Implement image-rendering:pixelated for accelerated 2D canvases.

Source/platform/graphics/Canvas2DLayerBridge.cpp

 /*
  * Copyright (C) 2012 Google 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
@@ skipping 68 matching lines @@
     , m_contextProvider(contextProvider)
     , m_imageBuffer(0)
     , m_msaaSampleCount(msaaSampleCount)
     , m_bytesAllocated(0)
     , m_didRecordDrawCommand(false)
     , m_isSurfaceValid(true)
     , m_framesPending(0)
     , m_framesSinceMailboxRelease(0)
     , m_destructionInProgress(false)
     , m_rateLimitingEnabled(false)
+    , m_nearestNeighbor(false)
     , m_isHidden(false)
     , m_next(0)
     , m_prev(0)
     , m_lastImageId(0)
     , m_releasedMailboxInfoIndex(InvalidMailboxIndex)
 {
     ASSERT(m_canvas);
     ASSERT(m_surface);
     ASSERT(m_contextProvider);
     // Used by browser tests to detect the use of a Canvas2DLayerBridge.
     TRACE_EVENT_INSTANT0("test_gpu", "Canvas2DLayerBridgeCreation");
     m_layer = adoptPtr(Platform::current()->compositorSupport()->createExternalTextureLayer(this));
     m_layer->setOpaque(opacityMode == Opaque);
     m_layer->setBlendBackgroundColor(opacityMode != Opaque);
     GraphicsLayer::registerContentsLayer(m_layer->layer());
     m_layer->setRateLimitContext(m_rateLimitingEnabled);
+    m_layer->setNearestNeighbor(m_nearestNeighbor);
     m_canvas->setNotificationClient(this);
 #ifndef NDEBUG
     canvas2DLayerBridgeInstanceCounter.increment();
 #endif
 }
 
 Canvas2DLayerBridge::~Canvas2DLayerBridge()
 {
     ASSERT(m_destructionInProgress);
     ASSERT(!Canvas2DLayerManager::get().isInList(this));
@@ skipping 28 matching lines @@
     m_layer->clearTexture();
     // Orphaning the layer is required to trigger the recration of a new layer
     // in the case where destruction is caused by a canvas resize. Test:
     // virtual/gpu/fast/canvas/canvas-resize-after-paint-without-layout.html
     m_layer->layer()->removeFromParent();
     // To anyone who ever hits this assert: Please update crbug.com/344666
     // with repro steps.
     ASSERT(!m_bytesAllocated);
 }
 
+void Canvas2DLayerBridge::setNearestNeighbor(bool nearestNeighbor)
+{
+    ASSERT(!m_destructionInProgress);
+    if (m_nearestNeighbor != nearestNeighbor) {
+        m_nearestNeighbor = nearestNeighbor;
+        m_layer->setNearestNeighbor(m_nearestNeighbor);
+    }
+}
+
 void Canvas2DLayerBridge::setIsHidden(bool hidden)
 {
     ASSERT(!m_destructionInProgress);
     bool newHiddenValue = hidden || m_destructionInProgress;
     if (m_isHidden == newHiddenValue)
         return;
 
     m_isHidden = newHiddenValue;
     if (isHidden()) {
         freeTransientResources();
@@ skipping 424 matching lines @@
     // This copy constructor should only be used for Vector reallocation
     // Assuming 'other' is to be destroyed, we transfer m_image and
     // m_parentLayerBridge ownership rather than do a refcount dance.
     memcpy(&m_mailbox, &other.m_mailbox, sizeof(m_mailbox));
     m_image = const_cast<MailboxInfo*>(&other)->m_image.release();
     m_parentLayerBridge = const_cast<MailboxInfo*>(&other)->m_parentLayerBridge.release();
     m_status = other.m_status;
 }
 
 } // namespace blink