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[WPE][Skia] Enable MSAA when available
https://bugs.webkit.org/show_bug.cgi?id=277800 Reviewed by Carlos Garcia Campos. Enable MSAA on WPE whenever possible. On x86 or x86_64, use eight samples to get an antialiasing result similar to non MSAA. On embedded devices, use four samples instead, as this is a nice compromise between quality and resource usage. On GTK keep it disabled by default. The user can overwrite this default value through the WEBKIT_MSAA_SAMPLE_COUNT env var. Even if MSAA is reported as available by GLES, Skia has a lot of internal checks that may disable it, so the best way to check whether we can use it with Skia is trying to create a texture backed SkSurface with a sample count of four and check whether it works. * Source/WebCore/platform/graphics/PlatformDisplay.h: * Source/WebCore/platform/graphics/skia/ImageBufferSkiaAcceleratedBackend.cpp: (WebCore::ImageBufferSkiaAcceleratedBackend::create): (WebCore::flushSurfaceIfNeeded): (WebCore::ImageBufferSkiaAcceleratedBackend::copyNativeImage): (WebCore::ImageBufferSkiaAcceleratedBackend::createNativeImageReference): * Source/WebCore/platform/graphics/skia/PlatformDisplaySkia.cpp: (WebCore::initializeMSAASampleCount): (WebCore::SkiaGLContext::sampleCount): (WebCore::SkiaGLContext::SkiaGLContext): (WebCore::PlatformDisplay::msaaSampleCount): * Source/WebCore/platform/graphics/skia/SkiaAcceleratedBufferPool.cpp: (WebCore::SkiaAcceleratedBufferPool::createAcceleratedBuffer): Canonical link: https://commits.webkit.org/282223@main
1 parent 5a46936 commit 1bd3d2f

4 files changed

Lines changed: 76 additions & 2 deletions

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‎Source/WebCore/platform/graphics/PlatformDisplay.h‎

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@@ -145,6 +145,7 @@ class PlatformDisplay {
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#if USE(SKIA)
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GLContext* skiaGLContext();
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GrDirectContext* skiaGrContext();
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unsigned msaaSampleCount();
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#endif
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#if USE(ATSPI)

‎Source/WebCore/platform/graphics/skia/ImageBufferSkiaAcceleratedBackend.cpp‎

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@@ -74,7 +74,7 @@ std::unique_ptr<ImageBufferSkiaAcceleratedBackend> ImageBufferSkiaAcceleratedBac
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RELEASE_ASSERT(grContext);
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auto imageInfo = SkImageInfo::Make(backendSize.width(), backendSize.height(), kRGBA_8888_SkColorType, kPremul_SkAlphaType, parameters.colorSpace.platformColorSpace());
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SkSurfaceProps properties = { 0, FontRenderOptions::singleton().subpixelOrder() };
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auto surface = SkSurfaces::RenderTarget(grContext, skgpu::Budgeted::kNo, imageInfo, 0, kTopLeft_GrSurfaceOrigin, &properties);
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auto surface = SkSurfaces::RenderTarget(grContext, skgpu::Budgeted::kNo, imageInfo, PlatformDisplay::sharedDisplay().msaaSampleCount(), kTopLeft_GrSurfaceOrigin, &properties);
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if (!surface || !surface->getCanvas())
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return nullptr;
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@@ -107,14 +107,30 @@ ImageBufferSkiaAcceleratedBackend::~ImageBufferSkiaAcceleratedBackend()
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#endif
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}
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void flushSurfaceIfNeeded(SkSurface* surface)
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{
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// If we're using MSAA, we need to flush the surface before calling makeImageSnapshot(),
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// because that call doesn't force the MSAA resolution, which can produce outdated results
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// in the resulting SkImage.
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auto& display = PlatformDisplay::sharedDisplay();
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if (display.msaaSampleCount() > 0) {
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auto* glContext = display.skiaGLContext();
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if (!glContext || !glContext->makeContextCurrent())
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return;
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display.skiaGrContext()->flush(surface);
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}
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}
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RefPtr<NativeImage> ImageBufferSkiaAcceleratedBackend::copyNativeImage()
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{
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// FIXME: do we have to do a explicit copy here?
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flushSurfaceIfNeeded(m_surface.get());
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return NativeImage::create(m_surface->makeImageSnapshot());
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}
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RefPtr<NativeImage> ImageBufferSkiaAcceleratedBackend::createNativeImageReference()
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{
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flushSurfaceIfNeeded(m_surface.get());
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return NativeImage::create(m_surface->makeImageSnapshot());
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}
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‎Source/WebCore/platform/graphics/skia/PlatformDisplaySkia.cpp‎

