial Developer of the Novell Code is Novell Corporation.
* Portions created by Novell are Copyright (C) 2005 Novell. All Rights Reserved.
*
* Contributor(s):
* robert@ocallahan.org
*
* Alternatively, the contents of this file may be used under the terms of
* either of the GNU General Public License Version 2 or later (the "GPL"),
* or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
* in which case the provisions of the GPL or the LGPL are applicable instead
* of those above. If you wish to allow use of your version of this file only
* under the terms of either the GPL or the LGPL, and not to allow others to
* use your version of this file under the terms of the MPL, indicate your
* decision by deleting the provisions above and replace them with the notice
* and other provisions required by the GPL or the LGPL. If you do not delete
* the provisions above, a recipient may use your version of this file under
* the terms of any one of the MPL, the GPL or the LGPL.
*
* ***** END LICENSE BLOCK *****
*/
#include "nsDisplayList.h"
#include "nsCSSRendering.h"
#include "nsISelectionController.h"
#include "nsIPresShell.h"
#include "nsRegion.h"
#include "nsIViewManager.h"
#include "nsIBlender.h"
#include "nsTransform2D.h"
#ifdef MOZ_CAIRO_GFX
#include "gfxContext.h"
#endif
nsDisplayListBuilder::nsDisplayListBuilder(nsIFrame* aReferenceFrame,
PRBool aIsForEvents, nsIFrame* aMovingFrame)
: mReferenceFrame(aReferenceFrame),
mMovingFrame(aMovingFrame),
mIgnoreScrollFrame(nsnull),
mEventDelivery(aIsForEvents),
mIsAtRootOfPseudoStackingContext(PR_FALSE) {
PL_InitArenaPool(&mPool, "displayListArena", 1024, sizeof(void*)-1);
nsPresContext* pc = aReferenceFrame->GetPresContext();
nsIPresShell *shell = pc->PresShell();
PRBool suppressed;
shell->IsPaintingSuppressed(&suppressed);
mIsBackgroundOnly = suppressed;
if (pc->IsRenderingOnlySelection()) {
nsCOMPtr<nsISelectionController> selcon(do_QueryInterface(shell));
if (selcon) {
selcon->GetSelection(nsISelectionController::SELECTION_NORMAL,
getter_AddRefs(mBoundingSelection));
}
}
}
nsDisplayListBuilder::~nsDisplayListBuilder() {
PL_FreeArenaPool(&mPool);
PL_FinishArenaPool(&mPool);
}
void*
nsDisplayListBuilder::Allocate(size_t aSize) {
void *tmp;
PL_ARENA_ALLOCATE(tmp, &mPool, aSize);
return tmp;
}
void nsDisplayListSet::MoveTo(const nsDisplayListSet& aDestination) const
{
aDestination.BorderBackground()->AppendToTop(BorderBackground());
aDestination.BlockBorderBackgrounds()->AppendToTop(BlockBorderBackgrounds());
aDestination.Floats()->AppendToTop(Floats());
aDestination.Content()->AppendToTop(Content());
aDestination.PositionedDescendants()->AppendToTop(PositionedDescendants());
aDestination.Outlines()->AppendToTop(Outlines());
}
// Suitable for leaf items only, overridden by nsDisplayWrapList
PRBool
nsDisplayItem::OptimizeVisibility(nsDisplayListBuilder* aBuilder,
nsRegion* aVisibleRegion) {
nsRect bounds = GetBounds(aBuilder);
if (!aVisibleRegion->Intersects(bounds))
return PR_FALSE;
nsIFrame* f = GetUnderlyingFrame();
NS_ASSERTION(f, "GetUnderlyingFrame() must return non-null for leaf items");
if (aBuilder->HasMovingFrames() && aBuilder->IsMovingFrame(f)) {
// If this frame is in the moving subtree, and it doesn't
// require repainting just because it's moved, then just remove it now
// because it's not relevant.
