gecko-dev/dom/html/HTMLCanvasElement.cpp
2017-04-13 09:14:34 -07:00

1512 lines
39 KiB
C++

/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* 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/. */
#include "mozilla/dom/HTMLCanvasElement.h"
#include "ImageEncoder.h"
#include "jsapi.h"
#include "jsfriendapi.h"
#include "Layers.h"
#include "MediaSegment.h"
#include "mozilla/Assertions.h"
#include "mozilla/Base64.h"
#include "mozilla/CheckedInt.h"
#include "mozilla/dom/CanvasCaptureMediaStream.h"
#include "mozilla/dom/CanvasRenderingContext2D.h"
#include "mozilla/dom/File.h"
#include "mozilla/dom/HTMLCanvasElementBinding.h"
#include "mozilla/dom/MediaStreamTrack.h"
#include "mozilla/dom/MouseEvent.h"
#include "mozilla/dom/OffscreenCanvas.h"
#include "mozilla/EventDispatcher.h"
#include "mozilla/gfx/Rect.h"
#include "mozilla/layers/AsyncCanvasRenderer.h"
#include "mozilla/MouseEvents.h"
#include "mozilla/Preferences.h"
#include "mozilla/Telemetry.h"
#include "nsAttrValueInlines.h"
#include "nsContentUtils.h"
#include "nsDisplayList.h"
#include "nsDOMJSUtils.h"
#include "nsIScriptSecurityManager.h"
#include "nsITimer.h"
#include "nsIWritablePropertyBag2.h"
#include "nsIXPConnect.h"
#include "nsJSUtils.h"
#include "nsLayoutUtils.h"
#include "nsMathUtils.h"
#include "nsNetUtil.h"
#include "nsRefreshDriver.h"
#include "nsStreamUtils.h"
#include "ActiveLayerTracker.h"
#include "VRManagerChild.h"
#include "WebGL1Context.h"
#include "WebGL2Context.h"
using namespace mozilla::layers;
using namespace mozilla::gfx;
NS_IMPL_NS_NEW_HTML_ELEMENT(Canvas)
namespace mozilla {
namespace dom {
class RequestedFrameRefreshObserver : public nsARefreshObserver
{
NS_INLINE_DECL_THREADSAFE_REFCOUNTING(RequestedFrameRefreshObserver, override)
public:
RequestedFrameRefreshObserver(HTMLCanvasElement* const aOwningElement,
nsRefreshDriver* aRefreshDriver)
: mRegistered(false),
mOwningElement(aOwningElement),
mRefreshDriver(aRefreshDriver)
{
MOZ_ASSERT(mOwningElement);
}
static already_AddRefed<DataSourceSurface>
CopySurface(const RefPtr<SourceSurface>& aSurface)
{
RefPtr<DataSourceSurface> data = aSurface->GetDataSurface();
if (!data) {
return nullptr;
}
DataSourceSurface::ScopedMap read(data, DataSourceSurface::READ);
if (!read.IsMapped()) {
return nullptr;
}
RefPtr<DataSourceSurface> copy =
Factory::CreateDataSourceSurfaceWithStride(data->GetSize(),
data->GetFormat(),
read.GetStride());
if (!copy) {
return nullptr;
}
DataSourceSurface::ScopedMap write(copy, DataSourceSurface::WRITE);
if (!write.IsMapped()) {
return nullptr;
}
MOZ_ASSERT(read.GetStride() == write.GetStride());
MOZ_ASSERT(data->GetSize() == copy->GetSize());
MOZ_ASSERT(data->GetFormat() == copy->GetFormat());
memcpy(write.GetData(), read.GetData(),
write.GetStride() * copy->GetSize().height);
return copy.forget();
}
void WillRefresh(TimeStamp aTime) override
{
MOZ_ASSERT(NS_IsMainThread());
PROFILER_LABEL("HTMLCanvasElement", "FrameCapture", js::ProfileEntry::Category::OTHER);
if (!mOwningElement) {
return;
}
if (mOwningElement->IsWriteOnly()) {
return;
}
if (mOwningElement->IsContextCleanForFrameCapture()) {
return;
}
mOwningElement->ProcessDestroyedFrameListeners();
if (!mOwningElement->IsFrameCaptureRequested()) {
return;
}
RefPtr<SourceSurface> snapshot;
{
PROFILER_LABEL("HTMLCanvasElement", "GetSnapshot", js::ProfileEntry::Category::OTHER);
snapshot = mOwningElement->GetSurfaceSnapshot(nullptr);
if (!snapshot) {
return;
}
}
RefPtr<DataSourceSurface> copy;
{
PROFILER_LABEL("HTMLCanvasElement", "CopySnapshot", js::ProfileEntry::Category::OTHER);
copy = CopySurface(snapshot);
if (!copy) {
return;
}
}
{
PROFILER_LABEL("HTMLCanvasElement", "SetFrame", js::ProfileEntry::Category::OTHER);
mOwningElement->SetFrameCapture(copy.forget(), aTime);
mOwningElement->MarkContextCleanForFrameCapture();
}
}
void DetachFromRefreshDriver()
{
MOZ_ASSERT(mOwningElement);
MOZ_ASSERT(mRefreshDriver);
Unregister();
mRefreshDriver = nullptr;
}
void Register()
{
if (mRegistered) {
return;
}
MOZ_ASSERT(mRefreshDriver);
if (mRefreshDriver) {
mRefreshDriver->AddRefreshObserver(this, FlushType::Display);
mRegistered = true;
}
}
void Unregister()
{
if (!mRegistered) {
return;
}
MOZ_ASSERT(mRefreshDriver);
if (mRefreshDriver) {
mRefreshDriver->RemoveRefreshObserver(this, FlushType::Display);
mRegistered = false;
}
}
private:
virtual ~RequestedFrameRefreshObserver()
{
MOZ_ASSERT(!mRefreshDriver);
MOZ_ASSERT(!mRegistered);
}
bool mRegistered;
HTMLCanvasElement* const mOwningElement;
RefPtr<nsRefreshDriver> mRefreshDriver;
};
// ---------------------------------------------------------------------------
NS_IMPL_CYCLE_COLLECTION_WRAPPERCACHE(HTMLCanvasPrintState, mCanvas,
mContext, mCallback)
NS_IMPL_CYCLE_COLLECTION_ROOT_NATIVE(HTMLCanvasPrintState, AddRef)
NS_IMPL_CYCLE_COLLECTION_UNROOT_NATIVE(HTMLCanvasPrintState, Release)
HTMLCanvasPrintState::HTMLCanvasPrintState(HTMLCanvasElement* aCanvas,
nsICanvasRenderingContextInternal* aContext,
nsITimerCallback* aCallback)
: mIsDone(false), mPendingNotify(false), mCanvas(aCanvas),
mContext(aContext), mCallback(aCallback)
{
}
HTMLCanvasPrintState::~HTMLCanvasPrintState()
{
}
/* virtual */ JSObject*
HTMLCanvasPrintState::WrapObject(JSContext* aCx, JS::Handle<JSObject*> aGivenProto)
{
return MozCanvasPrintStateBinding::Wrap(aCx, this, aGivenProto);
}
nsISupports*
HTMLCanvasPrintState::Context() const
{
return mContext;
}
void
HTMLCanvasPrintState::Done()
{
if (!mPendingNotify && !mIsDone) {
// The canvas needs to be invalidated for printing reftests on linux to
// work.
