Source/WebKit/GPUProcess/graphics/RemoteGraphicsContextGL.cpp - WebKit - Git at Google

 /*
  * Copyright (C) 2020-2021 Apple Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
  *    documentation and/or other materials provided with the distribution.
  *
  * THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS''
  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
  * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS
  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
  * THE POSSIBILITY OF SUCH DAMAGE.
  */

 #include "config.h"
 #include "RemoteGraphicsContextGL.h"

 #if ENABLE(GPU_PROCESS) && ENABLE(WEBGL)

 #include "GPUConnectionToWebProcess.h"
 #include "QualifiedRenderingResourceIdentifier.h"
 #include "RemoteGraphicsContextGLMessages.h"
 #include "RemoteGraphicsContextGLProxyMessages.h"
 #include "StreamConnectionWorkQueue.h"
 #include <WebCore/GraphicsContextGLOpenGL.h>
 #include <WebCore/NotImplemented.h>
 #include <wtf/MainThread.h>
 #include <wtf/NeverDestroyed.h>

 #if USE(AVFOUNDATION)
 #include <WebCore/GraphicsContextGLCV.h>
 #endif

 namespace WebKit {

 using namespace WebCore;

 // Currently we have one global WebGL processing instance.
 IPC::StreamConnectionWorkQueue& remoteGraphicsContextGLStreamWorkQueue()
 {
     static NeverDestroyed<IPC::StreamConnectionWorkQueue> instance("RemoteGraphicsContextGL work queue");
     return instance.get();
 }

 #if !PLATFORM(COCOA) && !PLATFORM(WIN)
 Ref<RemoteGraphicsContextGL> RemoteGraphicsContextGL::create(GPUConnectionToWebProcess& gpuConnectionToWebProcess, GraphicsContextGLAttributes&& attributes, GraphicsContextGLIdentifier graphicsContextGLIdentifier, RemoteRenderingBackend& renderingBackend, IPC::StreamConnectionBuffer&& stream)
 {
     ASSERT_NOT_REACHED();
     auto instance = adoptRef(*new RemoteGraphicsContextGL(gpuConnectionToWebProcess, graphicsContextGLIdentifier, renderingBackend, WTFMove(stream)));
     instance->initialize(WTFMove(attributes));
     return instance;
 }
 #endif

 RemoteGraphicsContextGL::RemoteGraphicsContextGL(GPUConnectionToWebProcess& gpuConnectionToWebProcess, GraphicsContextGLIdentifier graphicsContextGLIdentifier, RemoteRenderingBackend& renderingBackend, IPC::StreamConnectionBuffer&& stream)
     : m_gpuConnectionToWebProcess(gpuConnectionToWebProcess)
     , m_streamConnection(IPC::StreamServerConnection::create(gpuConnectionToWebProcess.connection(), WTFMove(stream), remoteGraphicsContextGLStreamWorkQueue()))
     , m_graphicsContextGLIdentifier(graphicsContextGLIdentifier)
     , m_renderingBackend(renderingBackend)
     , m_renderingResourcesRequest(ScopedWebGLRenderingResourcesRequest::acquire())
     , m_webProcessIdentifier(gpuConnectionToWebProcess.webProcessIdentifier())
 {
     assertIsMainRunLoop();
 }

 RemoteGraphicsContextGL::~RemoteGraphicsContextGL()
 {
     ASSERT(!m_streamConnection);
     ASSERT(!m_context);
     // Might be destroyed on main thread or stream processing thread.
     m_streamThread.reset();
 }

 void RemoteGraphicsContextGL::initialize(GraphicsContextGLAttributes&& attributes)
 {
     assertIsMainRunLoop();
     remoteGraphicsContextGLStreamWorkQueue().dispatch([attributes = WTFMove(attributes), protectedThis = Ref { *this }]() mutable {
         protectedThis->workQueueInitialize(WTFMove(attributes));
     });
     m_streamConnection->startReceivingMessages(*this, Messages::RemoteGraphicsContextGL::messageReceiverName(), m_graphicsContextGLIdentifier.toUInt64());
 }

 void RemoteGraphicsContextGL::stopListeningForIPC(Ref<RemoteGraphicsContextGL>&& refFromConnection)
 {
     assertIsMainRunLoop();
     m_streamConnection->stopReceivingMessages(Messages::RemoteGraphicsContextGL::messageReceiverName(), m_graphicsContextGLIdentifier.toUInt64());
     remoteGraphicsContextGLStreamWorkQueue().dispatch([protectedThis = WTFMove(refFromConnection)]() {
         protectedThis->workQueueUninitialize();
         protectedThis->m_renderingResourcesRequest = { };
     });
 }