if (!IsVaryingRelativeToFrame(aBuilder, aBuilder->GetRootMovingFrame()))
return PR_FALSE;
// keep it, but don't let it cover other display items (see nsLayoutUtils::
// ComputeRepaintRegionForCopy)
return PR_TRUE;
}
if (IsOpaque(aBuilder)) {
aVisibleRegion->SimpleSubtract(bounds);
}
return PR_TRUE;
}
void
nsDisplayList::FlattenTo(nsVoidArray* aElements) {
nsDisplayItem* item;
while ((item = RemoveBottom()) != nsnull) {
if (item->GetType() == nsDisplayItem::TYPE_WRAPLIST) {
item->GetList()->FlattenTo(aElements);
item->~nsDisplayItem();
} else {
aElements->AppendElement(item);
}
}
}
void
nsDisplayList::OptimizeVisibility(nsDisplayListBuilder* aBuilder,
nsRegion* aVisibleRegion) {
nsVoidArray elements;
FlattenTo(&elements);
for (PRInt32 i = elements.Count() - 1; i >= 0; --i) {
nsDisplayItem* item = NS_STATIC_CAST(nsDisplayItem*, elements.ElementAt(i));
nsDisplayItem* belowItem = i < 1 ? nsnull :
NS_STATIC_CAST(nsDisplayItem*, elements.ElementAt(i - 1));
if (belowItem && item->TryMerge(aBuilder, belowItem)) {
belowItem->~nsDisplayItem();
elements.ReplaceElementAt(item, i - 1);
continue;
}
if (item->OptimizeVisibility(aBuilder, aVisibleRegion)) {
AppendToBottom(item);
} else {
item->~nsDisplayItem();
}
}
}
void nsDisplayList::Paint(nsDisplayListBuilder* aBuilder, nsIRenderingContext* aCtx,
const nsRect& aDirtyRect) const {
for (nsDisplayItem* i = GetBottom(); i != nsnull; i = i->GetAbove()) {
i->Paint(aBuilder, aCtx, aDirtyRect);
}
}
PRUint32 nsDisplayList::Count() const {
PRUint32 count = 0;
for (nsDisplayItem* i = GetBottom(); i; i = i->GetAbove()) {
++count;
}
return count;
}
nsDisplayItem* nsDisplayList::RemoveBottom() {
nsDisplayItem* item = mSentinel.mAbove;
if (!item)
return nsnull;
mSentinel.mAbove = item->mAbove;
if (item == mTop) {
// must have been the only item
mTop = &mSentinel;
}
item->mAbove = nsnull;
return item;
}
void nsDisplayList::DeleteBottom() {
nsDisplayItem* item = RemoveBottom();
if (item) {
item->~nsDisplayItem();
}
}
void nsDisplayList::DeleteAll() {
nsDisplayItem* item;
while ((item = RemoveBottom()) != nsnull) {
item->~nsDisplayItem();
}
}
nsIFrame* nsDisplayList::HitTest(nsDisplayListBuilder* aBuilder, nsPoint aPt) const {
nsVoidArray elements;
nsDisplayItem* item;
for (item = GetBottom(); item; item = item->GetAbove()) {
elements.AppendElement(item);
}
for (PRInt32 i = elements.Count() - 1; i >= 0; --i) {
item = NS_STATIC_CAST(nsDisplayItem*, elements.ElementAt(i));
if (item->GetBounds(aBuilder).Contains(aPt)) {
nsIFrame* f = item->HitTest(aBuilder, aPt);
// Handle the XUL 'mousethrough' feature.
