The Tor Browser: gfx/layers/client/TiledContentClient.cpp@6474c204b198 (annotated)

gfx/layers/client/TiledContentClient.cpp@6474c204b198 (annotated)

gfx/layers/client/TiledContentClient.cpp

Wed, 31 Dec 2014 06:09:35 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Wed, 31 Dec 2014 06:09:35 +0100
changeset 0: 6474c204b198
permissions: -rw-r--r--

Cloned upstream origin tor-browser at tor-browser-31.3.0esr-4.5-1-build1
revision ID fc1c9ff7c1b2defdbc039f12214767608f46423f for hacking purpose.

 /* -*- Mode: C++; tab-width: 20; 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/. */
 #include "mozilla/layers/TiledContentClient.h"
 #include <math.h>                       // for ceil, ceilf, floor
 #include "ClientTiledThebesLayer.h"     // for ClientTiledThebesLayer
 #include "GeckoProfiler.h"              // for PROFILER_LABEL
 #include "ClientLayerManager.h"         // for ClientLayerManager
 #include "CompositorChild.h"            // for CompositorChild
 #include "gfxContext.h"                 // for gfxContext, etc
 #include "gfxPlatform.h"                // for gfxPlatform
 #include "gfxPrefs.h"                   // for gfxPrefs
 #include "gfxRect.h"                    // for gfxRect
 #include "mozilla/MathAlgorithms.h"     // for Abs
 #include "mozilla/gfx/Point.h"          // for IntSize
 #include "mozilla/gfx/Rect.h"           // for Rect
 #include "mozilla/layers/CompositableForwarder.h"
 #include "mozilla/layers/ShadowLayers.h"  // for ShadowLayerForwarder
 #include "TextureClientPool.h"
 #include "nsDebug.h"                    // for NS_ASSERTION
 #include "nsISupportsImpl.h"            // for gfxContext::AddRef, etc
 #include "nsSize.h"                     // for nsIntSize
 #include "gfxReusableSharedImageSurfaceWrapper.h"
 #include "nsMathUtils.h"               // for NS_roundf
 #include "gfx2DGlue.h"
 // This is the minimum area that we deem reasonable to copy from the front buffer to the
 // back buffer on tile updates. If the valid region is smaller than this, we just
 // redraw it and save on the copy (and requisite surface-locking involved).
 #define MINIMUM_TILE_COPY_AREA (1.f/16.f)
 #ifdef GFX_TILEDLAYER_DEBUG_OVERLAY
 #include "cairo.h"
 #include <sstream>
 using mozilla::layers::Layer;
 static void DrawDebugOverlay(mozilla::gfx::DrawTarget* dt, int x, int y, int width, int height)
 {
   gfxContext c(dt);
   // Draw border
   c.NewPath();
   c.SetDeviceColor(gfxRGBA(0.0, 0.0, 0.0, 1.0));
   c.Rectangle(gfxRect(0, 0, width, height));
   c.Stroke();
   // Build tile description
   std::stringstream ss;
   ss << x << ", " << y;
   // Draw text using cairo toy text API
   cairo_t* cr = c.GetCairo();
   cairo_set_font_size(cr, 25);
   cairo_text_extents_t extents;
   cairo_text_extents(cr, ss.str().c_str(), &extents);
   int textWidth = extents.width + 6;
   c.NewPath();
   c.SetDeviceColor(gfxRGBA(0.0, 0.0, 0.0, 1.0));
   c.Rectangle(gfxRect(gfxPoint(2,2),gfxSize(textWidth, 30)));
   c.Fill();
   c.NewPath();
   c.SetDeviceColor(gfxRGBA(1.0, 0.0, 0.0, 1.0));
   c.Rectangle(gfxRect(gfxPoint(2,2),gfxSize(textWidth, 30)));
   c.Stroke();
   c.NewPath();
   cairo_move_to(cr, 4, 28);
   cairo_show_text(cr, ss.str().c_str());
 }
 #endif
 namespace mozilla {
 using namespace gfx;
 namespace layers {
 TiledContentClient::TiledContentClient(ClientTiledThebesLayer* aThebesLayer,
                                        ClientLayerManager* aManager)
   : CompositableClient(aManager->AsShadowForwarder())
 {
   MOZ_COUNT_CTOR(TiledContentClient);
   mTiledBuffer = ClientTiledLayerBuffer(aThebesLayer, this, aManager,
                                         &mSharedFrameMetricsHelper);
   mLowPrecisionTiledBuffer = ClientTiledLayerBuffer(aThebesLayer, this, aManager,
                                                     &mSharedFrameMetricsHelper);
   mLowPrecisionTiledBuffer.SetResolution(gfxPrefs::LowPrecisionResolution()/1000.f);
 }
 void
 TiledContentClient::ClearCachedResources()
 {
   mTiledBuffer.DiscardBackBuffers();
   mLowPrecisionTiledBuffer.DiscardBackBuffers();
 }
 void
 TiledContentClient::UseTiledLayerBuffer(TiledBufferType aType)
 {
   ClientTiledLayerBuffer* buffer = aType == LOW_PRECISION_TILED_BUFFER
     ? &mLowPrecisionTiledBuffer
     : &mTiledBuffer;
   // Take a ReadLock on behalf of the TiledContentHost. This
   // reference will be adopted when the descriptor is opened in
   // TiledLayerBufferComposite.