if (mCanvas) {
mCanvas->InvalidateCanvas();
}
RefPtr<nsRunnableMethod<HTMLCanvasPrintState> > doneEvent =
NewRunnableMethod(this, &HTMLCanvasPrintState::NotifyDone);
if (NS_SUCCEEDED(NS_DispatchToCurrentThread(doneEvent))) {
mPendingNotify = true;
}
}
}
void
HTMLCanvasPrintState::NotifyDone()
{
mIsDone = true;
mPendingNotify = false;
if (mCallback) {
mCallback->Notify(nullptr);
}
}
// ---------------------------------------------------------------------------
HTMLCanvasElementObserver::HTMLCanvasElementObserver(HTMLCanvasElement* aElement)
: mElement(aElement)
{
RegisterVisibilityChangeEvent();
RegisterMemoryPressureEvent();
}
HTMLCanvasElementObserver::~HTMLCanvasElementObserver()
{
Destroy();
}
void
HTMLCanvasElementObserver::Destroy()
{
UnregisterMemoryPressureEvent();
UnregisterVisibilityChangeEvent();
mElement = nullptr;
}
void
HTMLCanvasElementObserver::RegisterVisibilityChangeEvent()
{
if (!mElement) {
return;
}
nsIDocument* document = mElement->OwnerDoc();
document->AddSystemEventListener(NS_LITERAL_STRING("visibilitychange"),
this, true, false);
}
void
HTMLCanvasElementObserver::UnregisterVisibilityChangeEvent()
{
if (!mElement) {
return;
}
nsIDocument* document = mElement->OwnerDoc();
document->RemoveSystemEventListener(NS_LITERAL_STRING("visibilitychange"),
this, true);
}
void
HTMLCanvasElementObserver::RegisterMemoryPressureEvent()
{
if (!mElement) {
return;
}
nsCOMPtr<nsIObserverService> observerService =
mozilla::services::GetObserverService();
MOZ_ASSERT(observerService);
if (observerService)
observerService->AddObserver(this, "memory-pressure", false);
}
void
HTMLCanvasElementObserver::UnregisterMemoryPressureEvent()
{
if (!mElement) {
return;
}
nsCOMPtr<nsIObserverService> observerService =
mozilla::services::GetObserverService();
// Do not assert on observerService here. This might be triggered by
// the cycle collector at a late enough time, that XPCOM services are
// no longer available. See bug 1029504.
if (observerService)
observerService->RemoveObserver(this, "memory-pressure");
}
NS_IMETHODIMP
HTMLCanvasElementObserver::Observe(nsISupports*, const char* aTopic, const char16_t*)
{
if (!mElement || strcmp(aTopic, "memory-pressure")) {
return NS_OK;
}
mElement->OnMemoryPressure();
return NS_OK;
}
NS_IMETHODIMP
HTMLCanvasElementObserver::HandleEvent(nsIDOMEvent* aEvent)
{
nsAutoString type;
aEvent->GetType(type);
if (!mElement || !type.EqualsLiteral("visibilitychange")) {
return NS_OK;
}
mElement->OnVisibilityChange();
return NS_OK;
}
NS_IMPL_ISUPPORTS(HTMLCanvasElementObserver, nsIObserver)
// ---------------------------------------------------------------------------
HTMLCanvasElement::HTMLCanvasElement(already_AddRefed<mozilla::dom::NodeInfo>& aNodeInfo)
: nsGenericHTMLElement(aNodeInfo),
mResetLayer(true) ,
mVRPresentationActive(false),
mWriteOnly(false)
{}
HTMLCanvasElement::~HTMLCanvasElement()
{
if (mContextObserver) {
mContextObserver->Destroy();
mContextObserver = nullptr;
}
ResetPrintCallback();
if (mRequestedFrameRefreshObserver) {
mRequestedFrameRefreshObserver->DetachFromRefreshDriver();
}
if (mAsyncCanvasRenderer) {
mAsyncCanvasRenderer->mHTMLCanvasElement = nullptr;
}
}
NS_IMPL_CYCLE_COLLECTION_INHERITED(HTMLCanvasElement, nsGenericHTMLElement,
mCurrentContext, mPrintCallback,
mPrintState, mOriginalCanvas,
mOffscreenCanvas)
NS_IMPL_ADDREF_INHERITED(HTMLCanvasElement, Element)
NS_IMPL_RELEASE_INHERITED(HTMLCanvasElement, Element)
NS_INTERFACE_TABLE_HEAD_CYCLE_COLLECTION_INHERITED(HTMLCanvasElement)
NS_INTERFACE_TABLE_INHERITED(HTMLCanvasElement, nsIDOMHTMLCanvasElement)
NS_INTERFACE_TABLE_TAIL_INHERITING(nsGenericHTMLElement)
NS_IMPL_ELEMENT_CLONE(HTMLCanvasElement)
/* virtual */ JSObject*
HTMLCanvasElement::WrapNode(JSContext* aCx, JS::Handle<JSObject*> aGivenProto)
{
return HTMLCanvasElementBinding::Wrap(aCx, this, aGivenProto);
}
already_AddRefed<nsICanvasRenderingContextInternal>
HTMLCanvasElement::CreateContext(CanvasContextType aContextType)
{
// Note that the compositor backend will be LAYERS_NONE if there is no widget.