if (f) {
PRBool mouseThrough = PR_FALSE;
f->GetMouseThrough(mouseThrough);
if (!mouseThrough)
return f;
}
}
}
return nsnull;
}
typedef PRBool (* SortLEQ)(nsDisplayItem* aItem1, nsDisplayItem* aItem2,
void* aClosure);
static void Sort(nsDisplayList* aList, PRInt32 aCount, SortLEQ aCmp, void* aClosure) {
if (aCount < 2)
return;
nsDisplayList list1;
nsDisplayList list2;
int i;
PRInt32 half = aCount/2;
PRBool sorted = PR_TRUE;
nsDisplayItem* prev = nsnull;
for (i = 0; i < aCount; ++i) {
nsDisplayItem* item = aList->RemoveBottom();
(i < half ? &list1 : &list2)->AppendToTop(item);
if (sorted && prev && !aCmp(prev, item, aClosure)) {
sorted = PR_FALSE;
}
prev = item;
}
if (sorted) {
aList->AppendToTop(&list1);
aList->AppendToTop(&list2);
return;
}
Sort(&list1, half, aCmp, aClosure);
Sort(&list2, aCount - half, aCmp, aClosure);
for (i = 0; i < aCount; ++i) {
if (list1.GetBottom() &&
(!list2.GetBottom() ||
aCmp(list1.GetBottom(), list2.GetBottom(), aClosure))) {
aList->AppendToTop(list1.RemoveBottom());
} else {
aList->AppendToTop(list2.RemoveBottom());
}
}
}
static PRBool IsContentLEQ(nsDisplayItem* aItem1, nsDisplayItem* aItem2,
void* aClosure) {
// These GetUnderlyingFrame calls return non-null because we're only used
// in sorting
return nsLayoutUtils::CompareTreePosition(
aItem1->GetUnderlyingFrame()->GetContent(),
aItem2->GetUnderlyingFrame()->GetContent(),
NS_STATIC_CAST(nsIContent*, aClosure)) <= 0;
}
static PRBool IsZOrderLEQ(nsDisplayItem* aItem1, nsDisplayItem* aItem2,
void* aClosure) {
// These GetUnderlyingFrame calls return non-null because we're only used
// in sorting
PRInt32 diff = nsLayoutUtils::GetZIndex(aItem1->GetUnderlyingFrame()) -
nsLayoutUtils::GetZIndex(aItem2->GetUnderlyingFrame());
if (diff == 0)
return IsContentLEQ(aItem1, aItem2, aClosure);
return diff < 0;
}
void nsDisplayList::ExplodeAnonymousChildLists(nsDisplayListBuilder* aBuilder) {
// See if there's anything to do
PRBool anyAnonymousItems = PR_FALSE;
nsDisplayItem* i;
for (i = GetBottom(); i != nsnull; i = i->GetAbove()) {
if (!i->GetUnderlyingFrame()) {
anyAnonymousItems = PR_TRUE;
break;
}
}
if (!anyAnonymousItems)
return;
nsDisplayList tmp;
while ((i = RemoveBottom()) != nsnull) {
if (i->GetUnderlyingFrame()) {
tmp.AppendToTop(i);
} else {
nsDisplayList* list = i->GetList();
NS_ASSERTION(list, "leaf items can't be anonymous");
list->ExplodeAnonymousChildLists(aBuilder);
nsDisplayItem* j;
while ((j = list->RemoveBottom()) != nsnull) {
tmp.AppendToTop(NS_STATIC_CAST(nsDisplayWrapList*, i)->
WrapWithClone(aBuilder, j));
}
i->~nsDisplayItem();
}
}
AppendToTop(&tmp);
}
void nsDisplayList::SortByZOrder(nsDisplayListBuilder* aBuilder,
nsIContent* aCommonAncestor) {