   buffer->ReadLock();
   mForwarder->UseTiledLayerBuffer(this, buffer->GetSurfaceDescriptorTiles());
   buffer->ClearPaintedRegion();
 }
 SharedFrameMetricsHelper::SharedFrameMetricsHelper()
   : mLastProgressiveUpdateWasLowPrecision(false)
   , mProgressiveUpdateWasInDanger(false)
 {
   MOZ_COUNT_CTOR(SharedFrameMetricsHelper);
 }
 SharedFrameMetricsHelper::~SharedFrameMetricsHelper()
 {
   MOZ_COUNT_DTOR(SharedFrameMetricsHelper);
 }
 static inline bool
 FuzzyEquals(float a, float b) {
   return (fabsf(a - b) < 1e-6);
 }
 bool
 SharedFrameMetricsHelper::UpdateFromCompositorFrameMetrics(
     ContainerLayer* aLayer,
     bool aHasPendingNewThebesContent,
     bool aLowPrecision,
     ParentLayerRect& aCompositionBounds,
     CSSToParentLayerScale& aZoom)
 {
   MOZ_ASSERT(aLayer);
   CompositorChild* compositor = CompositorChild::Get();
   if (!compositor) {
     FindFallbackContentFrameMetrics(aLayer, aCompositionBounds, aZoom);
     return false;
   }
   const FrameMetrics& contentMetrics = aLayer->GetFrameMetrics();
   FrameMetrics compositorMetrics;
   if (!compositor->LookupCompositorFrameMetrics(contentMetrics.GetScrollId(),
                                                 compositorMetrics)) {
     FindFallbackContentFrameMetrics(aLayer, aCompositionBounds, aZoom);
     return false;
   }
   aCompositionBounds = ParentLayerRect(compositorMetrics.mCompositionBounds);
   aZoom = compositorMetrics.GetZoomToParent();
   // Reset the checkerboard risk flag when switching to low precision
   // rendering.
   if (aLowPrecision && !mLastProgressiveUpdateWasLowPrecision) {
     // Skip low precision rendering until we're at risk of checkerboarding.
     if (!mProgressiveUpdateWasInDanger) {
       return true;
     }
     mProgressiveUpdateWasInDanger = false;
   }
   mLastProgressiveUpdateWasLowPrecision = aLowPrecision;
   // Always abort updates if the resolution has changed. There's no use
   // in drawing at the incorrect resolution.
   if (!FuzzyEquals(compositorMetrics.GetZoom().scale, contentMetrics.GetZoom().scale)) {
     return true;
   }
   // Never abort drawing if we can't be sure we've sent a more recent
   // display-port. If we abort updating when we shouldn't, we can end up
   // with blank regions on the screen and we open up the risk of entering
   // an endless updating cycle.
   if (fabsf(contentMetrics.GetScrollOffset().x - compositorMetrics.GetScrollOffset().x) <= 2 &&
       fabsf(contentMetrics.GetScrollOffset().y - compositorMetrics.GetScrollOffset().y) <= 2 &&
       fabsf(contentMetrics.mDisplayPort.x - compositorMetrics.mDisplayPort.x) <= 2 &&
       fabsf(contentMetrics.mDisplayPort.y - compositorMetrics.mDisplayPort.y) <= 2 &&
       fabsf(contentMetrics.mDisplayPort.width - compositorMetrics.mDisplayPort.width) <= 2 &&
       fabsf(contentMetrics.mDisplayPort.height - compositorMetrics.mDisplayPort.height)) {
     return false;
   }
   // When not a low precision pass and the page is in danger of checker boarding
   // abort update.
   if (!aLowPrecision && !mProgressiveUpdateWasInDanger) {
     if (AboutToCheckerboard(contentMetrics, compositorMetrics)) {
       mProgressiveUpdateWasInDanger = true;
       return true;
     }
   }
   // Abort drawing stale low-precision content if there's a more recent
   // display-port in the pipeline.
   if (aLowPrecision && !aHasPendingNewThebesContent) {
     return true;
   }
   return false;
 }
 void
 SharedFrameMetricsHelper::FindFallbackContentFrameMetrics(ContainerLayer* aLayer,
                                                           ParentLayerRect& aCompositionBounds,
                                                           CSSToParentLayerScale& aZoom) {
   if (!aLayer) {
     return;
   }
   ContainerLayer* layer = aLayer;
   const FrameMetrics* contentMetrics = &(layer->GetFrameMetrics());
   // Walk up the layer tree until a valid composition bounds is found
   while (layer && contentMetrics->mCompositionBounds.IsEmpty()) {
     layer = layer->GetParent();
     contentMetrics = layer ? &(layer->GetFrameMetrics()) : contentMetrics;
   }
   MOZ_ASSERT(!contentMetrics->mCompositionBounds.IsEmpty());
   aCompositionBounds = ParentLayerRect(contentMetrics->mCompositionBounds);
   aZoom = contentMetrics->GetZoomToParent();  // TODO(botond): double-check this
   return;
 }
 bool
 SharedFrameMetricsHelper::AboutToCheckerboard(const FrameMetrics& aContentMetrics,
                                               const FrameMetrics& aCompositorMetrics)
 {
   return !aContentMetrics.mDisplayPort.Contains(aCompositorMetrics.CalculateCompositedRectInCssPixels() - aCompositorMetrics.GetScrollOffset());
 }