RefPtr<nsICanvasRenderingContextInternal> ret =
CreateContextHelper(aContextType, GetCompositorBackendType());
// Add Observer for webgl canvas.
if (aContextType == CanvasContextType::WebGL1 ||
aContextType == CanvasContextType::WebGL2) {
if (!mContextObserver) {
mContextObserver = new HTMLCanvasElementObserver(this);
}
}
ret->SetCanvasElement(this);
return ret.forget();
}
nsIntSize
HTMLCanvasElement::GetWidthHeight()
{
nsIntSize size(DEFAULT_CANVAS_WIDTH, DEFAULT_CANVAS_HEIGHT);
const nsAttrValue* value;
if ((value = GetParsedAttr(nsGkAtoms::width)) &&
value->Type() == nsAttrValue::eInteger)
{
size.width = value->GetIntegerValue();
}
if ((value = GetParsedAttr(nsGkAtoms::height)) &&
value->Type() == nsAttrValue::eInteger)
{
size.height = value->GetIntegerValue();
}
MOZ_ASSERT(size.width >= 0 && size.height >= 0,
"we should've required <canvas> width/height attrs to be "
"unsigned (non-negative) values");
return size;
}
NS_IMPL_UINT_ATTR_DEFAULT_VALUE(HTMLCanvasElement, Width, width, DEFAULT_CANVAS_WIDTH)
NS_IMPL_UINT_ATTR_DEFAULT_VALUE(HTMLCanvasElement, Height, height, DEFAULT_CANVAS_HEIGHT)
NS_IMPL_BOOL_ATTR(HTMLCanvasElement, MozOpaque, moz_opaque)
nsresult
HTMLCanvasElement::SetAttr(int32_t aNameSpaceID, nsIAtom* aName,
nsIAtom* aPrefix, const nsAString& aValue,
bool aNotify)
{
nsresult rv = nsGenericHTMLElement::SetAttr(aNameSpaceID, aName, aPrefix, aValue,
aNotify);
if (NS_SUCCEEDED(rv) && mCurrentContext &&
aNameSpaceID == kNameSpaceID_None &&
(aName == nsGkAtoms::width || aName == nsGkAtoms::height || aName == nsGkAtoms::moz_opaque))
{
ErrorResult dummy;
rv = UpdateContext(nullptr, JS::NullHandleValue, dummy);
NS_ENSURE_SUCCESS(rv, rv);
}
return rv;
}
nsresult
HTMLCanvasElement::UnsetAttr(int32_t aNameSpaceID, nsIAtom* aName,
bool aNotify)
{
nsresult rv = nsGenericHTMLElement::UnsetAttr(aNameSpaceID, aName, aNotify);
if (NS_SUCCEEDED(rv) && mCurrentContext &&
aNameSpaceID == kNameSpaceID_None &&
(aName == nsGkAtoms::width || aName == nsGkAtoms::height || aName == nsGkAtoms::moz_opaque))
{
ErrorResult dummy;
rv = UpdateContext(nullptr, JS::NullHandleValue, dummy);
NS_ENSURE_SUCCESS(rv, rv);
}
return rv;
}
void
HTMLCanvasElement::HandlePrintCallback(nsPresContext::nsPresContextType aType)
{
// Only call the print callback here if 1) we're in a print testing mode or
// print preview mode, 2) the canvas has a print callback and 3) the callback
// hasn't already been called. For real printing the callback is handled in
// nsSimplePageSequenceFrame::PrePrintNextPage.
if ((aType == nsPresContext::eContext_PageLayout ||
aType == nsPresContext::eContext_PrintPreview) &&
!mPrintState && GetMozPrintCallback()) {
DispatchPrintCallback(nullptr);
}
}
nsresult
HTMLCanvasElement::DispatchPrintCallback(nsITimerCallback* aCallback)
{
// For print reftests the context may not be initialized yet, so get a context
// so mCurrentContext is set.
