Refactoring Canvas2DLayerBridge to make it easier to write unit tests

Source/core/platform/graphics/chromium/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 26 matching lines @@
 #include "core/platform/graphics/gpu/SharedGraphicsContext3D.h"
 #include "public/platform/Platform.h"
 #include "public/platform/WebCompositorSupport.h"
 #include "public/platform/WebGraphicsContext3D.h"
 
 using WebKit::WebExternalTextureLayer;
 using WebKit::WebGraphicsContext3D;
 
 namespace WebCore {
 
-static SkSurface* createSurface(GraphicsContext3D* context3D, const IntSize& size)
-{
-    ASSERT(!context3D->webContext()->isContextLost());
-    GrContext* gr = context3D->grContext();
-    if (!gr)
-        return 0;
-    gr->resetContext();
-    SkImage::Info info;
-    info.fWidth = size.width();
-    info.fHeight = size.height();
-    info.fColorType = SkImage::kPMColor_ColorType;
-    info.fAlphaType = SkImage::kPremul_AlphaType;
-    return SkSurface::NewRenderTarget(gr, info);
-}
-
-PassOwnPtr<Canvas2DLayerBridge> Canvas2DLayerBridge::create(PassRefPtr<GraphicsContext3D> context, const IntSize& size, OpacityMode opacityMode)
+PassOwnPtr<Canvas2DLayerBridge> Canvas2DLayerBridge::create(PassOwnPtr<Helper> helper, const IntSize& size, OpacityMode opacityMode)
 {
     TRACE_EVENT_INSTANT0("test_gpu", "Canvas2DLayerBridgeCreation");
-    SkAutoTUnref<SkSurface> surface(createSurface(context.get(), size));
-    if (!surface.get())
-        return PassOwnPtr<Canvas2DLayerBridge>();
-    SkDeferredCanvas* canvas = new SkDeferredCanvas(surface);
-    OwnPtr<Canvas2DLayerBridge> layerBridge = adoptPtr(new Canvas2DLayerBridge(context, canvas, opacityMode));
+    bool success;
+    OwnPtr<Canvas2DLayerBridge> layerBridge = adoptPtr(new Canvas2DLayerBridge(helper, size, opacityMode, &success));
+    if (!success)
+        layerBridge.clear();
     return layerBridge.release();
 }
 
-Canvas2DLayerBridge::Canvas2DLayerBridge(PassRefPtr<GraphicsContext3D> context, SkDeferredCanvas* canvas, OpacityMode opacityMode)
-    : m_canvas(canvas)
-    , m_context(context)
+Canvas2DLayerBridge::Canvas2DLayerBridge(PassOwnPtr<Helper> helper, const IntSize& size, OpacityMode opacityMode, bool* success)
+    : m_helper(helper)
     , m_bytesAllocated(0)
     , m_didRecordDrawCommand(false)
     , m_surfaceIsValid(true)
     , m_framesPending(0)
     , m_rateLimitingEnabled(false)
     , m_next(0)
     , m_prev(0)
     , m_lastImageId(0)
 {
+    ASSERT(success);
+    m_context = m_helper->getContext();
+    SkAutoTUnref<SkSurface> surface(m_helper->createSurface(m_context.get(), size));
+    if (!surface.get()) {
+        *success = false;
+        return;
+    }
+    m_canvas = new SkDeferredCanvas(surface);
+
     ASSERT(m_canvas);
     // Used by browser tests to detect the use of a Canvas2DLayerBridge.
     TRACE_EVENT_INSTANT0("test_gpu", "Canvas2DLayerBridgeCreation");
     m_layer = adoptPtr(WebKit::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_canvas->setNotificationClient(this);
+    *success = true;
 }
 
 Canvas2DLayerBridge::~Canvas2DLayerBridge()
 {
     GraphicsLayer::unregisterContentsLayer(m_layer->layer());
     Canvas2DLayerManager::get().layerToBeDestroyed(this);
     m_canvas->setNotificationClient(0);
     m_mailboxes.clear();
     m_layer->clearTexture();
     m_layer.clear();
@@ skipping 85 matching lines @@
     return m_context->webContext();
 }
 
