summaryrefslogtreecommitdiff
path: root/layout/generic/nsHTMLCanvasFrame.cpp
diff options
context:
space:
mode:
authorMatt A. Tobin <mattatobin@localhost.localdomain>2018-02-02 04:16:08 -0500
committerMatt A. Tobin <mattatobin@localhost.localdomain>2018-02-02 04:16:08 -0500
commit5f8de423f190bbb79a62f804151bc24824fa32d8 (patch)
tree10027f336435511475e392454359edea8e25895d /layout/generic/nsHTMLCanvasFrame.cpp
parent49ee0794b5d912db1f95dce6eb52d781dc210db5 (diff)
downloaduxp-5f8de423f190bbb79a62f804151bc24824fa32d8.tar.gz
Add m-esr52 at 52.6.0
Diffstat (limited to 'layout/generic/nsHTMLCanvasFrame.cpp')
-rw-r--r--layout/generic/nsHTMLCanvasFrame.cpp437
1 files changed, 437 insertions, 0 deletions
diff --git a/layout/generic/nsHTMLCanvasFrame.cpp b/layout/generic/nsHTMLCanvasFrame.cpp
new file mode 100644
index 0000000000..bad3a710f8
--- /dev/null
+++ b/layout/generic/nsHTMLCanvasFrame.cpp
@@ -0,0 +1,437 @@
+/* -*- 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/Assertions.h"
+#include "mozilla/dom/HTMLCanvasElement.h"
+#include "nsDisplayList.h"
+#include "nsLayoutUtils.h"
+#include "nsStyleUtil.h"
+#include "ImageLayers.h"
+#include "Layers.h"
+#include "ActiveLayerTracker.h"
+
+#include <algorithm>
+
+using namespace mozilla;
+using namespace mozilla::dom;
+using namespace mozilla::layers;
+using namespace mozilla::gfx;
+
+/* Helper for our nsIFrame::GetIntrinsicSize() impl. Takes the result of
+ * "GetCanvasSize()" as a parameter, which may help avoid redundant
+ * indirect calls to GetCanvasSize().
+ *
+ * @param aCanvasSizeInPx The canvas's size in CSS pixels, as returned
+ * by GetCanvasSize().
+ * @return The canvas's intrinsic size, as an IntrinsicSize object.
+ */
+static IntrinsicSize
+IntrinsicSizeFromCanvasSize(const nsIntSize& aCanvasSizeInPx)
+{
+ IntrinsicSize intrinsicSize;
+ intrinsicSize.width.SetCoordValue(
+ nsPresContext::CSSPixelsToAppUnits(aCanvasSizeInPx.width));
+ intrinsicSize.height.SetCoordValue(
+ nsPresContext::CSSPixelsToAppUnits(aCanvasSizeInPx.height));
+
+ return intrinsicSize;
+}
+
+/* Helper for our nsIFrame::GetIntrinsicRatio() impl. Takes the result of
+ * "GetCanvasSize()" as a parameter, which may help avoid redundant
+ * indirect calls to GetCanvasSize().
+ *
+ * @param aCanvasSizeInPx The canvas's size in CSS pixels, as returned
+ * by GetCanvasSize().
+ * @return The canvas's intrinsic ratio, as a nsSize.
+ */
+static nsSize
+IntrinsicRatioFromCanvasSize(const nsIntSize& aCanvasSizeInPx)
+{
+ return nsSize(nsPresContext::CSSPixelsToAppUnits(aCanvasSizeInPx.width),
+ nsPresContext::CSSPixelsToAppUnits(aCanvasSizeInPx.height));
+}
+
+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) override {
+ *aSnap = false;
+ nsHTMLCanvasFrame* f = static_cast<nsHTMLCanvasFrame*>(Frame());
+ HTMLCanvasElement* canvas =
+ HTMLCanvasElement::FromContent(f->GetContent());
+ nsRegion result;
+ if (canvas->GetIsOpaque()) {
+ // OK, the entire region painted by the canvas is opaque. But what is
+ // that region? It's the canvas's "dest rect" (controlled by the
+ // object-fit/object-position CSS properties), clipped to the container's
+ // content box (which is what GetBounds() returns). So, we grab those
+ // rects and intersect them.
+ nsRect constraintRect = GetBounds(aBuilder, aSnap);
+
+ // Need intrinsic size & ratio, for ComputeObjectDestRect:
+ nsIntSize canvasSize = f->GetCanvasSize();
+ IntrinsicSize intrinsicSize = IntrinsicSizeFromCanvasSize(canvasSize);
+ nsSize intrinsicRatio = IntrinsicRatioFromCanvasSize(canvasSize);
+
+ const nsRect destRect =
+ nsLayoutUtils::ComputeObjectDestRect(constraintRect,
+ intrinsicSize, intrinsicRatio,
+ f->StylePosition());
+ return nsRegion(destRect.Intersect(constraintRect));
+ }
+ return result;
+ }
+
+ virtual nsRect GetBounds(nsDisplayListBuilder* aBuilder,
+ bool* aSnap) 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) override
+ {
+ return static_cast<nsHTMLCanvasFrame*>(mFrame)->
+ BuildLayer(aBuilder, aManager, this, aContainerParameters);
+ }
+ virtual LayerState GetLayerState(nsDisplayListBuilder* aBuilder,
+ LayerManager* aManager,
+ const ContainerLayerParameters& aParameters) 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();
+ MOZ_ASSERT(size.width >= 0 && size.height >= 0,
+ "we should've required <canvas> width/height attrs to be "
+ "unsigned (non-negative) values");
+ } else {
+ NS_NOTREACHED("couldn't get canvas size");
+ }
+
+ return size;
+}
+
+/* virtual */ nscoord
+nsHTMLCanvasFrame::GetMinISize(nsRenderingContext *aRenderingContext)
+{
+ // XXX The caller doesn't account for constraints of the height,
+ // min-height, and max-height properties.