if (!mCurrentContext) {
nsresult rv;
nsCOMPtr<nsISupports> context;
rv = GetContext(NS_LITERAL_STRING("2d"), getter_AddRefs(context));
NS_ENSURE_SUCCESS(rv, rv);
}
mPrintState = new HTMLCanvasPrintState(this, mCurrentContext, aCallback);
RefPtr<nsRunnableMethod<HTMLCanvasElement> > renderEvent =
NewRunnableMethod(this, &HTMLCanvasElement::CallPrintCallback);
return OwnerDoc()->Dispatch("HTMLCanvasElement::CallPrintCallback",
TaskCategory::Other,
renderEvent.forget());
}
void
HTMLCanvasElement::CallPrintCallback()
{
ErrorResult rv;
GetMozPrintCallback()->Call(*mPrintState, rv);
}
void
HTMLCanvasElement::ResetPrintCallback()
{
if (mPrintState) {
mPrintState = nullptr;
}
}
bool
HTMLCanvasElement::IsPrintCallbackDone()
{
if (mPrintState == nullptr) {
return true;
}
return mPrintState->mIsDone;
}
HTMLCanvasElement*
HTMLCanvasElement::GetOriginalCanvas()
{
return mOriginalCanvas ? mOriginalCanvas.get() : this;
}
nsresult
HTMLCanvasElement::CopyInnerTo(Element* aDest)
{
nsresult rv = nsGenericHTMLElement::CopyInnerTo(aDest);
NS_ENSURE_SUCCESS(rv, rv);
if (aDest->OwnerDoc()->IsStaticDocument()) {
HTMLCanvasElement* dest = static_cast<HTMLCanvasElement*>(aDest);
dest->mOriginalCanvas = this;
nsCOMPtr<nsISupports> cxt;
dest->GetContext(NS_LITERAL_STRING("2d"), getter_AddRefs(cxt));
RefPtr<CanvasRenderingContext2D> context2d =
static_cast<CanvasRenderingContext2D*>(cxt.get());
if (context2d && !mPrintCallback) {
CanvasImageSource source;
source.SetAsHTMLCanvasElement() = this;
ErrorResult err;
context2d->DrawImage(source,
0.0, 0.0, err);
rv = err.StealNSResult();
}
}
return rv;
}
nsresult HTMLCanvasElement::GetEventTargetParent(EventChainPreVisitor& aVisitor)
{
if (aVisitor.mEvent->mClass == eMouseEventClass) {
WidgetMouseEventBase* evt = (WidgetMouseEventBase*)aVisitor.mEvent;
if (mCurrentContext) {
nsIFrame *frame = GetPrimaryFrame();
if (!frame)
return NS_OK;
nsPoint ptInRoot = nsLayoutUtils::GetEventCoordinatesRelativeTo(evt, frame);
nsRect paddingRect = frame->GetContentRectRelativeToSelf();
Point hitpoint;
hitpoint.x = (ptInRoot.x - paddingRect.x) / AppUnitsPerCSSPixel();
hitpoint.y = (ptInRoot.y - paddingRect.y) / AppUnitsPerCSSPixel();
evt->region = mCurrentContext->GetHitRegion(hitpoint);
aVisitor.mCanHandle = true;
}
}
return nsGenericHTMLElement::GetEventTargetParent(aVisitor);
}
nsChangeHint
HTMLCanvasElement::GetAttributeChangeHint(const nsIAtom* aAttribute,
int32_t aModType) const
{
nsChangeHint retval =
nsGenericHTMLElement::GetAttributeChangeHint(aAttribute, aModType);
if (aAttribute == nsGkAtoms::width ||
aAttribute == nsGkAtoms::height)
{
retval |= NS_STYLE_HINT_REFLOW;
} else if (aAttribute == nsGkAtoms::moz_opaque)
{
retval |= NS_STYLE_HINT_VISUAL;
}
return retval;
}
bool
HTMLCanvasElement::ParseAttribute(int32_t aNamespaceID,
nsIAtom* aAttribute,
const nsAString& aValue,
nsAttrValue& aResult)
{
if (aNamespaceID == kNameSpaceID_None &&
(aAttribute == nsGkAtoms::width || aAttribute == nsGkAtoms::height)) {
return aResult.ParseNonNegativeIntValue(aValue);
}
return nsGenericHTMLElement::ParseAttribute(aNamespaceID, aAttribute, aValue,
aResult);
}
void
HTMLCanvasElement::ToDataURL(JSContext* aCx, const nsAString& aType,
JS::Handle<JS::Value> aParams,
nsAString& aDataURL,
ErrorResult& aRv)
{
// do a trust check if this is a write-only canvas
if (mWriteOnly &&
!nsContentUtils::CallerHasPermission(aCx, NS_LITERAL_STRING("<all_urls>"))) {
aRv.Throw(NS_ERROR_DOM_SECURITY_ERR);
return;
}
aRv = ToDataURLImpl(aCx, aType, aParams, aDataURL);
}
void
HTMLCanvasElement::SetMozPrintCallback(PrintCallback* aCallback)
{
mPrintCallback = aCallback;
}
PrintCallback*
HTMLCanvasElement::GetMozPrintCallback() const
{
if (mOriginalCanvas) {
return mOriginalCanvas->GetMozPrintCallback();
}
return mPrintCallback;
}
class CanvasCaptureTrackSource : public MediaStreamTrackSource
{
public:
NS_DECL_ISUPPORTS_INHERITED
NS_DECL_CYCLE_COLLECTION_CLASS_INHERITED(CanvasCaptureTrackSource,
MediaStreamTrackSource)
CanvasCaptureTrackSource(nsIPrincipal* aPrincipal,