 bool Canvas2DLayerBridge::isValid()
 {
     ASSERT(m_layer);
     if (m_context->webContext()->isContextLost() || !m_surfaceIsValid) {
         // Attempt to recover.
         m_layer->clearTexture();
         m_mailboxes.clear();
-        RefPtr<GraphicsContext3D> sharedContext = SharedGraphicsContext3D::get();
+        RefPtr<GraphicsContext3D> sharedContext = m_helper->getContext();
         if (!sharedContext || sharedContext->webContext()->isContextLost()) {
             m_surfaceIsValid = false;
         } else {
             m_context = sharedContext;
             IntSize size(m_canvas->getTopDevice()->width(), m_canvas->getTopDevice()->height());
-            SkAutoTUnref<SkSurface> surface(createSurface(m_context.get(), size));
+            SkAutoTUnref<SkSurface> surface(m_helper->createSurface(m_context.get(), size));
             if (surface.get()) {
                 m_canvas->setSurface(surface.get());
                 m_surfaceIsValid = true;
                 // FIXME: draw sad canvas picture into new buffer crbug.com/243842
             } else {
                 // Surface allocation failed. Set m_surfaceIsValid to false to
                 // trigger subsequent retry.
                 m_surfaceIsValid = false;
             }
         }
@@ skipping 26 matching lines @@
             mailboxInfo->m_image.reset(0);
             mailboxInfo->m_status = MailboxAvailable;
         }
     }
     SkAutoTUnref<SkImage> image(m_canvas->newImageSnapshot());
     // Early exit if canvas was not drawn to since last prepareMailbox
     if (image->uniqueID() == m_lastImageId)
         return false;
     m_lastImageId = image->uniqueID();
 
+    GrTexture* texture = image->getTexture();
+    // TODO: Perform texture upload for cases where image is in RAM. Required for crbug.com/265849
+    if (!texture)
+        return false;
+
     mailboxInfo = createMailboxInfo();
     mailboxInfo->m_status = MailboxInUse;
     mailboxInfo->m_image.swap(&image);
     // Because of texture sharing with the compositor, we must invalidate
     // the state cached in skia so that the deferred copy on write
     // in SkSurface_Gpu does not make any false assumptions.
-    mailboxInfo->m_image->getTexture()->invalidateCachedState();
+    texture->invalidateCachedState();
 
-    ASSERT(mailboxInfo->m_mailbox.syncPoint == 0);
+    ASSERT(!mailboxInfo->m_mailbox.syncPoint);
     ASSERT(mailboxInfo->m_image.get());
-    ASSERT(mailboxInfo->m_image->getTexture());
 
-    m_context->bindTexture(GraphicsContext3D::TEXTURE_2D, mailboxInfo->m_image->getTexture()->getTextureHandle());
+    m_context->bindTexture(GraphicsContext3D::TEXTURE_2D, texture->getTextureHandle());
     m_context->texParameteri(GraphicsContext3D::TEXTURE_2D, GraphicsContext3D::TEXTURE_MAG_FILTER, GraphicsContext3D::LINEAR);
     m_context->texParameteri(GraphicsContext3D::TEXTURE_2D, GraphicsContext3D::TEXTURE_MIN_FILTER, GraphicsContext3D::LINEAR);
     m_context->texParameteri(GraphicsContext3D::TEXTURE_2D, GraphicsContext3D::TEXTURE_WRAP_S, GraphicsContext3D::CLAMP_TO_EDGE);
     m_context->texParameteri(GraphicsContext3D::TEXTURE_2D, GraphicsContext3D::TEXTURE_WRAP_T, GraphicsContext3D::CLAMP_TO_EDGE);
     context()->produceTextureCHROMIUM(GraphicsContext3D::TEXTURE_2D, mailboxInfo->m_mailbox.name);
     context()->flush();
     mailboxInfo->m_mailbox.syncPoint = context()->insertSyncPoint();
     m_context->bindTexture(GraphicsContext3D::TEXTURE_2D, 0);
     // Because we are changing the texture binding without going through skia,
     // we must dirty the context.
     m_context->grContext()->resetContext(kTextureBinding_GrGLBackendState);
-
     *outMailbox = mailboxInfo->m_mailbox;
     return true;
 }
 
 Canvas2DLayerBridge::MailboxInfo* Canvas2DLayerBridge::createMailboxInfo() {
     MailboxInfo* mailboxInfo;
     for (mailboxInfo = m_mailboxes.begin(); mailboxInfo < m_mailboxes.end(); mailboxInfo++) {
         if (mailboxInfo->m_status == MailboxAvailable) {
             return mailboxInfo;
         }
@@ skipping 56 matching lines @@
 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;
 }
 
 }