Refactoring ImageBuffer to decouple it from Canvas2DLayerBridge

Source/core/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 25 matching lines @@
 #include "platform/TraceEvent.h"
 #include "public/platform/Platform.h"
 #include "public/platform/WebCompositorSupport.h"
 #include "public/platform/WebGraphicsContext3D.h"
 
 using blink::WebExternalTextureLayer;
 using blink::WebGraphicsContext3D;
 
 namespace WebCore {
 
-void Canvas2DLayerBridgePtr::clear()
-{
-    if (m_ptr) {
-        m_ptr->destroy();
-        m_ptr.clear();
-    }
-}
-
-Canvas2DLayerBridgePtr& Canvas2DLayerBridgePtr::operator=(const PassRefPtr<Canvas2DLayerBridge>& other)
-{
-    clear();
-    m_ptr = other;
-    return *this;
-}
-
 static SkSurface* createSurface(GraphicsContext3D* context3D, const IntSize& size, int msaaSampleCount)
 {
     ASSERT(!context3D->webContext()->isContextLost());
     GrContext* gr = context3D->grContext();
     if (!gr)
         return 0;
     gr->resetContext();
     SkImageInfo info;
     info.fWidth = size.width();
     info.fHeight = size.height();
     info.fColorType = kPMColor_SkColorType;
     info.fAlphaType = kPremul_SkAlphaType;
     return SkSurface::NewRenderTarget(gr, info,  msaaSampleCount);
 }
 
-PassRefPtr<Canvas2DLayerBridge> Canvas2DLayerBridge::create(PassRefPtr<GraphicsContext3D> context, const IntSize& size, OpacityMode opacityMode, int msaaSampleCount)
+PassRefPtr<Canvas2DLayerBridge> Canvas2DLayerBridge::create(const IntSize& size, OpacityMode opacityMode, int msaaSampleCount)
 {
     TRACE_EVENT_INSTANT0("test_gpu", "Canvas2DLayerBridgeCreation");
-    SkAutoTUnref<SkSurface> surface(createSurface(context.get(), size, msaaSampleCount));
-    if (!surface.get()) {
-        return PassRefPtr<Canvas2DLayerBridge>();
+    RefPtr<GraphicsContext3D> context = SharedGraphicsContext3D::get();
+    RefPtr<SkSurface> surface(createSurface(context.get(), size, msaaSampleCount));

[Stephen White, 2013/12/04 21:18:40]

Maybe createSurface() should be renamed createSkSurface(), now that we have
ImageBufferSurface to confuse it with.

+    RefPtr<Canvas2DLayerBridge> layerBridge;
+    if (surface) {
+        OwnPtr<SkDeferredCanvas> canvas = adoptPtr(SkDeferredCanvas::Create(surface.get()));
+        layerBridge = adoptRef(new Canvas2DLayerBridge(context, canvas.release(), msaaSampleCount, opacityMode));
     }
-    RefPtr<SkDeferredCanvas> canvas = adoptRef(SkDeferredCanvas::Create(surface.get()));
-    RefPtr<Canvas2DLayerBridge> layerBridge = adoptRef(new Canvas2DLayerBridge(context, canvas.release(), msaaSampleCount, opacityMode));
     return layerBridge.release();
 }
 
-Canvas2DLayerBridge::Canvas2DLayerBridge(PassRefPtr<GraphicsContext3D> context, PassRefPtr<SkDeferredCanvas> canvas, int msaaSampleCount, OpacityMode opacityMode)
+Canvas2DLayerBridge::Canvas2DLayerBridge(PassRefPtr<GraphicsContext3D> context, PassOwnPtr<SkDeferredCanvas> canvas, int msaaSampleCount, OpacityMode opacityMode)
     : m_canvas(canvas)
     , m_context(context)
     , m_msaaSampleCount(msaaSampleCount)
     , m_bytesAllocated(0)
     , m_didRecordDrawCommand(false)
     , m_surfaceIsValid(true)
     , m_framesPending(0)
     , m_destructionInProgress(false)
     , m_rateLimitingEnabled(false)
     , m_next(0)
@@ skipping 279 matching lines @@
             // Trigger Canvas2DLayerBridge self-destruction if this is the
             // last live mailbox and the layer bridge is not externally
             // referenced.
             ASSERT(mailboxInfo->m_parentLayerBridge.get() == this);
             mailboxInfo->m_parentLayerBridge.clear();
             return;
         }
     }
 }
 
-blink::WebLayer* Canvas2DLayerBridge::layer()
+blink::WebLayer* Canvas2DLayerBridge::layer() const
 {
     ASSERT(m_layer);
     return m_layer->layer();
 }
 
-void Canvas2DLayerBridge::contextAcquired()
+void Canvas2DLayerBridge::aboutToUse()
 {
     ASSERT(!m_destructionInProgress);
     Canvas2DLayerManager::get().layerDidDraw(this);
     m_didRecordDrawCommand = true;
 }
 
-unsigned Canvas2DLayerBridge::backBufferTexture()
+Platform3DObject Canvas2DLayerBridge::getBackingTexture()
 {
     ASSERT(!m_destructionInProgress);
     if (!isValid())
         return 0;
-    contextAcquired();
+    aboutToUse();
     m_canvas->flush();
     m_context->flush();
-    GrRenderTarget* renderTarget = reinterpret_cast<GrRenderTarget*>(m_canvas->getDevice()->accessRenderTarget());
+    GrRenderTarget* renderTarget = m_canvas->getTopDevice()->accessRenderTarget();
     if (renderTarget) {
         return renderTarget->asTexture()->getTextureHandle();
     }
     return 0;
 }
 
 Canvas2DLayerBridge::MailboxInfo::MailboxInfo(const MailboxInfo& other) {
     // This copy constructor should only be used for Vector reallocation
     // Assuming 'other' is to be destroyed, we swap m_image ownership
     // rather than do a refcount dance.
     memcpy(&m_mailbox, &other.m_mailbox, sizeof(m_mailbox));
     m_image.swap(const_cast<SkAutoTUnref<SkImage>*>(&other.m_image));
     m_status = other.m_status;
 }
 
 }