 #if PLATFORM(MAC)
 void RemoteGraphicsContextGL::displayWasReconfigured()
 {
     assertIsMainRunLoop();
     remoteGraphicsContextGLStreamWorkQueue().dispatch([protectedThis = Ref { *this }]() {
         assertIsCurrent(protectedThis->m_streamThread);
         protectedThis->m_context->displayWasReconfigured();
     });
 }
 #endif

 void RemoteGraphicsContextGL::workQueueInitialize(WebCore::GraphicsContextGLAttributes&& attributes)
 {
     m_streamThread.reset();
     assertIsCurrent(m_streamThread);
     platformWorkQueueInitialize(WTFMove(attributes));
     if (m_context) {
         m_context->addClient(*this);
         String extensions = m_context->getString(GraphicsContextGL::EXTENSIONS);
         String requestableExtensions = m_context->getString(ExtensionsGL::REQUESTABLE_EXTENSIONS_ANGLE);
         send(Messages::RemoteGraphicsContextGLProxy::WasCreated(true, remoteGraphicsContextGLStreamWorkQueue().wakeUpSemaphore(), extensions, requestableExtensions));
     } else
         send(Messages::RemoteGraphicsContextGLProxy::WasCreated(false, IPC::Semaphore { }, "", ""));
 }

 void RemoteGraphicsContextGL::workQueueUninitialize()
 {
     assertIsCurrent(m_streamThread);
     m_context = nullptr;
     m_streamConnection = nullptr;
 }

 void RemoteGraphicsContextGL::didComposite()
 {
     assertIsCurrent(m_streamThread);
 }

 void RemoteGraphicsContextGL::forceContextLost()
 {
     assertIsCurrent(m_streamThread);
     send(Messages::RemoteGraphicsContextGLProxy::WasLost());
 }

 void RemoteGraphicsContextGL::recycleContext()
 {
     ASSERT_NOT_REACHED();
 }

 void RemoteGraphicsContextGL::dispatchContextChangedNotification()
 {
     assertIsCurrent(m_streamThread);
     send(Messages::RemoteGraphicsContextGLProxy::WasChanged());
 }

 void RemoteGraphicsContextGL::reshape(int32_t width, int32_t height)
 {
     assertIsCurrent(m_streamThread);
     if (width && height)
         m_context->reshape(width, height);
     else
         forceContextLost();
 }

 #if !PLATFORM(COCOA) && !PLATFORM(WIN)
 void RemoteGraphicsContextGL::prepareForDisplay(CompletionHandler<void()>&& completionHandler)
 {
     assertIsCurrent(m_streamThread);
     notImplemented();
     completionHandler();
 }
 #endif

 void RemoteGraphicsContextGL::synthesizeGLError(uint32_t error)
 {
     assertIsCurrent(m_streamThread);
     m_context->synthesizeGLError(static_cast<GCGLenum>(error));
 }

 void RemoteGraphicsContextGL::getError(CompletionHandler<void(uint32_t)>&& completionHandler)
 {
     assertIsCurrent(m_streamThread);
     completionHandler(static_cast<uint32_t>(m_context->getError()));
 }

 void RemoteGraphicsContextGL::ensureExtensionEnabled(String&& extension)
 {
     assertIsCurrent(m_streamThread);
     m_context->getExtensions().ensureEnabled(extension);
 }

 void RemoteGraphicsContextGL::notifyMarkContextChanged()
 {
     assertIsCurrent(m_streamThread);
     m_context->markContextChanged();
 }

 void RemoteGraphicsContextGL::paintRenderingResultsToCanvas(WebCore::RenderingResourceIdentifier imageBuffer, CompletionHandler<void()>&& completionHandler)
 {
     // Immediately turn the RenderingResourceIdentifier (which is error-prone) to a QualifiedRenderingResourceIdentifier,
     // and use a helper function to make sure that don't accidentally use the RenderingResourceIdentifier (because the helper function can't see it).
     paintRenderingResultsToCanvasWithQualifiedIdentifier({ imageBuffer, m_webProcessIdentifier }, WTFMove(completionHandler));
 }