CanvasCaptureMediaStream* aCaptureStream)
: MediaStreamTrackSource(aPrincipal, nsString())
, mCaptureStream(aCaptureStream) {}
MediaSourceEnum GetMediaSource() const override
{
return MediaSourceEnum::Other;
}
void Stop() override
{
if (!mCaptureStream) {
NS_ERROR("No stream");
return;
}
mCaptureStream->StopCapture();
}
private:
virtual ~CanvasCaptureTrackSource() {}
RefPtr<CanvasCaptureMediaStream> mCaptureStream;
};
NS_IMPL_ADDREF_INHERITED(CanvasCaptureTrackSource,
MediaStreamTrackSource)
NS_IMPL_RELEASE_INHERITED(CanvasCaptureTrackSource,
MediaStreamTrackSource)
NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION_INHERITED(CanvasCaptureTrackSource)
NS_INTERFACE_MAP_END_INHERITING(MediaStreamTrackSource)
NS_IMPL_CYCLE_COLLECTION_INHERITED(CanvasCaptureTrackSource,
MediaStreamTrackSource,
mCaptureStream)
already_AddRefed<CanvasCaptureMediaStream>
HTMLCanvasElement::CaptureStream(const Optional<double>& aFrameRate,
ErrorResult& aRv)
{
if (IsWriteOnly()) {
aRv.Throw(NS_ERROR_DOM_SECURITY_ERR);
return nullptr;
}
nsPIDOMWindowInner* window = OwnerDoc()->GetInnerWindow();
if (!window) {
aRv.Throw(NS_ERROR_FAILURE);
return nullptr;
}
if (!mCurrentContext) {
aRv.Throw(NS_ERROR_NOT_INITIALIZED);
return nullptr;
}
RefPtr<CanvasCaptureMediaStream> stream =
CanvasCaptureMediaStream::CreateSourceStream(window, this);
if (!stream) {
aRv.Throw(NS_ERROR_FAILURE);
return nullptr;
}
TrackID videoTrackId = 1;
nsCOMPtr<nsIPrincipal> principal = NodePrincipal();
nsresult rv =
stream->Init(aFrameRate, videoTrackId, principal);
if (NS_FAILED(rv)) {
aRv.Throw(rv);
return nullptr;
}
RefPtr<MediaStreamTrack> track =
stream->CreateDOMTrack(videoTrackId, MediaSegment::VIDEO,
new CanvasCaptureTrackSource(principal, stream));
stream->AddTrackInternal(track);
rv = RegisterFrameCaptureListener(stream->FrameCaptureListener());
if (NS_FAILED(rv)) {
aRv.Throw(rv);
return nullptr;
}
return stream.forget();
}
nsresult
HTMLCanvasElement::ExtractData(nsAString& aType,
const nsAString& aOptions,
nsIInputStream** aStream)
{
return ImageEncoder::ExtractData(aType,
aOptions,
GetSize(),
mCurrentContext,
mAsyncCanvasRenderer,
aStream);
}
nsresult
HTMLCanvasElement::ToDataURLImpl(JSContext* aCx,
const nsAString& aMimeType,
const JS::Value& aEncoderOptions,
nsAString& aDataURL)
{
nsIntSize size = GetWidthHeight();
if (size.height == 0 || size.width == 0) {
aDataURL = NS_LITERAL_STRING("data:,");
return NS_OK;
}
nsAutoString type;
nsContentUtils::ASCIIToLower(aMimeType, type);
nsAutoString params;
bool usingCustomParseOptions;
nsresult rv =
ParseParams(aCx, type, aEncoderOptions, params, &usingCustomParseOptions);
if (NS_FAILED(rv)) {
return rv;
}
nsCOMPtr<nsIInputStream> stream;
rv = ExtractData(type, params, getter_AddRefs(stream));
// If there are unrecognized custom parse options, we should fall back to
// the default values for the encoder without any options at all.
if (rv == NS_ERROR_INVALID_ARG && usingCustomParseOptions) {
rv = ExtractData(type, EmptyString(), getter_AddRefs(stream));
}
NS_ENSURE_SUCCESS(rv, rv);
// build data URL string
aDataURL = NS_LITERAL_STRING("data:") + type + NS_LITERAL_STRING(";base64,");
uint64_t count;
rv = stream->Available(&count);
NS_ENSURE_SUCCESS(rv, rv);
NS_ENSURE_TRUE(count <= UINT32_MAX, NS_ERROR_FILE_TOO_BIG);
return Base64EncodeInputStream(stream, aDataURL, (uint32_t)count, aDataURL.Length());
}
void
HTMLCanvasElement::ToBlob(JSContext* aCx,
BlobCallback& aCallback,
const nsAString& aType,
JS::Handle<JS::Value> aParams,
ErrorResult& aRv)
{
// do a trust check if this is a write-only canvas
if (mWriteOnly &&
!nsContentUtils::CallerHasPermission(aCx, NS_LITERAL_STRING("<all_urls>"))) {
aRv.Throw(NS_ERROR_DOM_SECURITY_ERR);
return;
}
nsCOMPtr<nsIGlobalObject> global = OwnerDoc()->GetScopeObject();
MOZ_ASSERT(global);
nsIntSize elemSize = GetWidthHeight();
if (elemSize.width == 0 || elemSize.height == 0) {
// According to spec, blob should return null if either its horizontal
// dimension or its vertical dimension is zero. See link below.
