gecko/layout/generic/nsHTMLCanvasFrame.cpp
Robert O'Callahan 6b9e0b532c Bug 1022612. Part 27: Make FrameLayerBuilder responsible for setting all layer visible regions. r=mattwoodrow
Calling Layer::SetVisibleRegion multiple times in a transaction can result in
unnecessary IPC traffic.

This patch removes Intersect(childGfxBounds). This is only needed to
restrict the visible region to something sane for 3D transforms, and this will
be fixed up in a later patch.

--HG--
extra : rebase_source : 4518bc060fa2c28dacdb7d3aaeca55a148dfe762
2014-06-18 15:12:55 +12:00

344 lines
11 KiB
C++

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
/* rendering object for the HTML <canvas> element */
#include "nsHTMLCanvasFrame.h"
#include "nsGkAtoms.h"
#include "mozilla/dom/HTMLCanvasElement.h"
#include "nsDisplayList.h"
#include "nsLayoutUtils.h"
#include "Layers.h"
#include "ActiveLayerTracker.h"
#include <algorithm>
using namespace mozilla;
using namespace mozilla::dom;
using namespace mozilla::layers;
class nsDisplayCanvas : public nsDisplayItem {
public:
nsDisplayCanvas(nsDisplayListBuilder* aBuilder, nsIFrame* aFrame)
: nsDisplayItem(aBuilder, aFrame)
{
MOZ_COUNT_CTOR(nsDisplayCanvas);
}
#ifdef NS_BUILD_REFCNT_LOGGING
virtual ~nsDisplayCanvas() {
MOZ_COUNT_DTOR(nsDisplayCanvas);
}
#endif
NS_DISPLAY_DECL_NAME("nsDisplayCanvas", TYPE_CANVAS)
virtual nsRegion GetOpaqueRegion(nsDisplayListBuilder* aBuilder,
bool* aSnap) MOZ_OVERRIDE {
*aSnap = false;
nsIFrame* f = Frame();
HTMLCanvasElement *canvas =
HTMLCanvasElement::FromContent(f->GetContent());
nsRegion result;
if (canvas->GetIsOpaque()) {
result = GetBounds(aBuilder, aSnap);
}
return result;
}
virtual nsRect GetBounds(nsDisplayListBuilder* aBuilder,
bool* aSnap) MOZ_OVERRIDE {
*aSnap = true;
nsHTMLCanvasFrame* f = static_cast<nsHTMLCanvasFrame*>(Frame());
return f->GetInnerArea() + ToReferenceFrame();
}
virtual already_AddRefed<Layer> BuildLayer(nsDisplayListBuilder* aBuilder,
LayerManager* aManager,
const ContainerLayerParameters& aContainerParameters) MOZ_OVERRIDE
{
return static_cast<nsHTMLCanvasFrame*>(mFrame)->
BuildLayer(aBuilder, aManager, this, aContainerParameters);
}
virtual LayerState GetLayerState(nsDisplayListBuilder* aBuilder,
LayerManager* aManager,
const ContainerLayerParameters& aParameters) MOZ_OVERRIDE
{
if (HTMLCanvasElement::FromContent(mFrame->GetContent())->ShouldForceInactiveLayer(aManager))
return LAYER_INACTIVE;
// If compositing is cheap, just do that
if (aManager->IsCompositingCheap() ||
ActiveLayerTracker::IsContentActive(mFrame))
return mozilla::LAYER_ACTIVE;
return LAYER_INACTIVE;
}
};
nsIFrame*
NS_NewHTMLCanvasFrame(nsIPresShell* aPresShell, nsStyleContext* aContext)
{
return new (aPresShell) nsHTMLCanvasFrame(aContext);
}
NS_QUERYFRAME_HEAD(nsHTMLCanvasFrame)
NS_QUERYFRAME_ENTRY(nsHTMLCanvasFrame)
NS_QUERYFRAME_TAIL_INHERITING(nsContainerFrame)
NS_IMPL_FRAMEARENA_HELPERS(nsHTMLCanvasFrame)
void
nsHTMLCanvasFrame::Init(nsIContent* aContent,
nsContainerFrame* aParent,
nsIFrame* aPrevInFlow)
{
nsContainerFrame::Init(aContent, aParent, aPrevInFlow);
// We can fill in the canvas before the canvas frame is created, in
// which case we never get around to marking the content as active. Therefore,
// we mark it active here when we create the frame.