 void RemoteGraphicsContextGL::paintRenderingResultsToCanvasWithQualifiedIdentifier(QualifiedRenderingResourceIdentifier imageBuffer, CompletionHandler<void()>&& completionHandler)
 {
     assertIsCurrent(m_streamThread);
     paintPixelBufferToImageBuffer(m_context->readRenderingResultsForPainting(), imageBuffer, WTFMove(completionHandler));
 }

 void RemoteGraphicsContextGL::paintCompositedResultsToCanvas(WebCore::RenderingResourceIdentifier imageBuffer, CompletionHandler<void()>&& completionHandler)
 {
     // Immediately turn the RenderingResourceIdentifier (which is error-prone) to a QualifiedRenderingResourceIdentifier,
     // and use a helper function to make sure that don't accidentally use the RenderingResourceIdentifier (because the helper function can't see it).
     paintCompositedResultsToCanvasWithQualifiedIdentifier({ imageBuffer, m_webProcessIdentifier }, WTFMove(completionHandler));
 }

 void RemoteGraphicsContextGL::paintCompositedResultsToCanvasWithQualifiedIdentifier(QualifiedRenderingResourceIdentifier imageBuffer, CompletionHandler<void()>&& completionHandler)
 {
     assertIsCurrent(m_streamThread);
     paintPixelBufferToImageBuffer(m_context->readCompositedResultsForPainting(), imageBuffer, WTFMove(completionHandler));
 }

 void RemoteGraphicsContextGL::paintPixelBufferToImageBuffer(std::optional<WebCore::PixelBuffer>&& pixelBuffer, QualifiedRenderingResourceIdentifier target, CompletionHandler<void()>&& completionHandler)
 {
     assertIsCurrent(m_streamThread);
     // FIXME: We do not have functioning read/write fences in RemoteRenderingBackend. Thus this is synchronous,
     // as are the messages that call these.
     Lock lock;
     Condition conditionVariable;
     bool isFinished = false;
     m_renderingBackend->dispatch([&, contextAttributes = m_context->contextAttributes()]() mutable {
         if (auto imageBuffer = m_renderingBackend->remoteResourceCache().cachedImageBuffer(target)) {
             // Here we do not try to play back pending commands for imageBuffer. Currently this call is only made for empty
             // image buffers and there's no good way to add display lists.
             if (pixelBuffer)
                 GraphicsContextGLOpenGL::paintToCanvas(contextAttributes, WTFMove(*pixelBuffer), imageBuffer->backendSize(), imageBuffer->context());
             else
                 imageBuffer->context().clearRect({ IntPoint(), imageBuffer->backendSize() });
             // Unfortunately "flush" implementation in RemoteRenderingBackend overloads ordering and effects.
             imageBuffer->flushContext();
         }
         Locker locker { lock };
         isFinished = true;
         conditionVariable.notifyOne();
     });
     Locker locker { lock };
     conditionVariable.wait(lock, [&] {
         return isFinished;
     });
     completionHandler();
 }

 void RemoteGraphicsContextGL::copyTextureFromMedia(WebCore::MediaPlayerIdentifier mediaPlayerIdentifier, uint32_t texture, uint32_t target, int32_t level, uint32_t internalFormat, uint32_t format, uint32_t type, bool premultiplyAlpha, bool flipY, CompletionHandler<void(bool)>&& completionHandler)
 {
     assertIsCurrent(m_streamThread);
 #if USE(AVFOUNDATION)
     UNUSED_VARIABLE(premultiplyAlpha);
     ASSERT_UNUSED(target, target == GraphicsContextGL::TEXTURE_2D);

     RetainPtr<CVPixelBufferRef> pixelBuffer;
     auto getPixelBuffer = [&] {
         if (!m_gpuConnectionToWebProcess)
             return;

         if (auto mediaPlayer = m_gpuConnectionToWebProcess->remoteMediaPlayerManagerProxy().mediaPlayer(mediaPlayerIdentifier))
             pixelBuffer = mediaPlayer->pixelBufferForCurrentTime();
     };

     callOnMainRunLoopAndWait(WTFMove(getPixelBuffer));

     if (!pixelBuffer) {
         completionHandler(false);
         return;
     }

     auto contextCV = m_context->asCV();
     if (!contextCV) {
         completionHandler(false);
         return;
     }

