Input event filtering and compositor thread setup.

content/renderer/gpu/compositor_thread.cc

Index: content/renderer/gpu/compositor_thread.cc
===================================================================
--- content/renderer/gpu/compositor_thread.cc	(revision 0)
+++ content/renderer/gpu/compositor_thread.cc	(revision 0)
@@ -0,0 +1,113 @@
+// Copyright (c) 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 "content/renderer/gpu/compositor_thread.h"
+
+#include "base/bind.h"
+#include "content/renderer/gpu/input_event_filter.h"
+#include "third_party/WebKit/Source/WebKit/chromium/public/WebCompositor.h"
+#include "third_party/WebKit/Source/WebKit/chromium/public/WebCompositorClient.h"
+
+using WebKit::WebCompositor;
+using WebKit::WebInputEvent;
+
+//------------------------------------------------------------------------------
+
+class CompositorThread::CompositorWrapper : public WebKit::WebCompositorClient {
+ public:
+  CompositorWrapper(CompositorThread* compositor_thread,
+                    int routing_id,
+                    WebKit::WebCompositor* compositor)
+      : compositor_thread_(compositor_thread),
+        routing_id_(routing_id),
+        compositor_(compositor) {
+    compositor_->setClient(this);
+  }
+
+  ~CompositorWrapper() {

[jamesr, 2011/10/05 21:34:42]

one more nit: i think this should be marked virtual (it is actually virtual
anyway because the d'tor of WebKit::WebCompositorClient is declared virtual, but
good to be explicit about it)

+    compositor_->setClient(NULL);
+  }
+
+  int routing_id() const { return routing_id_; }
+  WebKit::WebCompositor* compositor() const { return compositor_; }
+
+  // WebCompositorClient methods:
+
+  virtual void willShutdown() {
+    compositor_thread_->RemoveCompositor(routing_id_);
+  }
+
+  virtual void didHandleInputEvent() {
+    compositor_thread_->filter_->DidHandleInputEvent();
+  }
+
+  virtual void didNotHandleInputEvent(bool send_to_widget) {
+    compositor_thread_->filter_->DidNotHandleInputEvent(send_to_widget);
+  }
+
+ private:
+  CompositorThread* compositor_thread_;
+  int routing_id_;
+  WebKit::WebCompositor* compositor_;
+
+  DISALLOW_COPY_AND_ASSIGN(CompositorWrapper);
+};
+
+//------------------------------------------------------------------------------
+
+CompositorThread::CompositorThread(IPC::Channel::Listener* main_listener)
+    : thread_("Compositor") {
+  filter_ =
+      new InputEventFilter(main_listener,
+                           thread_.message_loop()->message_loop_proxy(),
+                           base::Bind(&CompositorThread::HandleInputEvent,
+                                      base::Unretained(this)));
+  WebCompositor::setThread(&thread_);
+}
+
+CompositorThread::~CompositorThread() {
+}
+
+IPC::ChannelProxy::MessageFilter* CompositorThread::GetMessageFilter() const {
+  return filter_;
+}
+
+void CompositorThread::AddCompositor(int routing_id, int compositor_id) {
+  if (thread_.message_loop() != MessageLoop::current()) {
+    thread_.message_loop()->PostTask(
+        FROM_HERE,
+        base::Bind(&CompositorThread::AddCompositor, base::Unretained(this),
+                   routing_id, compositor_id));
+    return;
+  }
+
+  WebCompositor* compositor = WebCompositor::fromIdentifier(compositor_id);
+  if (!compositor)
+    return;
+
+  filter_->AddRoute(routing_id);
+  compositors_[routing_id] =
+      make_linked_ptr(new CompositorWrapper(this, routing_id, compositor));
+}
+
+void CompositorThread::RemoveCompositor(int routing_id) {
+  DCHECK(thread_.message_loop() == MessageLoop::current());
+
+  filter_->RemoveRoute(routing_id);
+  compositors_.erase(routing_id);
+}
+
+void CompositorThread::HandleInputEvent(
+    int routing_id,
+    const WebInputEvent* input_event) {
+  DCHECK_EQ(MessageLoop::current(), thread_.message_loop());
+
+  CompositorMap::iterator it = compositors_.find(routing_id);
+  DCHECK(it != compositors_.end());
+
+  CompositorWrapper* wrapper = it->second.get();
+  DCHECK_EQ(routing_id, wrapper->routing_id());

[jam, 2011/10/05 21:41:49]

nit: do you think this dcheck will ever trip up? are you that worried about
developers messing up two functions above?

+
+  wrapper->compositor()->handleInputEvent(*input_event);
+}