Add CC software renderer.

cc/CCLayerTreeHostImpl.cpp

 // Copyright 2011 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "config.h"
 
 #include "CCLayerTreeHostImpl.h"
 
 #include "CCAppendQuadsData.h"
 #include "CCDamageTracker.h"
 #include "CCDebugRectHistory.h"
 #include "CCDelayBasedTimeSource.h"
 #include "CCFontAtlas.h"
 #include "CCFrameRateCounter.h"
 #include "CCHeadsUpDisplayLayerImpl.h"
 #include "CCLayerIterator.h"
 #include "CCLayerTreeHost.h"
 #include "CCLayerTreeHostCommon.h"
 #include "CCMathUtil.h"
 #include "CCOverdrawMetrics.h"
 #include "CCPageScaleAnimation.h"
 #include "CCPrioritizedTextureManager.h"
 #include "CCRenderPassDrawQuad.h"
 #include "CCRendererGL.h"
+#include "CCRendererSoftware.h"
 #include "CCRenderingStats.h"
 #include "CCScrollbarAnimationController.h"
 #include "CCScrollbarLayerImpl.h"
 #include "CCSettings.h"
 #include "CCSingleThreadProxy.h"
 #include "TraceEvent.h"
 #include <wtf/CurrentTime.h>
 
 using WebKit::WebTransformationMatrix;
 
@@ skipping 637 matching lines @@
     m_renderer->setVisible(visible);
 
     setBackgroundTickingEnabled(!m_visible && m_needsAnimateLayers);
 }
 
 bool CCLayerTreeHostImpl::initializeRenderer(PassOwnPtr<CCGraphicsContext> context, TextureUploaderOption textureUploader)
 {
     if (!context->bindToClient(this))
         return false;
 
-    WebKit::WebGraphicsContext3D* context3d = context->context3D();
-
-    if (!context3d) {
-        // FIXME: Implement this path for software compositing.
-        return false;
-    }
-
     OwnPtr<CCGraphicsContext> contextRef(context);
     OwnPtr<CCResourceProvider> resourceProvider = CCResourceProvider::create(contextRef.get());
-    OwnPtr<CCRendererGL> renderer;
-    if (resourceProvider.get())
-        renderer = CCRendererGL::create(this, resourceProvider.get(), textureUploader);
+
+    OwnPtr<CCRenderer> renderer;
+    if (resourceProvider.get()) {
+        if (contextRef->context3D())
+            renderer = CCRendererGL::create(this, resourceProvider.get(), textureUploader);
+        else if (contextRef->softwareDevice())
+            renderer = CCRendererSoftware::create(this, resourceProvider.get(), contextRef->softwareDevice());

[danakj, 2012/09/19 18:35:14]

Should there be an else { ASSERT_NOT_REACHED(); } here? Or remove the if on the
else and ASSERT(softwareDevice)?

Or it ok to leave this with renderer == NULL? The release() below makes me think
it's not.

[aelias_OOO_until_Jul13, 2012/09/19 19:58:27]

The release() will not crash given a NULL pointer.  This function returns false
if the renderer could not be initialized.

[danakj, 2012/09/19 20:06:18]

ah ok! right it didn't worry about else before either. "else if" without else is
just a warning trigger in my internal compiler :)

+    }
 
     // Since we now have a new context/renderer, we cannot continue to use the old
     // resources (i.e. renderSurfaces and texture IDs).
     if (m_rootLayerImpl) {
         clearRenderSurfaces();
         sendDidLoseContextRecursive(m_rootLayerImpl.get());
     }
 
     m_renderer = renderer.release();
     m_resourceProvider = resourceProvider.release();
@@ skipping 559 matching lines @@
 
     CCScrollbarAnimationController* scrollbarController = layer->scrollbarAnimationController();
     if (scrollbarController && scrollbarController->animate(monotonicTime))
         m_client->setNeedsRedrawOnImplThread();
 
     for (size_t i = 0; i < layer->children().size(); ++i)
         animateScrollbarsRecursive(layer->children()[i].get(), monotonicTime);
 }
 
 } // namespace cc