ExplodeAnonymousChildLists(aBuilder);
Sort(this, Count(), IsZOrderLEQ, aCommonAncestor);
}
void nsDisplayList::SortByContentOrder(nsDisplayListBuilder* aBuilder,
nsIContent* aCommonAncestor) {
ExplodeAnonymousChildLists(aBuilder);
Sort(this, Count(), IsContentLEQ, aCommonAncestor);
}
static PRBool
NonZeroStyleCoord(const nsStyleCoord& aCoord) {
switch (aCoord.GetUnit()) {
case eStyleUnit_Percent:
return aCoord.GetPercentValue() > 0;
case eStyleUnit_Coord:
return aCoord.GetCoordValue() > 0;
case eStyleUnit_Null:
return PR_FALSE;
default:
return PR_TRUE;
}
}
static PRBool
HasNonZeroBorderRadius(const nsStyleBorder* aBorder) {
nsStyleCoord coord;
aBorder->mBorderRadius.GetTop(coord);
if (NonZeroStyleCoord(coord)) return PR_TRUE;
aBorder->mBorderRadius.GetRight(coord);
if (NonZeroStyleCoord(coord)) return PR_TRUE;
aBorder->mBorderRadius.GetBottom(coord);
if (NonZeroStyleCoord(coord)) return PR_TRUE;
aBorder->mBorderRadius.GetLeft(coord);
if (NonZeroStyleCoord(coord)) return PR_TRUE;
return PR_FALSE;
}
PRBool
nsDisplayBackground::IsOpaque(nsDisplayListBuilder* aBuilder) {
// theme background overrides any other background
if (mFrame->IsThemed())
return PR_FALSE;
PRBool isCanvas;
const nsStyleBackground* bg;
PRBool hasBG =
nsCSSRendering::FindBackground(mFrame->GetPresContext(), mFrame, &bg, &isCanvas);
if (!hasBG || (bg->mBackgroundFlags & NS_STYLE_BG_COLOR_TRANSPARENT) ||
bg->mBackgroundClip != NS_STYLE_BG_CLIP_BORDER ||
HasNonZeroBorderRadius(mFrame->GetStyleBorder()) ||
NS_GET_A(bg->mBackgroundColor) < 255)
return PR_FALSE;
return PR_TRUE;
}
PRBool
nsDisplayBackground::IsUniform(nsDisplayListBuilder* aBuilder) {
// theme background overrides any other background
if (mFrame->IsThemed())
return PR_FALSE;
PRBool isCanvas;
const nsStyleBackground* bg;
PRBool hasBG =
nsCSSRendering::FindBackground(mFrame->GetPresContext(), mFrame, &bg, &isCanvas);
if (!hasBG)
return PR_TRUE;
if ((bg->mBackgroundFlags & NS_STYLE_BG_IMAGE_NONE) &&
!HasNonZeroBorderRadius(mFrame->GetStyleBorder()) &&
bg->mBackgroundClip == NS_STYLE_BG_CLIP_BORDER)
return PR_TRUE;
return PR_FALSE;
}
PRBool
nsDisplayBackground::IsVaryingRelativeToFrame(nsDisplayListBuilder* aBuilder,
nsIFrame* aAncestorFrame)
{
PRBool isCanvas;
const nsStyleBackground* bg;
PRBool hasBG =
nsCSSRendering::FindBackground(mFrame->GetPresContext(), mFrame, &bg, &isCanvas);
if (!hasBG)
return PR_FALSE;
if (!bg->HasFixedBackground())
return PR_FALSE;
// aAncestorFrame is an ancestor of this frame ... if it's in our document
// then we'll be moving relative to the viewport, so we will change our
// display. If it's in some ancestor document then we won't be moving
// relative to the viewport so we won't change our display.