 ClientTiledLayerBuffer::ClientTiledLayerBuffer(ClientTiledThebesLayer* aThebesLayer,
                                              CompositableClient* aCompositableClient,
                                              ClientLayerManager* aManager,
                                              SharedFrameMetricsHelper* aHelper)
   : mThebesLayer(aThebesLayer)
   , mCompositableClient(aCompositableClient)
   , mManager(aManager)
   , mLastPaintOpaque(false)
   , mSharedFrameMetricsHelper(aHelper)
 {
 }
 bool
 ClientTiledLayerBuffer::HasFormatChanged() const
 {
   return mThebesLayer->CanUseOpaqueSurface() != mLastPaintOpaque;
 }
 gfxContentType
 ClientTiledLayerBuffer::GetContentType() const
 {
   if (mThebesLayer->CanUseOpaqueSurface()) {
     return gfxContentType::COLOR;
   } else {
     return gfxContentType::COLOR_ALPHA;
   }
 }
 gfxMemorySharedReadLock::gfxMemorySharedReadLock()
   : mReadCount(1)
 {
   MOZ_COUNT_CTOR(gfxMemorySharedReadLock);
 }
 gfxMemorySharedReadLock::~gfxMemorySharedReadLock()
 {
   MOZ_COUNT_DTOR(gfxMemorySharedReadLock);
 }
 int32_t
 gfxMemorySharedReadLock::ReadLock()
 {
   NS_ASSERT_OWNINGTHREAD(gfxMemorySharedReadLock);
   return PR_ATOMIC_INCREMENT(&mReadCount);
 }
 int32_t
 gfxMemorySharedReadLock::ReadUnlock()
 {
   int32_t readCount = PR_ATOMIC_DECREMENT(&mReadCount);
   NS_ASSERTION(readCount >= 0, "ReadUnlock called without ReadLock.");
   return readCount;
 }
 int32_t
 gfxMemorySharedReadLock::GetReadCount()
 {
   NS_ASSERT_OWNINGTHREAD(gfxMemorySharedReadLock);
   return mReadCount;
 }
 gfxShmSharedReadLock::gfxShmSharedReadLock(ISurfaceAllocator* aAllocator)
   : mAllocator(aAllocator)
   , mAllocSuccess(false)
 {
   MOZ_COUNT_CTOR(gfxShmSharedReadLock);
   MOZ_ASSERT(mAllocator);
   if (mAllocator) {
 #define MOZ_ALIGN_WORD(x) (((x) + 3) & ~3)
     if (mAllocator->AllocShmemSection(MOZ_ALIGN_WORD(sizeof(ShmReadLockInfo)), &mShmemSection)) {
       ShmReadLockInfo* info = GetShmReadLockInfoPtr();
       info->readCount = 1;
       mAllocSuccess = true;
     }
   }
 }
 gfxShmSharedReadLock::~gfxShmSharedReadLock()
 {
   MOZ_COUNT_DTOR(gfxShmSharedReadLock);
 }
 int32_t
 gfxShmSharedReadLock::ReadLock() {
   NS_ASSERT_OWNINGTHREAD(gfxShmSharedReadLock);
   if (!mAllocSuccess) {
     return 0;
   }
   ShmReadLockInfo* info = GetShmReadLockInfoPtr();
   return PR_ATOMIC_INCREMENT(&info->readCount);
 }
 int32_t
 gfxShmSharedReadLock::ReadUnlock() {
   if (!mAllocSuccess) {
     return 0;
   }
   ShmReadLockInfo* info = GetShmReadLockInfoPtr();
   int32_t readCount = PR_ATOMIC_DECREMENT(&info->readCount);
   NS_ASSERTION(readCount >= 0, "ReadUnlock called without a ReadLock.");
   if (readCount <= 0) {
     mAllocator->FreeShmemSection(mShmemSection);
   }
   return readCount;
 }
 int32_t
 gfxShmSharedReadLock::GetReadCount() {
   NS_ASSERT_OWNINGTHREAD(gfxShmSharedReadLock);
   if (!mAllocSuccess) {
     return 0;
   }
   ShmReadLockInfo* info = GetShmReadLockInfoPtr();
   return info->readCount;
 }
 // Placeholder
 TileClient::TileClient()
   : mBackBuffer(nullptr)
   , mFrontBuffer(nullptr)
   , mBackLock(nullptr)
   , mFrontLock(nullptr)
 {
 }
 TileClient::TileClient(const TileClient& o)
 {
   mBackBuffer = o.mBackBuffer;
   mFrontBuffer = o.mFrontBuffer;
   mBackLock = o.mBackLock;
   mFrontLock = o.mFrontLock;
 #ifdef GFX_TILEDLAYER_DEBUG_OVERLAY
   mLastUpdate = o.mLastUpdate;
 #endif
   mManager = o.mManager;
   mInvalidFront = o.mInvalidFront;
   mInvalidBack = o.mInvalidBack;
 }
 TileClient&
 TileClient::operator=(const TileClient& o)
 {
   if (this == &o) return *this;
   mBackBuffer = o.mBackBuffer;
   mFrontBuffer = o.mFrontBuffer;
   mBackLock = o.mBackLock;
   mFrontLock = o.mFrontLock;
 #ifdef GFX_TILEDLAYER_DEBUG_OVERLAY
   mLastUpdate = o.mLastUpdate;
 #endif
   mManager = o.mManager;
   mInvalidFront = o.mInvalidFront;
   mInvalidBack = o.mInvalidBack;
   return *this;
 }
 void
 TileClient::Flip()
 {
   RefPtr<TextureClient> frontBuffer = mFrontBuffer;
   mFrontBuffer = mBackBuffer;
   mBackBuffer = frontBuffer;
   RefPtr<gfxSharedReadLock> frontLock = mFrontLock;
   mFrontLock = mBackLock;
   mBackLock = frontLock;
   nsIntRegion invalidFront = mInvalidFront;
   mInvalidFront = mInvalidBack;
   mInvalidBack = invalidFront;
 }
 void
 TileClient::ValidateBackBufferFromFront(const nsIntRegion& aDirtyRegion,
                                         bool aCanRerasterizeValidRegion)
 {
   if (mBackBuffer && mFrontBuffer) {
     gfx::IntSize tileSize = mFrontBuffer->GetSize();
     const nsIntRect tileRect = nsIntRect(0, 0, tileSize.width, tileSize.height);
     if (aDirtyRegion.Contains(tileRect)) {
       // The dirty region means that we no longer need the front buffer, so
       // discard it.