     completionHandler(contextCV->copyPixelBufferToTexture(pixelBuffer.get(), texture, level, internalFormat, format, type, GraphicsContextGL::FlipY(flipY)));
 #else
     UNUSED_VARIABLE(mediaPlayerIdentifier);
     UNUSED_VARIABLE(texture);
     UNUSED_VARIABLE(target);
     UNUSED_VARIABLE(level);
     UNUSED_VARIABLE(internalFormat);
     UNUSED_VARIABLE(format);
     UNUSED_VARIABLE(type);
     UNUSED_VARIABLE(premultiplyAlpha);
     UNUSED_VARIABLE(flipY);

     notImplemented();
     completionHandler(false);
 #endif
 }

 void RemoteGraphicsContextGL::simulateEventForTesting(WebCore::GraphicsContextGL::SimulatedEventForTesting event)
 {
     assertIsCurrent(m_streamThread);
     // FIXME: only run this in testing mode. https://bugs.webkit.org/show_bug.cgi?id=222544
     if (event == WebCore::GraphicsContextGL::SimulatedEventForTesting::Timeout) {
         // Simulate the timeout by just discarding the context. The subsequent messages act like
         // unauthorized or old messages from Web process, they are skipped.
         callOnMainRunLoop([gpuConnectionToWebProcess = m_gpuConnectionToWebProcess, identifier = m_graphicsContextGLIdentifier]() {
             if (auto connectionToWeb = gpuConnectionToWebProcess.get())
                 connectionToWeb->releaseGraphicsContextGLForTesting(identifier);
         });
         return;
     }
     if (event == WebCore::GraphicsContextGL::SimulatedEventForTesting::ContextChange) {
 #if PLATFORM(MAC)
         callOnMainRunLoop([weakConnection = m_gpuConnectionToWebProcess]() {
             if (auto connection = weakConnection.get())
                 connection->dispatchDisplayWasReconfiguredForTesting();
         });
 #endif
         return;
     }
     m_context->simulateEventForTesting(event);
 }

 } // namespace WebKit

 #endif
	/*
	* Copyright (C) 2020-2021 Apple Inc. All rights reserved.
	*
	* Redistribution and use in source and binary forms, with or without
	* modification, are permitted provided that the following conditions
	* are met:
	* 1. Redistributions of source code must retain the above copyright
	* notice, this list of conditions and the following disclaimer.
	* 2. Redistributions in binary form must reproduce the above copyright
	* notice, this list of conditions and the following disclaimer in the
	* documentation and/or other materials provided with the distribution.
	*
	* THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS''
	* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
	* THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
	* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS
	* BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
	* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
	* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
	* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
	* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
	* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
	* THE POSSIBILITY OF SUCH DAMAGE.
	*/

	#include "config.h"
	#include "RemoteGraphicsContextGL.h"

	#if ENABLE(GPU_PROCESS) && ENABLE(WEBGL)

	#include "GPUConnectionToWebProcess.h"
	#include "QualifiedRenderingResourceIdentifier.h"
	#include "RemoteGraphicsContextGLMessages.h"
	#include "RemoteGraphicsContextGLProxyMessages.h"
	#include "StreamConnectionWorkQueue.h"
	#include <WebCore/GraphicsContextGLOpenGL.h>
	#include <WebCore/NotImplemented.h>
	#include <wtf/MainThread.h>
	#include <wtf/NeverDestroyed.h>

	#if USE(AVFOUNDATION)
	#include <WebCore/GraphicsContextGLCV.h>
	#endif

	namespace WebKit {

	using namespace WebCore;

	// Currently we have one global WebGL processing instance.
	IPC::StreamConnectionWorkQueue& remoteGraphicsContextGLStreamWorkQueue()
	{
	static NeverDestroyed<IPC::StreamConnectionWorkQueue> instance("RemoteGraphicsContextGL work queue");
	return instance.get();
	}

	#if !PLATFORM(COCOA) && !PLATFORM(WIN)
	Ref<RemoteGraphicsContextGL> RemoteGraphicsContextGL::create(GPUConnectionToWebProcess& gpuConnectionToWebProcess, GraphicsContextGLAttributes&& attributes, GraphicsContextGLIdentifier graphicsContextGLIdentifier, RemoteRenderingBackend& renderingBackend, IPC::StreamConnectionBuffer&& stream)
	{
	ASSERT_NOT_REACHED();
	auto instance = adoptRef(*new RemoteGraphicsContextGL(gpuConnectionToWebProcess, graphicsContextGLIdentifier, renderingBackend, WTFMove(stream)));
	instance->initialize(WTFMove(attributes));
	return instance;
	}
	#endif