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@@ -27,7 +27,9 @@
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#include "PlatformDisplay.h"
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#if USE(SKIA)
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#include "FontRenderOptions.h"
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#include "GLContext.h"
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#include <skia/core/SkColorSpace.h>
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#include <skia/gpu/GrBackendSurface.h>
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#include <skia/gpu/ganesh/gl/GrGLBackendSurface.h>
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#include <skia/gpu/ganesh/gl/GrGLDirectContext.h>
@@ -36,6 +38,7 @@
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#include <wtf/NeverDestroyed.h>
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#include <wtf/RunLoop.h>
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#include <wtf/ThreadSafeWeakPtr.h>
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#include <wtf/text/StringToIntegerConversion.h>
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#include <wtf/threads/BinarySemaphore.h>
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IGNORE_CLANG_WARNINGS_BEGIN("cast-align")
@@ -50,6 +53,21 @@ IGNORE_CLANG_WARNINGS_END
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namespace WebCore {
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#if PLATFORM(WPE)
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#if CPU(X86) || CPU(X86_64)
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// On x86 ot x86_64 we need at least 8 samples for the antialiasing result to be similar
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// to non MSAA.
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static const unsigned s_defaultSampleCount = 8;
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#else
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// On embedded, we sacrifice a bit of antialiasing quality to save memory and improve
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// performance.
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static const unsigned s_defaultSampleCount = 4;
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#endif
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#else
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// Disable MSAA by default.
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static const unsigned s_defaultSampleCount = 0;
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#endif
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#if !(PLATFORM(PLAYSTATION) && USE(COORDINATED_GRAPHICS))
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static sk_sp<const GrGLInterface> skiaGLInterface()
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{
@@ -66,6 +84,32 @@ static sk_sp<const GrGLInterface> skiaGLInterface()
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static thread_local RefPtr<SkiaGLContext> s_skiaGLContext;
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unsigned initializeMSAASampleCount(GrDirectContext* grContext)
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{
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static std::once_flag onceFlag;
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static int sampleCount = s_defaultSampleCount;
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std::call_once(onceFlag, [grContext] {
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// Let the user override the default sample count if they want to.
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String envString = String::fromLatin1(getenv("WEBKIT_MSAA_SAMPLE_COUNT"));
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if (!envString.isEmpty())
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sampleCount = parseInteger<unsigned>(envString).value_or(0);
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// Skia checks internally whether MSAA is supported, but also disables it for several platforms where it
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// knows there are bugs. The only way to know whether our sample count will work is trying to create a
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// surface with that value and check whether it works.
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auto imageInfo = SkImageInfo::Make(512, 512, kRGBA_8888_SkColorType, kPremul_SkAlphaType, SkColorSpace::MakeSRGB());
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SkSurfaceProps properties = { 0, FontRenderOptions::singleton().subpixelOrder() };
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auto surface = SkSurfaces::RenderTarget(grContext, skgpu::Budgeted::kNo, imageInfo, sampleCount, kTopLeft_GrSurfaceOrigin, &properties);
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// If the creation of the surface failed, disable MSAA.
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if (!surface)
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sampleCount = 0;
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});
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return sampleCount;
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}
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class SkiaGLContext : public ThreadSafeRefCountedAndCanMakeThreadSafeWeakPtr<SkiaGLContext> {
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public:
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static Ref<SkiaGLContext> create(PlatformDisplay& display)
@@ -102,6 +146,11 @@ class SkiaGLContext : public ThreadSafeRefCountedAndCanMakeThreadSafeWeakPtr<Ski
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return m_skiaGrContext.get();
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}
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unsigned sampleCount()
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{
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return m_sampleCount;
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}
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private:
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explicit SkiaGLContext(PlatformDisplay& display)
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: m_runLoop(&RunLoop::current())
@@ -115,6 +164,8 @@ class SkiaGLContext : public ThreadSafeRefCountedAndCanMakeThreadSafeWeakPtr<Ski
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m_skiaGLContext = WTFMove(glContext);
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m_skiaGrContext = WTFMove(grContext);
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}
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m_sampleCount = initializeMSAASampleCount(m_skiaGrContext.get());
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}
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void invalidateOnCurrentThread()
@@ -128,6 +179,7 @@ class SkiaGLContext : public ThreadSafeRefCountedAndCanMakeThreadSafeWeakPtr<Ski
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std::unique_ptr<GLContext> m_skiaGLContext WTF_GUARDED_BY_LOCK(m_lock);
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sk_sp<GrDirectContext> m_skiaGrContext WTF_GUARDED_BY_LOCK(m_lock);
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mutable Lock m_lock;
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unsigned m_sampleCount { 0 };
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};
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#endif
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@@ -152,6 +204,11 @@ GrDirectContext* PlatformDisplay::skiaGrContext()
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return s_skiaGLContext->skiaGrContext();
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}
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unsigned PlatformDisplay::msaaSampleCount()
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{
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return s_skiaGLContext->sampleCount();
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}
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void PlatformDisplay::invalidateSkiaGLContexts()
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{
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auto contexts = WTFMove(m_skiaGLContexts);

‎Source/WebCore/platform/graphics/skia/SkiaAcceleratedBufferPool.cpp‎

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Original file line numberDiff line numberDiff line change
@@ -73,7 +73,7 @@ RefPtr<Nicosia::Buffer> SkiaAcceleratedBufferPool::createAcceleratedBuffer(const
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RELEASE_ASSERT(grContext);
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auto imageInfo = SkImageInfo::Make(size.width(), size.height(), kRGBA_8888_SkColorType, kPremul_SkAlphaType, SkColorSpace::MakeSRGB());
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SkSurfaceProps properties = { 0, FontRenderOptions::singleton().subpixelOrder() };
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auto surface = SkSurfaces::RenderTarget(grContext, skgpu::Budgeted::kNo, imageInfo, 0, kTopLeft_GrSurfaceOrigin, &properties);
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auto surface = SkSurfaces::RenderTarget(grContext, skgpu::Budgeted::kNo, imageInfo, PlatformDisplay::sharedDisplay().msaaSampleCount(), kTopLeft_GrSurfaceOrigin, &properties);
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if (!surface)
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return nullptr;
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return Nicosia::AcceleratedBuffer::create(WTFMove(surface), supportsAlpha ? Nicosia::Buffer::SupportsAlpha : Nicosia::Buffer::NoFlags);

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