for (nsIFrame* f = mFrame->GetParent(); f; f = f->GetParent()) {
if (f == aAncestorFrame)
return PR_TRUE;
}
return PR_FALSE;
}
void
nsDisplayBackground::Paint(nsDisplayListBuilder* aBuilder,
nsIRenderingContext* aCtx, const nsRect& aDirtyRect) {
nsPoint offset = aBuilder->ToReferenceFrame(mFrame);
nsCSSRendering::PaintBackground(mFrame->GetPresContext(), *aCtx, mFrame,
aDirtyRect, nsRect(offset, mFrame->GetSize()),
*mFrame->GetStyleBorder(),
*mFrame->GetStylePadding(),
mFrame->HonorPrintBackgroundSettings());
}
nsRect
nsDisplayOutline::GetBounds(nsDisplayListBuilder* aBuilder) {
return mFrame->GetOverflowRect() + aBuilder->ToReferenceFrame(mFrame);
}
void
nsDisplayOutline::Paint(nsDisplayListBuilder* aBuilder,
nsIRenderingContext* aCtx, const nsRect& aDirtyRect) {
// TODO join outlines together
nsPoint offset = aBuilder->ToReferenceFrame(mFrame);
nsCSSRendering::PaintOutline(mFrame->GetPresContext(), *aCtx, mFrame,
aDirtyRect, nsRect(offset, mFrame->GetSize()),
*mFrame->GetStyleBorder(),
*mFrame->GetStyleOutline(),
mFrame->GetStyleContext(), 0);
}
void
nsDisplayBorder::Paint(nsDisplayListBuilder* aBuilder,
nsIRenderingContext* aCtx, const nsRect& aDirtyRect) {
nsPoint offset = aBuilder->ToReferenceFrame(mFrame);
nsCSSRendering::PaintBorder(mFrame->GetPresContext(), *aCtx, mFrame,
aDirtyRect, nsRect(offset, mFrame->GetSize()),
*mFrame->GetStyleBorder(),
mFrame->GetStyleContext(), mFrame->GetSkipSides());
}
nsDisplayWrapList::nsDisplayWrapList(nsIFrame* aFrame, nsDisplayList* aList)
: mFrame(aFrame) {
mList.AppendToTop(aList);
}
nsDisplayWrapList::nsDisplayWrapList(nsIFrame* aFrame, nsDisplayItem* aItem)
: mFrame(aFrame) {
mList.AppendToTop(aItem);
}
nsDisplayWrapList::~nsDisplayWrapList() {
mList.DeleteAll();
}
nsIFrame*
nsDisplayWrapList::HitTest(nsDisplayListBuilder* aBuilder, nsPoint aPt) {
return mList.HitTest(aBuilder, aPt);
}
nsRect
nsDisplayWrapList::GetBounds(nsDisplayListBuilder* aBuilder) {
nsRect bounds;
for (nsDisplayItem* i = mList.GetBottom(); i != nsnull; i = i->GetAbove()) {
bounds.UnionRect(bounds, i->GetBounds(aBuilder));
}
return bounds;
}
PRBool
nsDisplayWrapList::OptimizeVisibility(nsDisplayListBuilder* aBuilder,
nsRegion* aVisibleRegion) {
mList.OptimizeVisibility(aBuilder, aVisibleRegion);
// If none of the items are visible, they will all have been deleted
return mList.GetTop() != nsnull;
}
PRBool
nsDisplayWrapList::IsOpaque(nsDisplayListBuilder* aBuilder) {
// We could try to do something but let's conservatively just return PR_FALSE.
// We reimplement OptimizeVisibility and that's what really matters
return PR_FALSE;
}
PRBool nsDisplayWrapList::IsUniform(nsDisplayListBuilder* aBuilder) {
// We could try to do something but let's conservatively just return PR_FALSE.