// https://html.spec.whatwg.org/multipage/scripting.html#dom-canvas-toblob
OwnerDoc()->Dispatch("FireNullBlobEvent",
TaskCategory::Other,
NewRunnableMethod<Blob*, const char*>(
&aCallback,
static_cast<void(BlobCallback::*)(
Blob*, const char*)>(&BlobCallback::Call),
nullptr, nullptr));
return;
}
CanvasRenderingContextHelper::ToBlob(aCx, global, aCallback, aType,
aParams, aRv);
}
OffscreenCanvas*
HTMLCanvasElement::TransferControlToOffscreen(ErrorResult& aRv)
{
if (mCurrentContext) {
aRv.Throw(NS_ERROR_DOM_INVALID_STATE_ERR);
return nullptr;
}
if (!mOffscreenCanvas) {
nsIntSize sz = GetWidthHeight();
RefPtr<AsyncCanvasRenderer> renderer = GetAsyncCanvasRenderer();
renderer->SetWidth(sz.width);
renderer->SetHeight(sz.height);
nsCOMPtr<nsIGlobalObject> global =
do_QueryInterface(OwnerDoc()->GetInnerWindow());
mOffscreenCanvas = new OffscreenCanvas(global,
sz.width,
sz.height,
GetCompositorBackendType(),
renderer);
if (mWriteOnly) {
mOffscreenCanvas->SetWriteOnly();
}
if (!mContextObserver) {
mContextObserver = new HTMLCanvasElementObserver(this);
}
} else {
aRv.Throw(NS_ERROR_DOM_INVALID_STATE_ERR);
}
return mOffscreenCanvas;
}
already_AddRefed<File>
HTMLCanvasElement::MozGetAsFile(const nsAString& aName,
const nsAString& aType,
CallerType aCallerType,
ErrorResult& aRv)
{
OwnerDoc()->WarnOnceAbout(nsIDocument::eMozGetAsFile);
// do a trust check if this is a write-only canvas
if (mWriteOnly && aCallerType != CallerType::System) {
aRv.Throw(NS_ERROR_DOM_SECURITY_ERR);
return nullptr;
}
RefPtr<File> file;
aRv = MozGetAsFileImpl(aName, aType, getter_AddRefs(file));
if (NS_WARN_IF(aRv.Failed())) {
return nullptr;
}
return file.forget();
}
nsresult
HTMLCanvasElement::MozGetAsFileImpl(const nsAString& aName,
const nsAString& aType,
File** aResult)
{
nsCOMPtr<nsIInputStream> stream;
nsAutoString type(aType);
nsresult rv = ExtractData(type, EmptyString(), getter_AddRefs(stream));
NS_ENSURE_SUCCESS(rv, rv);
uint64_t imgSize;
rv = stream->Available(&imgSize);
NS_ENSURE_SUCCESS(rv, rv);
NS_ENSURE_TRUE(imgSize <= UINT32_MAX, NS_ERROR_FILE_TOO_BIG);
void* imgData = nullptr;
rv = NS_ReadInputStreamToBuffer(stream, &imgData, (uint32_t)imgSize);
NS_ENSURE_SUCCESS(rv, rv);
JSContext* cx = nsContentUtils::GetCurrentJSContext();
if (cx) {
JS_updateMallocCounter(cx, imgSize);
}
nsCOMPtr<nsPIDOMWindowInner> win = do_QueryInterface(OwnerDoc()->GetScopeObject());
// The File takes ownership of the buffer
RefPtr<File> file =
File::CreateMemoryFile(win, imgData, (uint32_t)imgSize, aName, type,
PR_Now());
file.forget(aResult);
return NS_OK;
}
nsresult
HTMLCanvasElement::GetContext(const nsAString& aContextId,
nsISupports** aContext)
{
ErrorResult rv;
*aContext = GetContext(nullptr, aContextId, JS::NullHandleValue, rv).take();
return rv.StealNSResult();
}
already_AddRefed<nsISupports>
HTMLCanvasElement::GetContext(JSContext* aCx,
const nsAString& aContextId,
JS::Handle<JS::Value> aContextOptions,
ErrorResult& aRv)
{
if (mOffscreenCanvas) {
return nullptr;
}
return CanvasRenderingContextHelper::GetContext(aCx, aContextId,
aContextOptions.isObject() ? aContextOptions : JS::NullHandleValue,
aRv);
}
already_AddRefed<nsISupports>
HTMLCanvasElement::MozGetIPCContext(const nsAString& aContextId,
ErrorResult& aRv)
{
// Note that we're a [ChromeOnly] method, so from JS we can only be called by
// system code.
// We only support 2d shmem contexts for now.
if (!aContextId.EqualsLiteral("2d")) {
aRv.Throw(NS_ERROR_INVALID_ARG);
return nullptr;
}
CanvasContextType contextType = CanvasContextType::Canvas2D;
if (!mCurrentContext) {
// This canvas doesn't have a context yet.
RefPtr<nsICanvasRenderingContextInternal> context;
context = CreateContext(contextType);
if (!context) {
return nullptr;
}
mCurrentContext = context;
mCurrentContext->SetIsIPC(true);
mCurrentContextType = contextType;
ErrorResult dummy;
nsresult rv = UpdateContext(nullptr, JS::NullHandleValue, dummy);
if (NS_WARN_IF(NS_FAILED(rv))) {
aRv.Throw(rv);
return nullptr;
}
} else {
// We already have a context of some type.
if (contextType != mCurrentContextType) {
aRv.Throw(NS_ERROR_INVALID_ARG);
return nullptr;
}
}
nsCOMPtr<nsISupports> context(mCurrentContext);
return context.forget();
}
nsIntSize
HTMLCanvasElement::GetSize()
{
return GetWidthHeight();
}
bool
HTMLCanvasElement::IsWriteOnly()
{
return mWriteOnly;
}
void
HTMLCanvasElement::SetWriteOnly()
{
mWriteOnly = true;
}
void
HTMLCanvasElement::InvalidateCanvasContent(const gfx::Rect* damageRect)
{
// We don't need to flush anything here; if there's no frame or if
// we plan to reframe we don't need to invalidate it anyway.
nsIFrame *frame = GetPrimaryFrame();
if (!frame)
return;
ActiveLayerTracker::NotifyContentChange(frame);
Layer* layer = nullptr;
if (damageRect) {
nsIntSize size = GetWidthHeight();
if (size.width != 0 && size.height != 0) {
gfx::IntRect invalRect = gfx::IntRect::Truncate(*damageRect);
layer = frame->InvalidateLayer(nsDisplayItem::TYPE_CANVAS, &invalRect);
}
} else {
layer = frame->InvalidateLayer(nsDisplayItem::TYPE_CANVAS);
}
if (layer) {
static_cast<CanvasLayer*>(layer)->Updated();
}
/*
* Treat canvas invalidations as animation activity for JS. Frequently
* invalidating a canvas will feed into heuristics and cause JIT code to be
* kept around longer, for smoother animations.