+ bool vertical = GetWritingMode().IsVertical();
+ nscoord result = nsPresContext::CSSPixelsToAppUnits(
+ vertical ? GetCanvasSize().height : GetCanvasSize().width);
+ DISPLAY_MIN_WIDTH(this, result);
+ return result;
+}
+
+/* virtual */ nscoord
+nsHTMLCanvasFrame::GetPrefISize(nsRenderingContext *aRenderingContext)
+{
+ // XXX The caller doesn't account for constraints of the height,
+ // min-height, and max-height properties.
+ bool vertical = GetWritingMode().IsVertical();
+ nscoord result = nsPresContext::CSSPixelsToAppUnits(
+ vertical ? GetCanvasSize().height : GetCanvasSize().width);
+ DISPLAY_PREF_WIDTH(this, result);
+ return result;
+}
+
+/* virtual */ IntrinsicSize
+nsHTMLCanvasFrame::GetIntrinsicSize()
+{
+ return IntrinsicSizeFromCanvasSize(GetCanvasSize());
+}
+
+/* virtual */ nsSize
+nsHTMLCanvasFrame::GetIntrinsicRatio()
+{
+ return IntrinsicRatioFromCanvasSize(GetCanvasSize());
+}
+
+/* virtual */
+LogicalSize
+nsHTMLCanvasFrame::ComputeSize(nsRenderingContext *aRenderingContext,
+ WritingMode aWM,
+ const LogicalSize& aCBSize,
+ nscoord aAvailableISize,
+ const LogicalSize& aMargin,
+ const LogicalSize& aBorder,
+ const LogicalSize& aPadding,
+ ComputeSizeFlags 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 ComputeSizeWithIntrinsicDimensions(aRenderingContext, aWM,
+ intrinsicSize, intrinsicRatio,
+ aCBSize, aMargin, aBorder, aPadding,
+ aFlags);
+}
+
+void
+nsHTMLCanvasFrame::Reflow(nsPresContext* aPresContext,
+ ReflowOutput& aMetrics,
+ const ReflowInput& aReflowInput,
+ nsReflowStatus& aStatus)
+{
+ MarkInReflow();
+ DO_GLOBAL_REFLOW_COUNT("nsHTMLCanvasFrame");
+ DISPLAY_REFLOW(aPresContext, this, aReflowInput, aMetrics, aStatus);
+ NS_FRAME_TRACE(NS_FRAME_TRACE_CALLS,
+ ("enter nsHTMLCanvasFrame::Reflow: availSize=%d,%d",
+ aReflowInput.AvailableWidth(), aReflowInput.AvailableHeight()));
+
+ NS_PRECONDITION(mState & NS_FRAME_IN_REFLOW, "frame is not in reflow");
+
+ aStatus = NS_FRAME_COMPLETE;
+
+ WritingMode wm = aReflowInput.GetWritingMode();
+ LogicalSize finalSize(wm,
+ aReflowInput.ComputedISize(),
+ aReflowInput.ComputedBSize());
+
+ // stash this away so we can compute our inner area later
+ mBorderPadding = aReflowInput.ComputedLogicalBorderPadding();
+
+ finalSize.ISize(wm) += mBorderPadding.IStartEnd(wm);
+ finalSize.BSize(wm) += mBorderPadding.BStartEnd(wm);
+
+ if (GetPrevInFlow()) {
+ nscoord y = GetContinuationOffset(&finalSize.ISize(wm));
+ finalSize.BSize(wm) -= y + mBorderPadding.BStart(wm);
+ finalSize.BSize(wm) = std::max(0, finalSize.BSize(wm));
+ }
+
+ aMetrics.SetSize(wm, finalSize);
+ aMetrics.SetOverflowAreasToDesiredBounds();
+ FinishAndStoreOverflow(&aMetrics);
+
+ // Reflow the single anon block child.