return PR_FALSE;
}
PRBool nsDisplayWrapList::IsVaryingRelativeToFrame(nsDisplayListBuilder* aBuilder,
nsIFrame* aFrame) {
for (nsDisplayItem* i = mList.GetBottom(); i != nsnull; i = i->GetAbove()) {
if (i->IsVaryingRelativeToFrame(aBuilder, aFrame))
return PR_TRUE;
}
return PR_FALSE;
}
void nsDisplayWrapList::Paint(nsDisplayListBuilder* aBuilder,
nsIRenderingContext* aCtx, const nsRect& aDirtyRect) {
mList.Paint(aBuilder, aCtx, aDirtyRect);
}
static nsresult
WrapDisplayList(nsDisplayListBuilder* aBuilder, nsIFrame* aFrame,
nsDisplayList* aList, nsDisplayWrapper* aWrapper) {
if (!aList->GetTop())
return NS_OK;
nsDisplayItem* item = aWrapper->WrapList(aBuilder, aFrame, aList);
if (!item)
return NS_ERROR_OUT_OF_MEMORY;
// aList was emptied
aList->AppendToTop(item);
return NS_OK;
}
static nsresult
WrapEachDisplayItem(nsDisplayListBuilder* aBuilder,
nsDisplayList* aList, nsDisplayWrapper* aWrapper) {
nsDisplayList newList;
nsDisplayItem* item;
while ((item = aList->RemoveBottom())) {
item = aWrapper->WrapItem(aBuilder, item);
if (!item)
return NS_ERROR_OUT_OF_MEMORY;
newList.AppendToTop(item);
}
// aList was emptied
aList->AppendToTop(&newList);
return NS_OK;
}
nsresult nsDisplayWrapper::WrapLists(nsDisplayListBuilder* aBuilder,
nsIFrame* aFrame, const nsDisplayListSet& aIn, const nsDisplayListSet& aOut)
{
nsresult rv = WrapListsInPlace(aBuilder, aFrame, aIn);
NS_ENSURE_SUCCESS(rv, rv);
if (&aOut == &aIn)
return NS_OK;
aOut.BorderBackground()->AppendToTop(aIn.BorderBackground());
aOut.BlockBorderBackgrounds()->AppendToTop(aIn.BlockBorderBackgrounds());
aOut.Floats()->AppendToTop(aIn.Floats());
aOut.Content()->AppendToTop(aIn.Content());
aOut.PositionedDescendants()->AppendToTop(aIn.PositionedDescendants());
aOut.Outlines()->AppendToTop(aIn.Outlines());
return NS_OK;
}
nsresult nsDisplayWrapper::WrapListsInPlace(nsDisplayListBuilder* aBuilder,
nsIFrame* aFrame, const nsDisplayListSet& aLists)
{
nsresult rv;
if (WrapBorderBackground()) {
// Our border-backgrounds are in-flow
rv = WrapDisplayList(aBuilder, aFrame, aLists.BorderBackground(), this);
NS_ENSURE_SUCCESS(rv, rv);
}
// Our block border-backgrounds are in-flow
rv = WrapDisplayList(aBuilder, aFrame, aLists.BlockBorderBackgrounds(), this);
NS_ENSURE_SUCCESS(rv, rv);
// The floats are not in flow
rv = WrapEachDisplayItem(aBuilder, aLists.Floats(), this);
NS_ENSURE_SUCCESS(rv, rv);
// Our child content is in flow
rv = WrapDisplayList(aBuilder, aFrame, aLists.Content(), this);
NS_ENSURE_SUCCESS(rv, rv);
// The positioned descendants may not be in-flow
rv = WrapEachDisplayItem(aBuilder, aLists.PositionedDescendants(), this);
NS_ENSURE_SUCCESS(rv, rv);
// The outlines may not be in-flow
return WrapEachDisplayItem(aBuilder, aLists.Outlines(), this);
}
MOZ_DECL_CTOR_COUNTER(nsDisplayOpacity)
nsDisplayOpacity::nsDisplayOpacity(nsIFrame* aFrame, nsDisplayList* aList)
: nsDisplayWrapList(aFrame, aList), mNeedAlpha(PR_TRUE) {
MOZ_COUNT_CTOR(nsDisplayOpacity);
}
#ifdef NS_BUILD_REFCNT_LOGGING
nsDisplayOpacity::~nsDisplayOpacity() {
MOZ_COUNT_DTOR(nsDisplayOpacity);
}
#endif
PRBool nsDisplayOpacity::IsOpaque(nsDisplayListBuilder* aBuilder) {
// We are never opaque, if our opacity was < 1 then we wouldn't have
// been created.