ActiveLayerTracker::NotifyContentChange(this);
}
nsHTMLCanvasFrame::~nsHTMLCanvasFrame()
{
}
nsIntSize
nsHTMLCanvasFrame::GetCanvasSize()
{
nsIntSize size(0,0);
HTMLCanvasElement *canvas =
HTMLCanvasElement::FromContentOrNull(GetContent());
if (canvas) {
size = canvas->GetSize();
} else {
NS_NOTREACHED("couldn't get canvas size");
}
return size;
}
/* virtual */ nscoord
nsHTMLCanvasFrame::GetMinWidth(nsRenderingContext *aRenderingContext)
{
// XXX The caller doesn't account for constraints of the height,
// min-height, and max-height properties.
nscoord result = nsPresContext::CSSPixelsToAppUnits(GetCanvasSize().width);
DISPLAY_MIN_WIDTH(this, result);
return result;
}
/* virtual */ nscoord
nsHTMLCanvasFrame::GetPrefWidth(nsRenderingContext *aRenderingContext)
{
// XXX The caller doesn't account for constraints of the height,
// min-height, and max-height properties.
nscoord result = nsPresContext::CSSPixelsToAppUnits(GetCanvasSize().width);
DISPLAY_PREF_WIDTH(this, result);
return result;
}
/* virtual */ nsSize
nsHTMLCanvasFrame::GetIntrinsicRatio()
{
nsIntSize size(GetCanvasSize());
return nsSize(nsPresContext::CSSPixelsToAppUnits(size.width),
nsPresContext::CSSPixelsToAppUnits(size.height));
}
/* virtual */ nsSize
nsHTMLCanvasFrame::ComputeSize(nsRenderingContext *aRenderingContext,
nsSize aCBSize, nscoord aAvailableWidth,
nsSize aMargin, nsSize aBorder, nsSize aPadding,
uint32_t aFlags)
{
nsIntSize size = GetCanvasSize();
IntrinsicSize intrinsicSize;
intrinsicSize.width.SetCoordValue(nsPresContext::CSSPixelsToAppUnits(size.width));
intrinsicSize.height.SetCoordValue(nsPresContext::CSSPixelsToAppUnits(size.height));
nsSize intrinsicRatio = GetIntrinsicRatio(); // won't actually be used
return nsLayoutUtils::ComputeSizeWithIntrinsicDimensions(
aRenderingContext, this,
intrinsicSize, intrinsicRatio, aCBSize,
aMargin, aBorder, aPadding);
}
void
nsHTMLCanvasFrame::Reflow(nsPresContext* aPresContext,
nsHTMLReflowMetrics& aMetrics,
const nsHTMLReflowState& aReflowState,
nsReflowStatus& aStatus)
{
DO_GLOBAL_REFLOW_COUNT("nsHTMLCanvasFrame");
DISPLAY_REFLOW(aPresContext, this, aReflowState, aMetrics, aStatus);
NS_FRAME_TRACE(NS_FRAME_TRACE_CALLS,
("enter nsHTMLCanvasFrame::Reflow: availSize=%d,%d",
aReflowState.AvailableWidth(), aReflowState.AvailableHeight()));
NS_PRECONDITION(mState & NS_FRAME_IN_REFLOW, "frame is not in reflow");
aStatus = NS_FRAME_COMPLETE;
aMetrics.Width() = aReflowState.ComputedWidth();
aMetrics.Height() = aReflowState.ComputedHeight();
// stash this away so we can compute our inner area later
mBorderPadding = aReflowState.ComputedPhysicalBorderPadding();
aMetrics.Width() += mBorderPadding.left + mBorderPadding.right;
aMetrics.Height() += mBorderPadding.top + mBorderPadding.bottom;
if (GetPrevInFlow()) {
nscoord y = GetContinuationOffset(&aMetrics.Width());
aMetrics.Height() -= y + mBorderPadding.top;
aMetrics.Height() = std::max(0, aMetrics.Height());
}
aMetrics.SetOverflowAreasToDesiredBounds();
FinishAndStoreOverflow(&aMetrics);
// Reflow the single anon block child.
nsReflowStatus childStatus;
nsSize availSize(aReflowState.ComputedWidth(), NS_UNCONSTRAINEDSIZE);
nsIFrame* childFrame = mFrames.FirstChild();
NS_ASSERTION(!childFrame->GetNextSibling(), "HTML canvas should have 1 kid");
nsHTMLReflowMetrics childDesiredSize(aReflowState.GetWritingMode(), aMetrics.mFlags);
nsHTMLReflowState childReflowState(aPresContext, aReflowState, childFrame,
availSize);
ReflowChild(childFrame, aPresContext, childDesiredSize, childReflowState,
0, 0, 0, childStatus, nullptr);
FinishReflowChild(childFrame, aPresContext, childDesiredSize,
&childReflowState, 0, 0, 0);
NS_FRAME_TRACE(NS_FRAME_TRACE_CALLS,
("exit nsHTMLCanvasFrame::Reflow: size=%d,%d",
aMetrics.Width(), aMetrics.Height()));
NS_FRAME_SET_TRUNCATION(aStatus, aReflowState, aMetrics);
}
// FIXME taken from nsImageFrame, but then had splittable frame stuff
// removed. That needs to be fixed.