	RemoteGraphicsContextGL::RemoteGraphicsContextGL(GPUConnectionToWebProcess& gpuConnectionToWebProcess, GraphicsContextGLIdentifier graphicsContextGLIdentifier, RemoteRenderingBackend& renderingBackend, IPC::StreamConnectionBuffer&& stream)
	: m_gpuConnectionToWebProcess(gpuConnectionToWebProcess)
	, m_streamConnection(IPC::StreamServerConnection::create(gpuConnectionToWebProcess.connection(), WTFMove(stream), remoteGraphicsContextGLStreamWorkQueue()))
	, m_graphicsContextGLIdentifier(graphicsContextGLIdentifier)
	, m_renderingBackend(renderingBackend)
	, m_renderingResourcesRequest(ScopedWebGLRenderingResourcesRequest::acquire())
	, m_webProcessIdentifier(gpuConnectionToWebProcess.webProcessIdentifier())
	{
	assertIsMainRunLoop();
	}

	RemoteGraphicsContextGL::~RemoteGraphicsContextGL()
	{
	ASSERT(!m_streamConnection);
	ASSERT(!m_context);
	// Might be destroyed on main thread or stream processing thread.
	m_streamThread.reset();
	}

	void RemoteGraphicsContextGL::initialize(GraphicsContextGLAttributes&& attributes)
	{
	assertIsMainRunLoop();
	remoteGraphicsContextGLStreamWorkQueue().dispatch([attributes = WTFMove(attributes), protectedThis = Ref { *this }]() mutable {
	protectedThis->workQueueInitialize(WTFMove(attributes));
	});
	m_streamConnection->startReceivingMessages(*this, Messages::RemoteGraphicsContextGL::messageReceiverName(), m_graphicsContextGLIdentifier.toUInt64());
	}

	void RemoteGraphicsContextGL::stopListeningForIPC(Ref<RemoteGraphicsContextGL>&& refFromConnection)
	{
	assertIsMainRunLoop();
	m_streamConnection->stopReceivingMessages(Messages::RemoteGraphicsContextGL::messageReceiverName(), m_graphicsContextGLIdentifier.toUInt64());
	remoteGraphicsContextGLStreamWorkQueue().dispatch([protectedThis = WTFMove(refFromConnection)]() {
	protectedThis->workQueueUninitialize();
	protectedThis->m_renderingResourcesRequest = { };
	});
	}

	#if PLATFORM(MAC)
	void RemoteGraphicsContextGL::displayWasReconfigured()
	{
	assertIsMainRunLoop();
	remoteGraphicsContextGLStreamWorkQueue().dispatch([protectedThis = Ref { *this }]() {
	assertIsCurrent(protectedThis->m_streamThread);
	protectedThis->m_context->displayWasReconfigured();
	});
	}
	#endif

	void RemoteGraphicsContextGL::workQueueInitialize(WebCore::GraphicsContextGLAttributes&& attributes)
	{
	m_streamThread.reset();
	assertIsCurrent(m_streamThread);
	platformWorkQueueInitialize(WTFMove(attributes));
	if (m_context) {
	m_context->addClient(*this);
	String extensions = m_context->getString(GraphicsContextGL::EXTENSIONS);
	String requestableExtensions = m_context->getString(ExtensionsGL::REQUESTABLE_EXTENSIONS_ANGLE);
	send(Messages::RemoteGraphicsContextGLProxy::WasCreated(true, remoteGraphicsContextGLStreamWorkQueue().wakeUpSemaphore(), extensions, requestableExtensions));
	} else
	send(Messages::RemoteGraphicsContextGLProxy::WasCreated(false, IPC::Semaphore { }, "", ""));
	}

	void RemoteGraphicsContextGL::workQueueUninitialize()
	{
	assertIsCurrent(m_streamThread);
	m_context = nullptr;
	m_streamConnection = nullptr;
	}

	void RemoteGraphicsContextGL::didComposite()
	{
	assertIsCurrent(m_streamThread);
	}

	void RemoteGraphicsContextGL::forceContextLost()
	{
	assertIsCurrent(m_streamThread);
	send(Messages::RemoteGraphicsContextGLProxy::WasLost());
	}

	void RemoteGraphicsContextGL::recycleContext()
	{
	ASSERT_NOT_REACHED();
	}

	void RemoteGraphicsContextGL::dispatchContextChangedNotification()
	{
	assertIsCurrent(m_streamThread);
	send(Messages::RemoteGraphicsContextGLProxy::WasChanged());
	}

	void RemoteGraphicsContextGL::reshape(int32_t width, int32_t height)
	{
	assertIsCurrent(m_streamThread);
	if (width && height)
	m_context->reshape(width, height);
	else
	forceContextLost();
	}