       DiscardFrontBuffer();
     } else {
       // Region that needs copying.
       nsIntRegion regionToCopy = mInvalidBack;
       regionToCopy.Sub(regionToCopy, aDirtyRegion);
       if (regionToCopy.IsEmpty() ||
           (aCanRerasterizeValidRegion &&
            regionToCopy.Area() < tileSize.width * tileSize.height * MINIMUM_TILE_COPY_AREA)) {
         // Just redraw it all.
         return;
       }
       if (!mFrontBuffer->Lock(OPEN_READ)) {
         NS_WARNING("Failed to lock the tile's front buffer");
         return;
       }
       TextureClientAutoUnlock autoFront(mFrontBuffer);
       if (!mBackBuffer->Lock(OPEN_WRITE)) {
         NS_WARNING("Failed to lock the tile's back buffer");
         return;
       }
       TextureClientAutoUnlock autoBack(mBackBuffer);
       // Copy the bounding rect of regionToCopy. As tiles are quite small, it
       // is unlikely that we'd save much by copying each individual rect of the
       // region, but we can reevaluate this if it becomes an issue.
       const nsIntRect rectToCopy = regionToCopy.GetBounds();
       gfx::IntRect gfxRectToCopy(rectToCopy.x, rectToCopy.y, rectToCopy.width, rectToCopy.height);
       gfx::IntPoint gfxRectToCopyTopLeft = gfxRectToCopy.TopLeft();
       mFrontBuffer->CopyToTextureClient(mBackBuffer, &gfxRectToCopy, &gfxRectToCopyTopLeft);
       mInvalidBack.SetEmpty();
     }
   }
 }
 void
 TileClient::DiscardFrontBuffer()
 {
   if (mFrontBuffer) {
     MOZ_ASSERT(mFrontLock);
     mManager->GetTexturePool(mFrontBuffer->GetFormat())->ReturnTextureClientDeferred(mFrontBuffer);
     mFrontLock->ReadUnlock();
     mFrontBuffer = nullptr;
     mFrontLock = nullptr;
   }
 }
 void
 TileClient::DiscardBackBuffer()
 {
   if (mBackBuffer) {
     MOZ_ASSERT(mBackLock);
     if (!mBackBuffer->ImplementsLocking() && mBackLock->GetReadCount() > 1) {
       // Our current back-buffer is still locked by the compositor. This can occur
       // when the client is producing faster than the compositor can consume. In
       // this case we just want to drop it and not return it to the pool.
       mManager->GetTexturePool(mBackBuffer->GetFormat())->ReportClientLost();
     } else {
       mManager->GetTexturePool(mBackBuffer->GetFormat())->ReturnTextureClient(mBackBuffer);
     }
     mBackLock->ReadUnlock();
     mBackBuffer = nullptr;
     mBackLock = nullptr;
   }
 }
 TextureClient*
 TileClient::GetBackBuffer(const nsIntRegion& aDirtyRegion, TextureClientPool *aPool, bool *aCreatedTextureClient, bool aCanRerasterizeValidRegion)
 {
   // Try to re-use the front-buffer if possible
   if (mFrontBuffer &&
       mFrontBuffer->HasInternalBuffer() &&
       mFrontLock->GetReadCount() == 1) {
     // If we had a backbuffer we no longer care about it since we'll
     // re-use the front buffer.
     DiscardBackBuffer();
     Flip();
     return mBackBuffer;
   }
   if (!mBackBuffer ||
       mBackLock->GetReadCount() > 1) {
     if (mBackBuffer) {
       // Our current back-buffer is still locked by the compositor. This can occur
       // when the client is producing faster than the compositor can consume. In
       // this case we just want to drop it and not return it to the pool.
       aPool->ReportClientLost();
     }
     mBackBuffer = aPool->GetTextureClient();
     // Create a lock for our newly created back-buffer.
     if (gfxPlatform::GetPlatform()->PreferMemoryOverShmem()) {
       // If our compositor is in the same process, we can save some cycles by not
       // using shared memory.
       mBackLock = new gfxMemorySharedReadLock();
     } else {
       mBackLock = new gfxShmSharedReadLock(mManager->AsShadowForwarder());
     }
     MOZ_ASSERT(mBackLock->IsValid());
     *aCreatedTextureClient = true;
     mInvalidBack = nsIntRect(0, 0, mBackBuffer->GetSize().width, mBackBuffer->GetSize().height);
   }
   ValidateBackBufferFromFront(aDirtyRegion, aCanRerasterizeValidRegion);
   return mBackBuffer;
 }
 TileDescriptor
 TileClient::GetTileDescriptor()
 {
   if (IsPlaceholderTile()) {
     return PlaceholderTileDescriptor();
   }
   MOZ_ASSERT(mFrontLock);
   if (mFrontLock->GetType() == gfxSharedReadLock::TYPE_MEMORY) {
     // AddRef here and Release when receiving on the host side to make sure the
     // reference count doesn't go to zero before the host receives the message.