+ nsReflowStatus childStatus;
+ nsIFrame* childFrame = mFrames.FirstChild();
+ WritingMode childWM = childFrame->GetWritingMode();
+ LogicalSize availSize = aReflowInput.ComputedSize(childWM);
+ availSize.BSize(childWM) = NS_UNCONSTRAINEDSIZE;
+ NS_ASSERTION(!childFrame->GetNextSibling(), "HTML canvas should have 1 kid");
+ ReflowOutput childDesiredSize(aReflowInput.GetWritingMode(), aMetrics.mFlags);
+ ReflowInput childReflowInput(aPresContext, aReflowInput, childFrame,
+ availSize);
+ ReflowChild(childFrame, aPresContext, childDesiredSize, childReflowInput,
+ 0, 0, 0, childStatus, nullptr);
+ FinishReflowChild(childFrame, aPresContext, childDesiredSize,
+ &childReflowInput, 0, 0, 0);
+
+ NS_FRAME_TRACE(NS_FRAME_TRACE_CALLS,
+ ("exit nsHTMLCanvasFrame::Reflow: size=%d,%d",
+ aMetrics.ISize(wm), aMetrics.BSize(wm)));
+ NS_FRAME_SET_TRUNCATION(aStatus, aReflowInput, aMetrics);
+}
+
+// FIXME taken from nsImageFrame, but then had splittable frame stuff
+// removed. That needs to be fixed.
+// XXXdholbert As in nsImageFrame, this function's clients should probably
+// just be calling GetContentRectRelativeToSelf().
+nsRect
+nsHTMLCanvasFrame::GetInnerArea() const
+{
+ nsMargin bp = mBorderPadding.GetPhysicalMargin(GetWritingMode());
+ nsRect r;
+ r.x = bp.left;
+ r.y = bp.top;
+ r.width = mRect.width - bp.left - bp.right;
+ r.height = mRect.height - bp.top - bp.bottom;
+ return r;
+}
+
+already_AddRefed<Layer>
+nsHTMLCanvasFrame::BuildLayer(nsDisplayListBuilder* aBuilder,
+ LayerManager* aManager,
+ nsDisplayItem* aItem,
+ const ContainerLayerParameters& aContainerParameters)
+{
+ nsRect area = GetContentRectRelativeToSelf() + aItem->ToReferenceFrame();
+ HTMLCanvasElement* element = static_cast<HTMLCanvasElement*>(GetContent());
+ nsIntSize canvasSizeInPx = GetCanvasSize();
+
+ nsPresContext* presContext = PresContext();
+ element->HandlePrintCallback(presContext->Type());
+
+ if (canvasSizeInPx.width <= 0 || canvasSizeInPx.height <= 0 || area.IsEmpty())
+ return nullptr;
+
+ CanvasLayer* oldLayer = static_cast<CanvasLayer*>
+ (aManager->GetLayerBuilder()->GetLeafLayerFor(aBuilder, aItem));
+ RefPtr<Layer> layer = element->GetCanvasLayer(aBuilder, oldLayer, aManager);
+ if (!layer)
+ return nullptr;
+
+ IntrinsicSize intrinsicSize = IntrinsicSizeFromCanvasSize(canvasSizeInPx);
+ nsSize intrinsicRatio = IntrinsicRatioFromCanvasSize(canvasSizeInPx);
+
+ nsRect dest =
+ nsLayoutUtils::ComputeObjectDestRect(area, intrinsicSize, intrinsicRatio,
+ StylePosition());
+
+ gfxRect destGFXRect = presContext->AppUnitsToGfxUnits(dest);
+
+ // Transform the canvas into the right place
+ gfxPoint p = destGFXRect.TopLeft() + aContainerParameters.mOffset;
+ Matrix transform = Matrix::Translation(p.x, p.y);
+ transform.PreScale(destGFXRect.Width() / canvasSizeInPx.width,
+ destGFXRect.Height() / canvasSizeInPx.height);
+ layer->SetBaseTransform(gfx::Matrix4x4::From2D(transform));
+ if (layer->GetType() == layers::Layer::TYPE_CANVAS) {
+ RefPtr<CanvasLayer> canvasLayer = static_cast<CanvasLayer*>(layer.get());
+ canvasLayer->SetSamplingFilter(nsLayoutUtils::GetSamplingFilterForFrame(this));
+ } else if (layer->GetType() == layers::Layer::TYPE_IMAGE) {
+ RefPtr<ImageLayer> imageLayer = static_cast<ImageLayer*>(layer.get());
+ imageLayer->SetSamplingFilter(nsLayoutUtils::GetSamplingFilterForFrame(this));
+ }
+
+ return layer.forget();
+}
+
+void
+nsHTMLCanvasFrame::BuildDisplayList(nsDisplayListBuilder* aBuilder,
+ const nsRect& aDirtyRect,
+ const nsDisplayListSet& aLists)
+{
+ if (!IsVisibleForPainting(aBuilder))
+ return;
+
+ DisplayBorderBackgroundOutline(aBuilder, aLists);
+
+ uint32_t clipFlags =
+ nsStyleUtil::ObjectPropsMightCauseOverflow(StylePosition()) ?
+ 0 : DisplayListClipState::ASSUME_DRAWING_RESTRICTED_TO_CONTENT_RECT;
+
+ DisplayListClipState::AutoClipContainingBlockDescendantsToContentBox
+ clip(aBuilder, this, clipFlags);
+
+ 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.GetPhysicalMargin(GetWritingMode()).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
+