*/
nsCOMPtr<nsIGlobalObject> global =
do_QueryInterface(OwnerDoc()->GetInnerWindow());
if (global) {
if (JSObject *obj = global->GetGlobalJSObject()) {
js::NotifyAnimationActivity(obj);
}
}
}
void
HTMLCanvasElement::InvalidateCanvas()
{
// We don't need to flush anything here; if there's no frame or if
// we plan to reframe we don't need to invalidate it anyway.
nsIFrame *frame = GetPrimaryFrame();
if (!frame)
return;
frame->InvalidateFrame();
}
int32_t
HTMLCanvasElement::CountContexts()
{
if (mCurrentContext)
return 1;
return 0;
}
nsICanvasRenderingContextInternal *
HTMLCanvasElement::GetContextAtIndex(int32_t index)
{
if (mCurrentContext && index == 0)
return mCurrentContext;
return nullptr;
}
bool
HTMLCanvasElement::GetIsOpaque()
{
if (mCurrentContext) {
return mCurrentContext->GetIsOpaque();
}
return GetOpaqueAttr();
}
bool
HTMLCanvasElement::GetOpaqueAttr()
{
return HasAttr(kNameSpaceID_None, nsGkAtoms::moz_opaque);
}
already_AddRefed<Layer>
HTMLCanvasElement::GetCanvasLayer(nsDisplayListBuilder* aBuilder,
Layer *aOldLayer,
LayerManager *aManager)
{
// The address of sOffscreenCanvasLayerUserDataDummy is used as the user
// data key for retained LayerManagers managed by FrameLayerBuilder.
// We don't much care about what value in it, so just assign a dummy
// value for it.
static uint8_t sOffscreenCanvasLayerUserDataDummy = 0;
if (mCurrentContext) {
return mCurrentContext->GetCanvasLayer(aBuilder, aOldLayer, aManager, mVRPresentationActive);
}
if (mOffscreenCanvas) {
if (!mResetLayer &&
aOldLayer && aOldLayer->HasUserData(&sOffscreenCanvasLayerUserDataDummy)) {
RefPtr<Layer> ret = aOldLayer;
return ret.forget();
}
RefPtr<CanvasLayer> layer = aManager->CreateCanvasLayer();
if (!layer) {
NS_WARNING("CreateCanvasLayer failed!");
return nullptr;
}
LayerUserData* userData = nullptr;
layer->SetUserData(&sOffscreenCanvasLayerUserDataDummy, userData);
CanvasLayer::Data data;
data.mRenderer = GetAsyncCanvasRenderer();
data.mSize = GetWidthHeight();
layer->Initialize(data);
layer->Updated();
return layer.forget();
}
return nullptr;
}
bool
HTMLCanvasElement::ShouldForceInactiveLayer(LayerManager* aManager)
{
if (mCurrentContext) {
return mCurrentContext->ShouldForceInactiveLayer(aManager);
}
if (mOffscreenCanvas) {
// TODO: We should handle offscreen canvas case.
return false;
}
return true;
}
void
HTMLCanvasElement::MarkContextClean()
{
if (!mCurrentContext)
return;
mCurrentContext->MarkContextClean();
}
void
HTMLCanvasElement::MarkContextCleanForFrameCapture()
{
if (!mCurrentContext)
return;
mCurrentContext->MarkContextCleanForFrameCapture();
}
bool
HTMLCanvasElement::IsContextCleanForFrameCapture()
{
return mCurrentContext && mCurrentContext->IsContextCleanForFrameCapture();
}
nsresult
HTMLCanvasElement::RegisterFrameCaptureListener(FrameCaptureListener* aListener)
{
WeakPtr<FrameCaptureListener> listener = aListener;
if (mRequestedFrameListeners.Contains(listener)) {
return NS_OK;
}
if (!mRequestedFrameRefreshObserver) {
nsIDocument* doc = OwnerDoc();
if (!doc) {
return NS_ERROR_FAILURE;
}
while (doc->GetParentDocument()) {
doc = doc->GetParentDocument();
}
nsIPresShell* shell = doc->GetShell();
if (!shell) {
return NS_ERROR_FAILURE;
}
nsPresContext* context = shell->GetPresContext();
if (!context) {
return NS_ERROR_FAILURE;
}
context = context->GetRootPresContext();
if (!context) {
return NS_ERROR_FAILURE;
}
nsRefreshDriver* driver = context->RefreshDriver();
if (!driver) {
return NS_ERROR_FAILURE;
}
mRequestedFrameRefreshObserver =
new RequestedFrameRefreshObserver(this, driver);
}
mRequestedFrameListeners.AppendElement(listener);
mRequestedFrameRefreshObserver->Register();
return NS_OK;
}
bool
HTMLCanvasElement::IsFrameCaptureRequested() const
{
for (WeakPtr<FrameCaptureListener> listener : mRequestedFrameListeners) {
if (!listener) {
continue;
}
if (listener->FrameCaptureRequested()) {
return true;
}
}
return false;
}
void
HTMLCanvasElement::ProcessDestroyedFrameListeners()
{
// Loop backwards to allow removing elements in the loop.
for (int i = mRequestedFrameListeners.Length() - 1; i >= 0; --i) {
WeakPtr<FrameCaptureListener> listener = mRequestedFrameListeners[i];
if (!listener) {
// listener was destroyed. Remove it from the list.