     // see TiledLayerBufferComposite::TiledLayerBufferComposite
     mFrontLock->AddRef();
   }
   if (mFrontLock->GetType() == gfxSharedReadLock::TYPE_MEMORY) {
     return TexturedTileDescriptor(nullptr, mFrontBuffer->GetIPDLActor(),
                                   TileLock(uintptr_t(mFrontLock.get())));
   } else {
     gfxShmSharedReadLock *lock = static_cast<gfxShmSharedReadLock*>(mFrontLock.get());
     return TexturedTileDescriptor(nullptr, mFrontBuffer->GetIPDLActor(),
                                   TileLock(lock->GetShmemSection()));
   }
 }
 void
 ClientTiledLayerBuffer::ReadUnlock() {
   for (size_t i = 0; i < mRetainedTiles.Length(); i++) {
     if (mRetainedTiles[i].IsPlaceholderTile()) continue;
     mRetainedTiles[i].ReadUnlock();
   }
 }
 void
 ClientTiledLayerBuffer::ReadLock() {
   for (size_t i = 0; i < mRetainedTiles.Length(); i++) {
     if (mRetainedTiles[i].IsPlaceholderTile()) continue;
     mRetainedTiles[i].ReadLock();
   }
 }
 void
 ClientTiledLayerBuffer::Release()
 {
   for (size_t i = 0; i < mRetainedTiles.Length(); i++) {
     if (mRetainedTiles[i].IsPlaceholderTile()) continue;
     mRetainedTiles[i].Release();
   }
 }
 void
 ClientTiledLayerBuffer::DiscardBackBuffers()
 {
   for (size_t i = 0; i < mRetainedTiles.Length(); i++) {
     if (mRetainedTiles[i].IsPlaceholderTile()) continue;
     mRetainedTiles[i].DiscardBackBuffer();
   }
 }
 SurfaceDescriptorTiles
 ClientTiledLayerBuffer::GetSurfaceDescriptorTiles()
 {
   InfallibleTArray<TileDescriptor> tiles;
   for (size_t i = 0; i < mRetainedTiles.Length(); i++) {
     TileDescriptor tileDesc;
     if (mRetainedTiles.SafeElementAt(i, GetPlaceholderTile()) == GetPlaceholderTile()) {
       tileDesc = PlaceholderTileDescriptor();
     } else {
       tileDesc = mRetainedTiles[i].GetTileDescriptor();
     }
     tiles.AppendElement(tileDesc);
   }
   return SurfaceDescriptorTiles(mValidRegion, mPaintedRegion,
                                 tiles, mRetainedWidth, mRetainedHeight,
                                 mResolution, mFrameResolution.scale);
 }
 void
 ClientTiledLayerBuffer::PaintThebes(const nsIntRegion& aNewValidRegion,
                                    const nsIntRegion& aPaintRegion,
                                    LayerManager::DrawThebesLayerCallback aCallback,
                                    void* aCallbackData)
 {
   mCallback = aCallback;
   mCallbackData = aCallbackData;
 #ifdef GFX_TILEDLAYER_PREF_WARNINGS
   long start = PR_IntervalNow();
 #endif
   // If this region is empty XMost() - 1 will give us a negative value.
   NS_ASSERTION(!aPaintRegion.GetBounds().IsEmpty(), "Empty paint region\n");
   bool useSinglePaintBuffer = UseSinglePaintBuffer();
   // XXX The single-tile case doesn't work at the moment, see bug 850396
   /*
   if (useSinglePaintBuffer) {
     // Check if the paint only spans a single tile. If that's
     // the case there's no point in using a single paint buffer.
     nsIntRect paintBounds = aPaintRegion.GetBounds();
     useSinglePaintBuffer = GetTileStart(paintBounds.x) !=
                            GetTileStart(paintBounds.XMost() - 1) ||
                            GetTileStart(paintBounds.y) !=
                            GetTileStart(paintBounds.YMost() - 1);
   }
   */
   if (useSinglePaintBuffer) {
     nsRefPtr<gfxContext> ctxt;
     const nsIntRect bounds = aPaintRegion.GetBounds();
     {
       PROFILER_LABEL("ClientTiledLayerBuffer", "PaintThebesSingleBufferAlloc");
       gfxImageFormat format =
         gfxPlatform::GetPlatform()->OptimalFormatForContent(
           GetContentType());
       mSinglePaintDrawTarget =
         gfxPlatform::GetPlatform()->CreateOffscreenContentDrawTarget(
           gfx::IntSize(ceilf(bounds.width * mResolution),
                        ceilf(bounds.height * mResolution)),
           gfx::ImageFormatToSurfaceFormat(format));
       if (!mSinglePaintDrawTarget) {
         return;
       }
       ctxt = new gfxContext(mSinglePaintDrawTarget);
       mSinglePaintBufferOffset = nsIntPoint(bounds.x, bounds.y);
     }
     ctxt->NewPath();
     ctxt->Scale(mResolution, mResolution);
     ctxt->Translate(gfxPoint(-bounds.x, -bounds.y));
 #ifdef GFX_TILEDLAYER_PREF_WARNINGS
     if (PR_IntervalNow() - start > 3) {
       printf_stderr("Slow alloc %i\n", PR_IntervalNow() - start);
     }
     start = PR_IntervalNow();
 #endif
     PROFILER_LABEL("ClientTiledLayerBuffer", "PaintThebesSingleBufferDraw");
     mCallback(mThebesLayer, ctxt, aPaintRegion, DrawRegionClip::CLIP_NONE, nsIntRegion(), mCallbackData);
   }
 #ifdef GFX_TILEDLAYER_PREF_WARNINGS
   if (PR_IntervalNow() - start > 30) {
     const nsIntRect bounds = aPaintRegion.GetBounds();
     printf_stderr("Time to draw %i: %i, %i, %i, %i\n", PR_IntervalNow() - start, bounds.x, bounds.y, bounds.width, bounds.height);
     if (aPaintRegion.IsComplex()) {
       printf_stderr("Complex region\n");
       nsIntRegionRectIterator it(aPaintRegion);
       for (const nsIntRect* rect = it.Next(); rect != nullptr; rect = it.Next()) {
         printf_stderr(" rect %i, %i, %i, %i\n", rect->x, rect->y, rect->width, rect->height);
       }
     }
   }
   start = PR_IntervalNow();
 #endif
   PROFILER_LABEL("ClientTiledLayerBuffer", "PaintThebesUpdate");
   Update(aNewValidRegion, aPaintRegion);
 #ifdef GFX_TILEDLAYER_PREF_WARNINGS
   if (PR_IntervalNow() - start > 10) {
     const nsIntRect bounds = aPaintRegion.GetBounds();
     printf_stderr("Time to tile %i: %i, %i, %i, %i\n", PR_IntervalNow() - start, bounds.x, bounds.y, bounds.width, bounds.height);
   }
 #endif
   mLastPaintOpaque = mThebesLayer->CanUseOpaqueSurface();
   mCallback = nullptr;
   mCallbackData = nullptr;
   mSinglePaintDrawTarget = nullptr;
 }
 TileClient
 ClientTiledLayerBuffer::ValidateTile(TileClient aTile,
                                     const nsIntPoint& aTileOrigin,
                                     const nsIntRegion& aDirtyRegion)
 {
   PROFILER_LABEL("ClientTiledLayerBuffer", "ValidateTile");
 #ifdef GFX_TILEDLAYER_PREF_WARNINGS
   if (aDirtyRegion.IsComplex()) {
     printf_stderr("Complex region\n");
   }
 #endif
   if (aTile.IsPlaceholderTile()) {
     aTile.SetLayerManager(mManager);
   }
   // Discard our front and backbuffers if our contents changed. In this case
   // the calling code will already have taken care of invalidating the entire
   // layer.
