Improve plugin performance on the Mac

This makes a few changes:
- Switch to memcpy instead of CG drawing to copy pixels from the transport bitmap to the backing bitmap (this is a substantial perf win).
- Send transparancy information to the WebPluginDelegate, since it's no longer equivalent to not having a background DIB on the Mac (and likely on the other platforms in the future).
- Don't clear the transport DIB for non-transparent plugins, since they will be drawing over whatever is there anyway.

BUG=41340
TEST=Both transparent and non-transparent plugins should continue to draw correctly. Framerates for large CG plugins (e.g., in-window Netflix streaming) should be higher.

Review URL: http://codereview.chromium.org/1629017

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@44490 0039d316-1c4b-4281-b951-d872f2087c98

3 files changed, 10 insertions, 4 deletions

diff --git a/chrome/plugin/webplugin_delegate_stub.cc b/chrome/plugin/webplugin_delegate_stub.cc
index dd3f6a0..104c8b9 100644
--- a/chrome/plugin/webplugin_delegate_stub.cc
+++ b/chrome/plugin/webplugin_delegate_stub.cc
@@ -313,7 +313,8 @@ void WebPluginDelegateStub::OnUpdateGeometry(
     const PluginMsg_UpdateGeometry_Param& param) {
   webplugin_->UpdateGeometry(
       param.window_rect, param.clip_rect,
-      param.windowless_buffer, param.background_buffer
+      param.windowless_buffer, param.background_buffer,
+      param.transparent
 #if defined(OS_MACOSX)
       ,
       param.ack_key
diff --git a/chrome/plugin/webplugin_proxy.cc b/chrome/plugin/webplugin_proxy.cc
index ac04589..2dfc7a2 100644
--- a/chrome/plugin/webplugin_proxy.cc
+++ b/chrome/plugin/webplugin_proxy.cc
@@ -55,6 +55,7 @@ WebPluginProxy::WebPluginProxy(
       waiting_for_paint_(false),
       containing_window_(containing_window),
       page_url_(page_url),
+      transparent_(false),
       host_render_view_routing_id_(host_render_view_routing_id),
       ALLOW_THIS_IN_INITIALIZER_LIST(runnable_method_factory_(this)) {
 }
@@ -375,7 +376,7 @@ void WebPluginProxy::Paint(const gfx::Rect& rect) {
     scoped_cftyperef<CGImageRef> sub_image(
         CGImageCreateWithImageInRect(image, source_rect));
     CGContextDrawImage(windowless_context_, rect.ToCGRect(), sub_image);
-  } else {
+  } else if (transparent_) {
     CGContextClearRect(windowless_context_, rect.ToCGRect());
   }
   CGContextClipToRect(windowless_context_, rect.ToCGRect());
@@ -427,7 +428,8 @@ void WebPluginProxy::UpdateGeometry(
     const gfx::Rect& window_rect,
     const gfx::Rect& clip_rect,
     const TransportDIB::Handle& windowless_buffer,
-    const TransportDIB::Handle& background_buffer
+    const TransportDIB::Handle& background_buffer,
+    bool transparent
 #if defined(OS_MACOSX)
     ,
     int ack_key
@@ -435,6 +437,7 @@ void WebPluginProxy::UpdateGeometry(
     ) {
   gfx::Rect old = delegate_->GetRect();
   gfx::Rect old_clip_rect = delegate_->GetClipRect();
+  transparent_ = transparent;
 
   // Update the buffers before doing anything that could call into plugin code,
   // so that we don't process buffer changes out of order if plugins make
diff --git a/chrome/plugin/webplugin_proxy.h b/chrome/plugin/webplugin_proxy.h
index 11cb552..f03de96 100644
--- a/chrome/plugin/webplugin_proxy.h
+++ b/chrome/plugin/webplugin_proxy.h
@@ -117,7 +117,8 @@ class WebPluginProxy : public webkit_glue::WebPlugin {
   void UpdateGeometry(const gfx::Rect& window_rect,
                       const gfx::Rect& clip_rect,
                       const TransportDIB::Handle& windowless_buffer,
-                      const TransportDIB::Handle& background_buffer
+                      const TransportDIB::Handle& background_buffer,
+                      bool transparent
 #if defined(OS_MACOSX)
                       ,
                       int ack_key
@@ -170,6 +171,7 @@ class WebPluginProxy : public webkit_glue::WebPlugin {
 
   // Variables used for desynchronized windowless plugin painting.  See note in
   // webplugin_delegate_proxy.h for how this works.
+  bool transparent_;
 #if defined(OS_MACOSX)
   scoped_ptr<TransportDIB> windowless_dib_;
   scoped_ptr<TransportDIB> background_dib_;