return PR_FALSE;
}
void nsDisplayOpacity::Paint(nsDisplayListBuilder* aBuilder,
nsIRenderingContext* aCtx, const nsRect& aDirtyRect)
{
// XXX This way of handling 'opacity' creates exponential time blowup in the
// depth of nested translucent elements. This will be fixed when we move to
// cairo with support for real alpha channels in surfaces, so we don't have
// to do this white/black hack anymore.
nsIViewManager* vm = mFrame->GetPresContext()->GetViewManager();
float opacity = mFrame->GetStyleDisplay()->mOpacity;
nsRect bounds;
bounds.IntersectRect(GetBounds(aBuilder), aDirtyRect);
#ifdef MOZ_CAIRO_GFX
nsCOMPtr<nsIDeviceContext> devCtx;
aCtx->GetDeviceContext(*getter_AddRefs(devCtx));
float t2p = devCtx->AppUnitsToDevUnits();
nsRefPtr<gfxContext> ctx = (gfxContext*)aCtx->GetNativeGraphicData(nsIRenderingContext::NATIVE_THEBES_CONTEXT);
ctx->Save();
ctx->NewPath();
ctx->Rectangle(gfxRect(bounds.x * t2p,
bounds.y * t2p,
bounds.width * t2p,
bounds.height * t2p),
PR_TRUE);
ctx->Clip();
if (mNeedAlpha)
ctx->PushGroup(gfxContext::CONTENT_COLOR_ALPHA);
else
ctx->PushGroup(gfxContext::CONTENT_COLOR);
nsDisplayWrapList::Paint(aBuilder, aCtx, bounds);
ctx->PopGroupToSource();
ctx->SetOperator(gfxContext::OPERATOR_OVER);
ctx->Paint(opacity);
ctx->Restore();
#elif !defined(XP_MACOSX)
nsIViewManager::BlendingBuffers* buffers =
vm->CreateBlendingBuffers(aCtx, PR_FALSE, nsnull, mNeedAlpha, bounds);
if (!buffers) {
NS_WARNING("Could not create blending buffers for translucent painting; ignoring opacity");
nsDisplayWrapList::Paint(aBuilder, aCtx, aDirtyRect);
return;
}
// Paint onto black, and also onto white if necessary
nsDisplayWrapList::Paint(aBuilder, buffers->mBlackCX, bounds);
if (buffers->mWhiteCX) {
nsDisplayWrapList::Paint(aBuilder, buffers->mWhiteCX, bounds);
}
nsTransform2D* transform;
nsresult rv = aCtx->GetCurrentTransform(transform);
if (NS_FAILED(rv))
return;
nsRect damageRectInPixels = bounds;
transform->TransformCoord(&damageRectInPixels.x, &damageRectInPixels.y,
&damageRectInPixels.width, &damageRectInPixels.height);
// If blender creation failed then we would have not received a buffers object
nsIBlender* blender = vm->GetBlender();
blender->Blend(0, 0, damageRectInPixels.width, damageRectInPixels.height,
buffers->mBlackCX, aCtx,
damageRectInPixels.x, damageRectInPixels.y,
opacity, buffers->mWhiteCX,
NS_RGB(0, 0, 0), NS_RGB(255, 255, 255));
delete buffers;
#else
// bug 325296 workaround
nsDisplayWrapList::Paint(aBuilder, aCtx, aDirtyRect);
#endif /* MOZ_CAIRO_GFX */
}
PRBool nsDisplayOpacity::OptimizeVisibility(nsDisplayListBuilder* aBuilder,
nsRegion* aVisibleRegion) {
// Our children are translucent so we should not allow them to subtract
// area from aVisibleRegion. We do need to find out what is visible under
// our children in the temporary compositing buffer, because if our children
// paint our entire bounds opaquely then we don't need an alpha channel in
// the temporary compositing buffer.