   if (HasFormatChanged()) {
     aTile.DiscardBackBuffer();
     aTile.DiscardFrontBuffer();
   }
   bool createdTextureClient = false;
   nsIntRegion offsetScaledDirtyRegion = aDirtyRegion.MovedBy(-aTileOrigin);
   offsetScaledDirtyRegion.ScaleRoundOut(mResolution, mResolution);
   bool usingSinglePaintBuffer = !!mSinglePaintDrawTarget;
   RefPtr<TextureClient> backBuffer =
     aTile.GetBackBuffer(offsetScaledDirtyRegion,
                         mManager->GetTexturePool(gfxPlatform::GetPlatform()->Optimal2DFormatForContent(GetContentType())),
                         &createdTextureClient, !usingSinglePaintBuffer);
   if (!backBuffer->Lock(OPEN_READ_WRITE)) {
     NS_WARNING("Failed to lock tile TextureClient for updating.");
     aTile.DiscardFrontBuffer();
     return aTile;
   }
   // We must not keep a reference to the DrawTarget after it has been unlocked,
   // make sure these are null'd before unlocking as destruction of the context
   // may cause the target to be flushed.
   RefPtr<DrawTarget> drawTarget = backBuffer->GetAsDrawTarget();
   drawTarget->SetTransform(Matrix());
   RefPtr<gfxContext> ctxt = new gfxContext(drawTarget);
   if (usingSinglePaintBuffer) {
     // XXX Perhaps we should just copy the bounding rectangle here?
     RefPtr<gfx::SourceSurface> source = mSinglePaintDrawTarget->Snapshot();
     nsIntRegionRectIterator it(aDirtyRegion);
     for (const nsIntRect* dirtyRect = it.Next(); dirtyRect != nullptr; dirtyRect = it.Next()) {
 #ifdef GFX_TILEDLAYER_PREF_WARNINGS
       printf_stderr(" break into subdirtyRect %i, %i, %i, %i\n",
                     dirtyRect->x, dirtyRect->y, dirtyRect->width, dirtyRect->height);
 #endif
       gfx::Rect drawRect(dirtyRect->x - aTileOrigin.x,
                          dirtyRect->y - aTileOrigin.y,
                          dirtyRect->width,
                          dirtyRect->height);
       drawRect.Scale(mResolution);
       gfx::IntRect copyRect(NS_roundf((dirtyRect->x - mSinglePaintBufferOffset.x) * mResolution),
                             NS_roundf((dirtyRect->y - mSinglePaintBufferOffset.y) * mResolution),
                             drawRect.width,
                             drawRect.height);
       gfx::IntPoint copyTarget(NS_roundf(drawRect.x), NS_roundf(drawRect.y));
       drawTarget->CopySurface(source, copyRect, copyTarget);
       // Mark the newly updated area as invalid in the front buffer
       aTile.mInvalidFront.Or(aTile.mInvalidFront, nsIntRect(copyTarget.x, copyTarget.y, copyRect.width, copyRect.height));
     }
     // The new buffer is now validated, remove the dirty region from it.
     aTile.mInvalidBack.Sub(nsIntRect(0, 0, GetTileSize().width, GetTileSize().height),
                            offsetScaledDirtyRegion);
   } else {
     // Area of the full tile...
     nsIntRegion tileRegion =
       nsIntRect(aTileOrigin.x, aTileOrigin.y,
                 GetScaledTileSize().width, GetScaledTileSize().height);
     // Intersect this area with the portion that's dirty.
     tileRegion = tileRegion.Intersect(aDirtyRegion);
     // Add the resolution scale to store the dirty region.
     nsIntPoint unscaledTileOrigin = nsIntPoint(aTileOrigin.x * mResolution,
                                                aTileOrigin.y * mResolution);
     nsIntRegion unscaledTileRegion(tileRegion);
     unscaledTileRegion.ScaleRoundOut(mResolution, mResolution);
     // Move invalid areas into scaled layer space.
     aTile.mInvalidFront.MoveBy(unscaledTileOrigin);
     aTile.mInvalidBack.MoveBy(unscaledTileOrigin);
     // Add the area that's going to be redrawn to the invalid area of the
     // front region.
     aTile.mInvalidFront.Or(aTile.mInvalidFront, unscaledTileRegion);
     // Add invalid areas of the backbuffer to the area to redraw.
     tileRegion.Or(tileRegion, aTile.mInvalidBack);
     // Move invalid areas back into tile space.
     aTile.mInvalidFront.MoveBy(-unscaledTileOrigin);
     // This will be validated now.