	#if !PLATFORM(COCOA) && !PLATFORM(WIN)
	void RemoteGraphicsContextGL::prepareForDisplay(CompletionHandler<void()>&& completionHandler)
	{
	assertIsCurrent(m_streamThread);
	notImplemented();
	completionHandler();
	}
	#endif

	void RemoteGraphicsContextGL::synthesizeGLError(uint32_t error)
	{
	assertIsCurrent(m_streamThread);
	m_context->synthesizeGLError(static_cast<GCGLenum>(error));
	}

	void RemoteGraphicsContextGL::getError(CompletionHandler<void(uint32_t)>&& completionHandler)
	{
	assertIsCurrent(m_streamThread);
	completionHandler(static_cast<uint32_t>(m_context->getError()));
	}

	void RemoteGraphicsContextGL::ensureExtensionEnabled(String&& extension)
	{
	assertIsCurrent(m_streamThread);
	m_context->getExtensions().ensureEnabled(extension);
	}

	void RemoteGraphicsContextGL::notifyMarkContextChanged()
	{
	assertIsCurrent(m_streamThread);
	m_context->markContextChanged();
	}

	void RemoteGraphicsContextGL::paintRenderingResultsToCanvas(WebCore::RenderingResourceIdentifier imageBuffer, CompletionHandler<void()>&& completionHandler)
	{
	// Immediately turn the RenderingResourceIdentifier (which is error-prone) to a QualifiedRenderingResourceIdentifier,
	// and use a helper function to make sure that don't accidentally use the RenderingResourceIdentifier (because the helper function can't see it).
	paintRenderingResultsToCanvasWithQualifiedIdentifier({ imageBuffer, m_webProcessIdentifier }, WTFMove(completionHandler));
	}

	void RemoteGraphicsContextGL::paintRenderingResultsToCanvasWithQualifiedIdentifier(QualifiedRenderingResourceIdentifier imageBuffer, CompletionHandler<void()>&& completionHandler)
	{
	assertIsCurrent(m_streamThread);
	paintPixelBufferToImageBuffer(m_context->readRenderingResultsForPainting(), imageBuffer, WTFMove(completionHandler));
	}

	void RemoteGraphicsContextGL::paintCompositedResultsToCanvas(WebCore::RenderingResourceIdentifier imageBuffer, CompletionHandler<void()>&& completionHandler)
	{
	// Immediately turn the RenderingResourceIdentifier (which is error-prone) to a QualifiedRenderingResourceIdentifier,
	// and use a helper function to make sure that don't accidentally use the RenderingResourceIdentifier (because the helper function can't see it).
	paintCompositedResultsToCanvasWithQualifiedIdentifier({ imageBuffer, m_webProcessIdentifier }, WTFMove(completionHandler));
	}

	void RemoteGraphicsContextGL::paintCompositedResultsToCanvasWithQualifiedIdentifier(QualifiedRenderingResourceIdentifier imageBuffer, CompletionHandler<void()>&& completionHandler)
	{
	assertIsCurrent(m_streamThread);
	paintPixelBufferToImageBuffer(m_context->readCompositedResultsForPainting(), imageBuffer, WTFMove(completionHandler));
	}