nsRect
nsHTMLCanvasFrame::GetInnerArea() const
{
nsRect r;
r.x = mBorderPadding.left;
r.y = mBorderPadding.top;
r.width = mRect.width - mBorderPadding.left - mBorderPadding.right;
r.height = mRect.height - mBorderPadding.top - mBorderPadding.bottom;
return r;
}
already_AddRefed<Layer>
nsHTMLCanvasFrame::BuildLayer(nsDisplayListBuilder* aBuilder,
LayerManager* aManager,
nsDisplayItem* aItem,
const ContainerLayerParameters& aContainerParameters)
{
nsRect area = GetContentRect() - GetPosition() + aItem->ToReferenceFrame();
HTMLCanvasElement* element = static_cast<HTMLCanvasElement*>(GetContent());
nsIntSize canvasSize = GetCanvasSize();
nsPresContext* presContext = PresContext();
element->HandlePrintCallback(presContext->Type());
if (canvasSize.width <= 0 || canvasSize.height <= 0 || area.IsEmpty())
return nullptr;
CanvasLayer* oldLayer = static_cast<CanvasLayer*>
(aManager->GetLayerBuilder()->GetLeafLayerFor(aBuilder, aItem));
nsRefPtr<CanvasLayer> layer = element->GetCanvasLayer(aBuilder, oldLayer, aManager);
if (!layer)
return nullptr;
gfxRect r = gfxRect(presContext->AppUnitsToGfxUnits(area.x),
presContext->AppUnitsToGfxUnits(area.y),
presContext->AppUnitsToGfxUnits(area.width),
presContext->AppUnitsToGfxUnits(area.height));
// Transform the canvas into the right place
gfx::Matrix transform;
gfxPoint p = r.TopLeft() + aContainerParameters.mOffset;
transform.Translate(p.x, p.y);
transform.Scale(r.Width()/canvasSize.width, r.Height()/canvasSize.height);
layer->SetBaseTransform(gfx::Matrix4x4::From2D(transform));
layer->SetFilter(nsLayoutUtils::GetGraphicsFilterForFrame(this));
return layer.forget();
}
void
nsHTMLCanvasFrame::BuildDisplayList(nsDisplayListBuilder* aBuilder,
const nsRect& aDirtyRect,
const nsDisplayListSet& aLists)
{
if (!IsVisibleForPainting(aBuilder))
return;
DisplayBorderBackgroundOutline(aBuilder, aLists);
DisplayListClipState::AutoClipContainingBlockDescendantsToContentBox
clip(aBuilder, this, DisplayListClipState::ASSUME_DRAWING_RESTRICTED_TO_CONTENT_RECT);
aLists.Content()->AppendNewToTop(
new (aBuilder) nsDisplayCanvas(aBuilder, this));
DisplaySelectionOverlay(aBuilder, aLists.Content(),
nsISelectionDisplay::DISPLAY_IMAGES);
}
nsIAtom*
nsHTMLCanvasFrame::GetType() const
{
return nsGkAtoms::HTMLCanvasFrame;
}
// get the offset into the content area of the image where aImg starts if it is a continuation.
// from nsImageFrame
nscoord
nsHTMLCanvasFrame::GetContinuationOffset(nscoord* aWidth) const
{
nscoord offset = 0;
if (aWidth) {
*aWidth = 0;
}
if (GetPrevInFlow()) {
for (nsIFrame* prevInFlow = GetPrevInFlow() ; prevInFlow; prevInFlow = prevInFlow->GetPrevInFlow()) {
nsRect rect = prevInFlow->GetRect();
if (aWidth) {
*aWidth = rect.width;
}
offset += rect.height;
}
offset -= mBorderPadding.top;
offset = std::max(0, offset);
}
return offset;
}
#ifdef ACCESSIBILITY
a11y::AccType
nsHTMLCanvasFrame::AccessibleType()
{
return a11y::eHTMLCanvasType;
}
#endif
#ifdef DEBUG_FRAME_DUMP
nsresult
nsHTMLCanvasFrame::GetFrameName(nsAString& aResult) const
{
return MakeFrameName(NS_LITERAL_STRING("HTMLCanvas"), aResult);
}
#endif