     aTile.mInvalidBack.SetEmpty();
     nsIntRect bounds = tileRegion.GetBounds();
     bounds.MoveBy(-aTileOrigin);
     if (GetContentType() != gfxContentType::COLOR) {
       drawTarget->ClearRect(Rect(bounds.x, bounds.y, bounds.width, bounds.height));
     }
     ctxt->NewPath();
     ctxt->Clip(gfxRect(bounds.x, bounds.y, bounds.width, bounds.height));
     ctxt->Translate(gfxPoint(-unscaledTileOrigin.x, -unscaledTileOrigin.y));
     ctxt->Scale(mResolution, mResolution);
     mCallback(mThebesLayer, ctxt,
               tileRegion.GetBounds(),
               DrawRegionClip::CLIP_NONE,
               nsIntRegion(), mCallbackData);
   }
 #ifdef GFX_TILEDLAYER_DEBUG_OVERLAY
   DrawDebugOverlay(drawTarget, aTileOrigin.x * mResolution,
                    aTileOrigin.y * mResolution, GetTileLength(), GetTileLength());
 #endif
   ctxt = nullptr;
   drawTarget = nullptr;
   backBuffer->Unlock();
   aTile.Flip();
   if (createdTextureClient) {
     if (!mCompositableClient->AddTextureClient(backBuffer)) {
       NS_WARNING("Failed to add tile TextureClient.");
       aTile.DiscardFrontBuffer();
       aTile.DiscardBackBuffer();
       return aTile;
     }
   }
   // Note, we don't call UpdatedTexture. The Updated function is called manually
   // by the TiledContentHost before composition.
   if (backBuffer->HasInternalBuffer()) {
     // If our new buffer has an internal buffer, we don't want to keep another
     // TextureClient around unnecessarily, so discard the back-buffer.
     aTile.DiscardBackBuffer();
   }
   return aTile;
 }
 static LayoutDeviceRect
 TransformCompositionBounds(const ParentLayerRect& aCompositionBounds,
                            const CSSToParentLayerScale& aZoom,
                            const ParentLayerPoint& aScrollOffset,
                            const CSSToParentLayerScale& aResolution,
                            const gfx3DMatrix& aTransformParentLayerToLayoutDevice)
 {
   // Transform the current composition bounds into ParentLayer coordinates
   // by compensating for the difference in resolution and subtracting the
   // old composition bounds origin.
   ParentLayerRect offsetViewportRect = (aCompositionBounds / aZoom) * aResolution;
   offsetViewportRect.MoveBy(-aScrollOffset);
   gfxRect transformedViewport =
     aTransformParentLayerToLayoutDevice.TransformBounds(
       gfxRect(offsetViewportRect.x, offsetViewportRect.y,
               offsetViewportRect.width, offsetViewportRect.height));
   return LayoutDeviceRect(transformedViewport.x,
                           transformedViewport.y,
                           transformedViewport.width,
                           transformedViewport.height);
 }
 bool
 ClientTiledLayerBuffer::ComputeProgressiveUpdateRegion(const nsIntRegion& aInvalidRegion,
                                                        const nsIntRegion& aOldValidRegion,
                                                        nsIntRegion& aRegionToPaint,
                                                        BasicTiledLayerPaintData* aPaintData,
                                                        bool aIsRepeated)
 {
   aRegionToPaint = aInvalidRegion;
   // If the composition bounds rect is empty, we can't make any sensible
   // decision about how to update coherently. In this case, just update
   // everything in one transaction.
   if (aPaintData->mCompositionBounds.IsEmpty()) {
     aPaintData->mPaintFinished = true;
     return false;
   }
   // If this is a low precision buffer, we force progressive updates. The
   // assumption is that the contents is less important, so visual coherency
   // is lower priority than speed.
   bool drawingLowPrecision = IsLowPrecision();
   // Find out if we have any non-stale content to update.
   nsIntRegion staleRegion;
   staleRegion.And(aInvalidRegion, aOldValidRegion);
   // Find out the current view transform to determine which tiles to draw
   // first, and see if we should just abort this paint. Aborting is usually
   // caused by there being an incoming, more relevant paint.
   ParentLayerRect compositionBounds;
   CSSToParentLayerScale zoom;
 #if defined(MOZ_WIDGET_ANDROID)
   bool abortPaint = mManager->ProgressiveUpdateCallback(!staleRegion.Contains(aInvalidRegion),
                                                         compositionBounds, zoom,
                                                         !drawingLowPrecision);
 #else
   MOZ_ASSERT(mSharedFrameMetricsHelper);
   ContainerLayer* parent = mThebesLayer->AsLayer()->GetParent();
   bool abortPaint =
     mSharedFrameMetricsHelper->UpdateFromCompositorFrameMetrics(
       parent,
       !staleRegion.Contains(aInvalidRegion),
       drawingLowPrecision,
       compositionBounds,
       zoom);
 #endif
   if (abortPaint) {
     // We ignore if front-end wants to abort if this is the first,
     // non-low-precision paint, as in that situation, we're about to override
     // front-end's page/viewport metrics.
     if (!aPaintData->mFirstPaint || drawingLowPrecision) {
       PROFILER_LABEL("ContentClient", "Abort painting");
       aRegionToPaint.SetEmpty();
       return aIsRepeated;
     }
   }
   // Transform the composition bounds, which is in the ParentLayer coordinates
   // of the nearest ContainerLayer with a valid displayport to LayoutDevice
   // coordinates relative to this layer.
   LayoutDeviceRect transformedCompositionBounds =
     TransformCompositionBounds(compositionBounds, zoom, aPaintData->mScrollOffset,
                                aPaintData->mResolution, aPaintData->mTransformParentLayerToLayoutDevice);
   // Paint tiles that have stale content or that intersected with the screen
   // at the time of issuing the draw command in a single transaction first.
   // This is to avoid rendering glitches on animated page content, and when
   // layers change size/shape.