	void RemoteGraphicsContextGL::paintPixelBufferToImageBuffer(std::optional<WebCore::PixelBuffer>&& pixelBuffer, QualifiedRenderingResourceIdentifier target, CompletionHandler<void()>&& completionHandler)
	{
	assertIsCurrent(m_streamThread);
	// FIXME: We do not have functioning read/write fences in RemoteRenderingBackend. Thus this is synchronous,
	// as are the messages that call these.
	Lock lock;
	Condition conditionVariable;
	bool isFinished = false;
	m_renderingBackend->dispatch([&, contextAttributes = m_context->contextAttributes()]() mutable {
	if (auto imageBuffer = m_renderingBackend->remoteResourceCache().cachedImageBuffer(target)) {
	// Here we do not try to play back pending commands for imageBuffer. Currently this call is only made for empty
	// image buffers and there's no good way to add display lists.
	if (pixelBuffer)
	GraphicsContextGLOpenGL::paintToCanvas(contextAttributes, WTFMove(*pixelBuffer), imageBuffer->backendSize(), imageBuffer->context());
	else
	imageBuffer->context().clearRect({ IntPoint(), imageBuffer->backendSize() });
	// Unfortunately "flush" implementation in RemoteRenderingBackend overloads ordering and effects.
	imageBuffer->flushContext();
	}
	Locker locker { lock };
	isFinished = true;
	conditionVariable.notifyOne();
	});
	Locker locker { lock };
	conditionVariable.wait(lock, [&] {
	return isFinished;
	});
	completionHandler();
	}

	void RemoteGraphicsContextGL::copyTextureFromMedia(WebCore::MediaPlayerIdentifier mediaPlayerIdentifier, uint32_t texture, uint32_t target, int32_t level, uint32_t internalFormat, uint32_t format, uint32_t type, bool premultiplyAlpha, bool flipY, CompletionHandler<void(bool)>&& completionHandler)
	{
	assertIsCurrent(m_streamThread);
	#if USE(AVFOUNDATION)
	UNUSED_VARIABLE(premultiplyAlpha);
	ASSERT_UNUSED(target, target == GraphicsContextGL::TEXTURE_2D);

	RetainPtr<CVPixelBufferRef> pixelBuffer;
	auto getPixelBuffer = [&] {
	if (!m_gpuConnectionToWebProcess)
	return;

	if (auto mediaPlayer = m_gpuConnectionToWebProcess->remoteMediaPlayerManagerProxy().mediaPlayer(mediaPlayerIdentifier))
	pixelBuffer = mediaPlayer->pixelBufferForCurrentTime();
	};

	callOnMainRunLoopAndWait(WTFMove(getPixelBuffer));

	if (!pixelBuffer) {
	completionHandler(false);
	return;
	}

	auto contextCV = m_context->asCV();
	if (!contextCV) {
	completionHandler(false);
	return;
	}

	completionHandler(contextCV->copyPixelBufferToTexture(pixelBuffer.get(), texture, level, internalFormat, format, type, GraphicsContextGL::FlipY(flipY)));
	#else
	UNUSED_VARIABLE(mediaPlayerIdentifier);
	UNUSED_VARIABLE(texture);
	UNUSED_VARIABLE(target);
	UNUSED_VARIABLE(level);
	UNUSED_VARIABLE(internalFormat);
	UNUSED_VARIABLE(format);
	UNUSED_VARIABLE(type);
	UNUSED_VARIABLE(premultiplyAlpha);
	UNUSED_VARIABLE(flipY);

	notImplemented();
	completionHandler(false);
	#endif
	}

	void RemoteGraphicsContextGL::simulateEventForTesting(WebCore::GraphicsContextGL::SimulatedEventForTesting event)
	{
	assertIsCurrent(m_streamThread);
	// FIXME: only run this in testing mode. https://bugs.webkit.org/show_bug.cgi?id=222544
	if (event == WebCore::GraphicsContextGL::SimulatedEventForTesting::Timeout) {
	// Simulate the timeout by just discarding the context. The subsequent messages act like
	// unauthorized or old messages from Web process, they are skipped.
	callOnMainRunLoop([gpuConnectionToWebProcess = m_gpuConnectionToWebProcess, identifier = m_graphicsContextGLIdentifier]() {
	if (auto connectionToWeb = gpuConnectionToWebProcess.get())
	connectionToWeb->releaseGraphicsContextGLForTesting(identifier);
	});
	return;
	}
	if (event == WebCore::GraphicsContextGL::SimulatedEventForTesting::ContextChange) {
	#if PLATFORM(MAC)
	callOnMainRunLoop([weakConnection = m_gpuConnectionToWebProcess]() {
	if (auto connection = weakConnection.get())
	connection->dispatchDisplayWasReconfiguredForTesting();
	});
	#endif
	return;
	}
	m_context->simulateEventForTesting(event);
	}

	} // namespace WebKit

	#endif