mRequestedFrameListeners.RemoveElementAt(i);
continue;
}
}
if (mRequestedFrameListeners.IsEmpty()) {
mRequestedFrameRefreshObserver->Unregister();
}
}
void
HTMLCanvasElement::SetFrameCapture(already_AddRefed<SourceSurface> aSurface,
const TimeStamp& aTime)
{
RefPtr<SourceSurface> surface = aSurface;
RefPtr<SourceSurfaceImage> image = new SourceSurfaceImage(surface->GetSize(), surface);
for (WeakPtr<FrameCaptureListener> listener : mRequestedFrameListeners) {
if (!listener) {
continue;
}
RefPtr<Image> imageRefCopy = image.get();
listener->NewFrame(imageRefCopy.forget(), aTime);
}
}
already_AddRefed<SourceSurface>
HTMLCanvasElement::GetSurfaceSnapshot(gfxAlphaType* const aOutAlphaType)
{
if (!mCurrentContext)
return nullptr;
return mCurrentContext->GetSurfaceSnapshot(aOutAlphaType);
}
AsyncCanvasRenderer*
HTMLCanvasElement::GetAsyncCanvasRenderer()
{
if (!mAsyncCanvasRenderer) {
mAsyncCanvasRenderer = new AsyncCanvasRenderer();
mAsyncCanvasRenderer->mHTMLCanvasElement = this;
}
return mAsyncCanvasRenderer;
}
layers::LayersBackend
HTMLCanvasElement::GetCompositorBackendType() const
{
nsIWidget* docWidget = nsContentUtils::WidgetForDocument(OwnerDoc());
if (docWidget) {
layers::LayerManager* layerManager = docWidget->GetLayerManager();
if (layerManager) {
return layerManager->GetCompositorBackendType();
}
}
return LayersBackend::LAYERS_NONE;
}
void
HTMLCanvasElement::OnVisibilityChange()
{
if (OwnerDoc()->Hidden()) {
return;
}
if (mOffscreenCanvas) {
class Runnable final : public CancelableRunnable
{
public:
explicit Runnable(AsyncCanvasRenderer* aRenderer)
: mRenderer(aRenderer)
{}
NS_IMETHOD Run() override
{
if (mRenderer && mRenderer->mContext) {
mRenderer->mContext->OnVisibilityChange();
}
return NS_OK;
}
void Revoke()
{
mRenderer = nullptr;
}
private:
RefPtr<AsyncCanvasRenderer> mRenderer;
};
RefPtr<nsIRunnable> runnable = new Runnable(mAsyncCanvasRenderer);
nsCOMPtr<nsIThread> activeThread = mAsyncCanvasRenderer->GetActiveThread();
if (activeThread) {
activeThread->Dispatch(runnable, nsIThread::DISPATCH_NORMAL);
}
return;
}
if (mCurrentContext) {
mCurrentContext->OnVisibilityChange();
}
}
void
HTMLCanvasElement::OnMemoryPressure()
{
if (mOffscreenCanvas) {
class Runnable final : public CancelableRunnable
{
public:
explicit Runnable(AsyncCanvasRenderer* aRenderer)
: mRenderer(aRenderer)
{}
NS_IMETHOD Run() override
{
if (mRenderer && mRenderer->mContext) {
mRenderer->mContext->OnMemoryPressure();
}
return NS_OK;
}
void Revoke()
{
mRenderer = nullptr;
}
private:
RefPtr<AsyncCanvasRenderer> mRenderer;
};
RefPtr<nsIRunnable> runnable = new Runnable(mAsyncCanvasRenderer);
nsCOMPtr<nsIThread> activeThread = mAsyncCanvasRenderer->GetActiveThread();
if (activeThread) {
activeThread->Dispatch(runnable, nsIThread::DISPATCH_NORMAL);
}
return;
}
if (mCurrentContext) {
mCurrentContext->OnMemoryPressure();
}
}
/* static */ void
HTMLCanvasElement::SetAttrFromAsyncCanvasRenderer(AsyncCanvasRenderer *aRenderer)
{
HTMLCanvasElement *element = aRenderer->mHTMLCanvasElement;
if (!element) {
return;
}
if (element->GetWidthHeight() == aRenderer->GetSize()) {
return;
}
gfx::IntSize asyncCanvasSize = aRenderer->GetSize();
ErrorResult rv;
element->SetUnsignedIntAttr(nsGkAtoms::width, asyncCanvasSize.width,
DEFAULT_CANVAS_WIDTH, rv);
if (rv.Failed()) {
NS_WARNING("Failed to set width attribute to a canvas element asynchronously.");
}
element->SetUnsignedIntAttr(nsGkAtoms::height, asyncCanvasSize.height,
DEFAULT_CANVAS_HEIGHT, rv);
if (rv.Failed()) {
NS_WARNING("Failed to set height attribute to a canvas element asynchronously.");
}
element->mResetLayer = true;
}
/* static */ void
HTMLCanvasElement::InvalidateFromAsyncCanvasRenderer(AsyncCanvasRenderer *aRenderer)
{
HTMLCanvasElement *element = aRenderer->mHTMLCanvasElement;
if (!element) {
return;
}
element->InvalidateCanvasContent(nullptr);
}
void
HTMLCanvasElement::StartVRPresentation()
{
WebGLContext* webgl = static_cast<WebGLContext*>(GetContextAtIndex(0));
if (!webgl) {
return;
}
if (!webgl->StartVRPresentation()) {
return;
}
mVRPresentationActive = true;
}
void
HTMLCanvasElement::StopVRPresentation()
{
mVRPresentationActive = false;
}
already_AddRefed<layers::SharedSurfaceTextureClient>
HTMLCanvasElement::GetVRFrame()
{
if (GetCurrentContextType() != CanvasContextType::WebGL1 &&
GetCurrentContextType() != CanvasContextType::WebGL2) {
return nullptr;
}
WebGLContext* webgl = static_cast<WebGLContext*>(GetContextAtIndex(0));
if (!webgl) {
return nullptr;
}
return webgl->GetVRFrame();
}
} // namespace dom
} // namespace mozilla