   LayoutDeviceRect typedCoherentUpdateRect =
     transformedCompositionBounds.Intersect(aPaintData->mCompositionBounds);
   // Offset by the viewport origin, as the composition bounds are stored in
   // Layer space and not LayoutDevice space.
   typedCoherentUpdateRect.MoveBy(aPaintData->mViewport.TopLeft());
   // Convert to untyped to intersect with the invalid region.
   nsIntRect roundedCoherentUpdateRect =
     LayoutDeviceIntRect::ToUntyped(RoundedOut(typedCoherentUpdateRect));
   aRegionToPaint.And(aInvalidRegion, roundedCoherentUpdateRect);
   aRegionToPaint.Or(aRegionToPaint, staleRegion);
   bool drawingStale = !aRegionToPaint.IsEmpty();
   if (!drawingStale) {
     aRegionToPaint = aInvalidRegion;
   }
   // Prioritise tiles that are currently visible on the screen.
   bool paintVisible = false;
   if (aRegionToPaint.Intersects(roundedCoherentUpdateRect)) {
     aRegionToPaint.And(aRegionToPaint, roundedCoherentUpdateRect);
     paintVisible = true;
   }
   // Paint area that's visible and overlaps previously valid content to avoid
   // visible glitches in animated elements, such as gifs.
   bool paintInSingleTransaction = paintVisible && (drawingStale || aPaintData->mFirstPaint);
   // The following code decides what order to draw tiles in, based on the
   // current scroll direction of the primary scrollable layer.
   NS_ASSERTION(!aRegionToPaint.IsEmpty(), "Unexpectedly empty paint region!");
   nsIntRect paintBounds = aRegionToPaint.GetBounds();
   int startX, incX, startY, incY;
   gfx::IntSize scaledTileSize = GetScaledTileSize();
   if (aPaintData->mScrollOffset.x >= aPaintData->mLastScrollOffset.x) {
     startX = RoundDownToTileEdge(paintBounds.x, scaledTileSize.width);
     incX = scaledTileSize.width;
   } else {
     startX = RoundDownToTileEdge(paintBounds.XMost() - 1, scaledTileSize.width);
     incX = -scaledTileSize.width;
   }
   if (aPaintData->mScrollOffset.y >= aPaintData->mLastScrollOffset.y) {
     startY = RoundDownToTileEdge(paintBounds.y, scaledTileSize.height);
     incY = scaledTileSize.height;
   } else {
     startY = RoundDownToTileEdge(paintBounds.YMost() - 1, scaledTileSize.height);
     incY = -scaledTileSize.height;
   }
   // Find a tile to draw.
   nsIntRect tileBounds(startX, startY, scaledTileSize.width, scaledTileSize.height);
   int32_t scrollDiffX = aPaintData->mScrollOffset.x - aPaintData->mLastScrollOffset.x;
   int32_t scrollDiffY = aPaintData->mScrollOffset.y - aPaintData->mLastScrollOffset.y;
   // This loop will always terminate, as there is at least one tile area
   // along the first/last row/column intersecting with regionToPaint, or its
   // bounds would have been smaller.
   while (true) {
     aRegionToPaint.And(aInvalidRegion, tileBounds);
     if (!aRegionToPaint.IsEmpty()) {
       break;
     }
     if (Abs(scrollDiffY) >= Abs(scrollDiffX)) {
       tileBounds.x += incX;
     } else {
       tileBounds.y += incY;
     }
   }
   if (!aRegionToPaint.Contains(aInvalidRegion)) {
     // The region needed to paint is larger then our progressive chunk size
     // therefore update what we want to paint and ask for a new paint transaction.
     // If we need to draw more than one tile to maintain coherency, make
     // sure it happens in the same transaction by requesting this work be
     // repeated immediately.
     // If this is unnecessary, the remaining work will be done tile-by-tile in
     // subsequent transactions.
     if (!drawingLowPrecision && paintInSingleTransaction) {
       return true;
     }
     mManager->SetRepeatTransaction();
     return false;
   }
   // We're not repeating painting and we've not requested a repeat transaction,
   // so the paint is finished. If there's still a separate low precision
   // paint to do, it will get marked as unfinished later.
   aPaintData->mPaintFinished = true;
   return false;
 }
 bool
 ClientTiledLayerBuffer::ProgressiveUpdate(nsIntRegion& aValidRegion,
                                          nsIntRegion& aInvalidRegion,
                                          const nsIntRegion& aOldValidRegion,
                                          BasicTiledLayerPaintData* aPaintData,
                                          LayerManager::DrawThebesLayerCallback aCallback,
                                          void* aCallbackData)
 {
   bool repeat = false;
   bool isBufferChanged = false;
   do {
     // Compute the region that should be updated. Repeat as many times as
     // is required.
     nsIntRegion regionToPaint;
     repeat = ComputeProgressiveUpdateRegion(aInvalidRegion,
                                             aOldValidRegion,
                                             regionToPaint,
                                             aPaintData,
                                             repeat);
     // There's no further work to be done.
     if (regionToPaint.IsEmpty()) {
       break;
     }
     isBufferChanged = true;
     // Keep track of what we're about to refresh.
     aValidRegion.Or(aValidRegion, regionToPaint);
     // aValidRegion may have been altered by InvalidateRegion, but we still
     // want to display stale content until it gets progressively updated.
     // Create a region that includes stale content.
     nsIntRegion validOrStale;
     validOrStale.Or(aValidRegion, aOldValidRegion);
     // Paint the computed region and subtract it from the invalid region.
     PaintThebes(validOrStale, regionToPaint, aCallback, aCallbackData);
     aInvalidRegion.Sub(aInvalidRegion, regionToPaint);
   } while (repeat);
   // Return false if nothing has been drawn, or give what has been drawn
   // to the shadow layer to upload.
   return isBufferChanged;
 }
 }
 }

The Tor Browser / annotate

gfx/layers/client/TiledContentClient.cpp@6474c204b198 (annotated)

gfx/layers/client/TiledContentClient.cpp