nsRegion visibleUnderChildren = *aVisibleRegion;
PRBool anyVisibleChildren =
nsDisplayWrapList::OptimizeVisibility(aBuilder, &visibleUnderChildren);
if (!anyVisibleChildren)
return PR_FALSE;
mNeedAlpha = visibleUnderChildren.Intersects(GetBounds(aBuilder));
return PR_TRUE;
}
PRBool nsDisplayOpacity::TryMerge(nsDisplayListBuilder* aBuilder, nsDisplayItem* aItem) {
if (aItem->GetType() != TYPE_OPACITY)
return PR_FALSE;
// items for the same content element should be merged into a single
// compositing group
// aItem->GetUnderlyingFrame() returns non-null because it's nsDisplayOpacity
if (aItem->GetUnderlyingFrame()->GetContent() != mFrame->GetContent())
return PR_FALSE;
mList.AppendToBottom(&NS_STATIC_CAST(nsDisplayOpacity*, aItem)->mList);
return PR_TRUE;
}
MOZ_DECL_CTOR_COUNTER(nsDisplayClip)
nsDisplayClip::nsDisplayClip(nsIFrame* aFrame, nsDisplayItem* aItem,
const nsRect& aRect)
: nsDisplayWrapList(aFrame, aItem), mClip(aRect) {
MOZ_COUNT_CTOR(nsDisplayClip);
}
nsDisplayClip::nsDisplayClip(nsIFrame* aFrame, nsDisplayList* aList,
const nsRect& aRect)
: nsDisplayWrapList(aFrame, aList), mClip(aRect) {
MOZ_COUNT_CTOR(nsDisplayClip);
}
nsRect nsDisplayClip::GetBounds(nsDisplayListBuilder* aBuilder) {
nsRect r = nsDisplayWrapList::GetBounds(aBuilder);
r.IntersectRect(mClip, r);
return r;
}
#ifdef NS_BUILD_REFCNT_LOGGING
nsDisplayClip::~nsDisplayClip() {
MOZ_COUNT_DTOR(nsDisplayClip);
}
#endif
void nsDisplayClip::Paint(nsDisplayListBuilder* aBuilder,
nsIRenderingContext* aCtx, const nsRect& aDirtyRect) {
nsRect dirty;
dirty.IntersectRect(mClip, aDirtyRect);
aCtx->PushState();
aCtx->SetClipRect(dirty, nsClipCombine_kIntersect);
nsDisplayWrapList::Paint(aBuilder, aCtx, dirty);
aCtx->PopState();
}
PRBool nsDisplayClip::OptimizeVisibility(nsDisplayListBuilder* aBuilder,
nsRegion* aVisibleRegion) {
nsRegion clipped;
clipped.And(*aVisibleRegion, mClip);
nsRegion rNew(clipped);
PRBool anyVisible = nsDisplayWrapList::OptimizeVisibility(aBuilder, &rNew);
nsRegion subtracted;
subtracted.Sub(clipped, rNew);
aVisibleRegion->SimpleSubtract(subtracted);
return anyVisible;
}
PRBool nsDisplayClip::TryMerge(nsDisplayListBuilder* aBuilder,
nsDisplayItem* aItem) {
if (aItem->GetType() != TYPE_CLIP)
return PR_FALSE;
nsDisplayClip* other = NS_STATIC_CAST(nsDisplayClip*, aItem);
if (other->mClip != mClip)
return PR_FALSE;
mList.AppendToBottom(&other->mList);
return PR_TRUE;
}
nsDisplayWrapList* nsDisplayClip::WrapWithClone(nsDisplayListBuilder* aBuilder,
nsDisplayItem* aItem) {
return new (aBuilder) nsDisplayClip(aItem->GetUnderlyingFrame(), aItem, mClip);
}